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* [PATCH v4 28/46] KVM: PPC: Book3S HV P9: Reduce irq_work vs guest decrementer races
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

irq_work's use of the DEC SPR is racy with guest<->host switch and guest
entry which flips the DEC interrupt to guest, which could lose a host
work interrupt.

This patch closes one race, and attempts to comment another class of
races.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 1f38a0abc611..989a1ff5ad11 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3745,6 +3745,18 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	if (!(vcpu->arch.ctrl & 1))
 		mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
 
+	/*
+	 * When setting DEC, we must always deal with irq_work_raise via NMI vs
+	 * setting DEC. The problem occurs right as we switch into guest mode
+	 * if a NMI hits and sets pending work and sets DEC, then that will
+	 * apply to the guest and not bring us back to the host.
+	 *
+	 * irq_work_raise could check a flag (or possibly LPCR[HDICE] for
+	 * example) and set HDEC to 1? That wouldn't solve the nested hv
+	 * case which needs to abort the hcall or zero the time limit.
+	 *
+	 * XXX: Another day's problem.
+	 */
 	mtspr(SPRN_DEC, vcpu->arch.dec_expires - tb);
 
 	if (kvmhv_on_pseries()) {
@@ -3879,7 +3891,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	vc->entry_exit_map = 0x101;
 	vc->in_guest = 0;
 
-	mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - tb);
+	set_dec_or_work(local_paca->kvm_hstate.dec_expires - tb);
+
 	mtspr(SPRN_SPRG_VDSO_WRITE, local_paca->sprg_vdso);
 
 	kvmhv_load_host_pmu();
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 29/46] KVM: PPC: Book3S HV P9: Implement the rest of the P9 path in C
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Almost all logic is moved to C, by introducing a new in_guest mode that
selects and branches very early in the interrupt handler to the P9 exit
code.

The remaining assembly is only about 160 lines of low level stack setup,
with VCPU vs host register save and restore, plus a small shim to the
legacy paths in the interrupt handler.

There are two motivations for this, the first is just make the code more
maintainable being in C. The second is to reduce the amount of code
running in a special KVM mode, "realmode". I put that in quotes because
with radix it is no longer necessarily real-mode in the MMU, but it
still has to be treated specially because it may be in real-mode, and
has various important registers like PID, DEC, TB, etc set to guest.
This is hostile to the rest of Linux and can't use arbitrary kernel
functionality or be instrumented well.

This initial patch is a reasonably faithful conversion of the asm code.
It does lack any loop to return quickly back into the guest without
switching out of realmode in the case of unimportant or easily handled
interrupts, as explained in the previous change, handling HV interrupts
in real mode is not so important for P9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/include/asm/asm-prototypes.h |   3 +-
 arch/powerpc/include/asm/kvm_asm.h        |   3 +-
 arch/powerpc/include/asm/kvm_book3s_64.h  |   8 +
 arch/powerpc/kernel/security.c            |   5 +-
 arch/powerpc/kvm/Makefile                 |   3 +
 arch/powerpc/kvm/book3s_64_entry.S        | 246 ++++++++++++++++++++++
 arch/powerpc/kvm/book3s_hv.c              |   9 +-
 arch/powerpc/kvm/book3s_hv_interrupt.c    | 223 ++++++++++++++++++++
 arch/powerpc/kvm/book3s_hv_rmhandlers.S   | 123 +----------
 9 files changed, 500 insertions(+), 123 deletions(-)
 create mode 100644 arch/powerpc/kvm/book3s_hv_interrupt.c

diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index 939f3c94c8f3..7c74c80ed994 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -122,6 +122,7 @@ extern s32 patch__call_flush_branch_caches3;
 extern s32 patch__flush_count_cache_return;
 extern s32 patch__flush_link_stack_return;
 extern s32 patch__call_kvm_flush_link_stack;
+extern s32 patch__call_kvm_flush_link_stack_p9;
 extern s32 patch__memset_nocache, patch__memcpy_nocache;
 
 extern long flush_branch_caches;
@@ -142,7 +143,7 @@ void kvmhv_load_host_pmu(void);
 void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use);
 void kvmhv_load_guest_pmu(struct kvm_vcpu *vcpu);
 
-int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu);
+void kvmppc_p9_enter_guest(struct kvm_vcpu *vcpu);
 
 long kvmppc_h_set_dabr(struct kvm_vcpu *vcpu, unsigned long dabr);
 long kvmppc_h_set_xdabr(struct kvm_vcpu *vcpu, unsigned long dabr,
diff --git a/arch/powerpc/include/asm/kvm_asm.h b/arch/powerpc/include/asm/kvm_asm.h
index a3633560493b..b4f9996bd331 100644
--- a/arch/powerpc/include/asm/kvm_asm.h
+++ b/arch/powerpc/include/asm/kvm_asm.h
@@ -146,7 +146,8 @@
 #define KVM_GUEST_MODE_GUEST	1
 #define KVM_GUEST_MODE_SKIP	2
 #define KVM_GUEST_MODE_GUEST_HV	3
-#define KVM_GUEST_MODE_HOST_HV	4
+#define KVM_GUEST_MODE_GUEST_HV_FAST	4 /* ISA v3.0 with host radix mode */
+#define KVM_GUEST_MODE_HOST_HV	5
 
 #define KVM_INST_FETCH_FAILED	-1
 
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index 9bb9bb370b53..c214bcffb441 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -153,9 +153,17 @@ static inline bool kvmhv_vcpu_is_radix(struct kvm_vcpu *vcpu)
 	return radix;
 }
 
+int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu);
+
 #define KVM_DEFAULT_HPT_ORDER	24	/* 16MB HPT by default */
 #endif
 
+/*
+ * Invalid HDSISR value which is used to indicate when HW has not set the reg.
+ * Used to work around an errata.
+ */
+#define HDSISR_CANARY	0x7fff
+
 /*
  * We use a lock bit in HPTE dword 0 to synchronize updates and
  * accesses to each HPTE, and another bit to indicate non-present
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index e4e1a94ccf6a..3a607c11f20f 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -430,16 +430,19 @@ device_initcall(stf_barrier_debugfs_init);
 
 static void update_branch_cache_flush(void)
 {
-	u32 *site;
+	u32 *site, __maybe_unused *site2;
 
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 	site = &patch__call_kvm_flush_link_stack;
+	site2 = &patch__call_kvm_flush_link_stack_p9;
 	// This controls the branch from guest_exit_cont to kvm_flush_link_stack
 	if (link_stack_flush_type == BRANCH_CACHE_FLUSH_NONE) {
 		patch_instruction_site(site, ppc_inst(PPC_INST_NOP));
+		patch_instruction_site(site2, ppc_inst(PPC_INST_NOP));
 	} else {
 		// Could use HW flush, but that could also flush count cache
 		patch_branch_site(site, (u64)&kvm_flush_link_stack, BRANCH_SET_LINK);
+		patch_branch_site(site2, (u64)&kvm_flush_link_stack, BRANCH_SET_LINK);
 	}
 #endif
 
diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile
index cdd119028f64..40a55a5ba4ff 100644
--- a/arch/powerpc/kvm/Makefile
+++ b/arch/powerpc/kvm/Makefile
@@ -43,6 +43,9 @@ kvm-objs-$(CONFIG_KVM_E500MC) := $(kvm-e500mc-objs)
 kvm-book3s_64-builtin-objs-$(CONFIG_SPAPR_TCE_IOMMU) := \
 	book3s_64_vio_hv.o
 
+kvm-book3s_64-builtin-objs-y += \
+	book3s_hv_interrupt.o
+
 kvm-pr-y := \
 	fpu.o \
 	emulate.o \
diff --git a/arch/powerpc/kvm/book3s_64_entry.S b/arch/powerpc/kvm/book3s_64_entry.S
index de81ab69555b..845df5fefdbd 100644
--- a/arch/powerpc/kvm/book3s_64_entry.S
+++ b/arch/powerpc/kvm/book3s_64_entry.S
@@ -1,11 +1,16 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 #include <asm/asm-offsets.h>
 #include <asm/cache.h>
+#include <asm/code-patching-asm.h>
 #include <asm/exception-64s.h>
+#include <asm/export.h>
 #include <asm/kvm_asm.h>
 #include <asm/kvm_book3s_asm.h>
+#include <asm/mmu.h>
 #include <asm/ppc_asm.h>
+#include <asm/ptrace.h>
 #include <asm/reg.h>
+#include <asm/ultravisor-api.h>
 
 /*
  * These are branched to from interrupt handlers in exception-64s.S which set
@@ -22,10 +27,15 @@
 .global	kvmppc_hcall
 .balign IFETCH_ALIGN_BYTES
 kvmppc_hcall:
+	lbz	r10,HSTATE_IN_GUEST(r13)
+	cmpwi	r10,KVM_GUEST_MODE_GUEST_HV_FAST
+	beq	kvmppc_p9_exit_hcall
 	ld	r10,PACA_EXGEN+EX_R13(r13)
 	SET_SCRATCH0(r10)
 	li	r10,0xc00
 	/* Now we look like kvmppc_interrupt */
+	li	r11,PACA_EXGEN
+	b	1f
 
 /*
  * KVM interrupt entry occurs after GEN_INT_ENTRY runs, and follows that
@@ -46,6 +56,12 @@ kvmppc_hcall:
 .global	kvmppc_interrupt
 .balign IFETCH_ALIGN_BYTES
 kvmppc_interrupt:
+	std	r10,HSTATE_SCRATCH0(r13)
+	lbz	r10,HSTATE_IN_GUEST(r13)
+	cmpwi	r10,KVM_GUEST_MODE_GUEST_HV_FAST
+	beq	kvmppc_p9_exit_interrupt
+	ld	r10,HSTATE_SCRATCH0(r13)
+	lbz	r11,HSTATE_IN_GUEST(r13)
 	li	r11,PACA_EXGEN
 	cmpdi	r10,0x200
 	bgt+	1f
@@ -140,3 +156,233 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	GET_SCRATCH0(r13)
 	HRFI_TO_KERNEL
 #endif
+
+/* Stack frame offsets for kvmppc_hv_entry */
+#define SFS			(144 + STACK_FRAME_MIN_SIZE)
+#define STACK_SLOT_NVGPRS	(SFS - 144)	/* 18 gprs */
+
+/*
+ * void kvmppc_p9_enter_guest(struct vcpu *vcpu);
+ *
+ * Enter the guest on a ISAv3.0 or later system where we have exactly
+ * one vcpu per vcore, and both the host and guest are radix, and threads
+ * are set to "indepdent mode".
+ */
+.balign	IFETCH_ALIGN_BYTES
+_GLOBAL(kvmppc_p9_enter_guest)
+EXPORT_SYMBOL_GPL(kvmppc_p9_enter_guest)
+	mflr	r0
+	std	r0,PPC_LR_STKOFF(r1)
+	stdu	r1,-SFS(r1)
+
+	std	r1,HSTATE_HOST_R1(r13)
+
+	mfcr	r4
+	stw	r4,SFS+8(r1)
+
+	reg = 14
+	.rept	18
+	std	reg,STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1)
+	reg = reg + 1
+	.endr
+
+	ld	r4,VCPU_LR(r3)
+	mtlr	r4
+	ld	r4,VCPU_CTR(r3)
+	mtctr	r4
+	ld	r4,VCPU_XER(r3)
+	mtspr	SPRN_XER,r4
+
+	ld	r1,VCPU_CR(r3)
+
+BEGIN_FTR_SECTION
+	ld	r4,VCPU_CFAR(r3)
+	mtspr	SPRN_CFAR,r4
+END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
+BEGIN_FTR_SECTION
+	ld	r4,VCPU_PPR(r3)
+	mtspr	SPRN_PPR,r4
+END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
+
+	reg = 4
+	.rept	28
+	ld	reg,__VCPU_GPR(reg)(r3)
+	reg = reg + 1
+	.endr
+
+	ld	r4,VCPU_KVM(r3)
+	lbz	r4,KVM_SECURE_GUEST(r4)
+	cmpdi	r4,0
+	ld	r4,VCPU_GPR(R4)(r3)
+	bne	.Lret_to_ultra
+
+	mtcr	r1
+
+	ld	r0,VCPU_GPR(R0)(r3)
+	ld	r1,VCPU_GPR(R1)(r3)
+	ld	r2,VCPU_GPR(R2)(r3)
+	ld	r3,VCPU_GPR(R3)(r3)
+
+	HRFI_TO_GUEST
+	b	.
+
+	/*
+	 * Use UV_RETURN ultracall to return control back to the Ultravisor
+	 * after processing an hypercall or interrupt that was forwarded
+	 * (a.k.a. reflected) to the Hypervisor.
+	 *
+	 * All registers have already been reloaded except the ucall requires:
+	 *   R0 = hcall result
+	 *   R2 = SRR1, so UV can detect a synthesized interrupt (if any)
+	 *   R3 = UV_RETURN
+	 */
+.Lret_to_ultra:
+	mtcr	r1
+	ld	r1,VCPU_GPR(R1)(r3)
+
+	ld	r0,VCPU_GPR(R3)(r3)
+	mfspr	r2,SPRN_SRR1
+	LOAD_REG_IMMEDIATE(r3, UV_RETURN)
+	sc	2
+
+/*
+ * kvmppc_p9_exit_hcall and kvmppc_p9_exit_interrupt are branched to from
+ * above if the interrupt was taken for a guest that was entered via
+ * kvmppc_p9_enter_guest().
+ *
+ * This code recovers the host stack and vcpu pointer, saves all GPRs and
+ * CR, LR, CTR, XER as well as guest MSR and NIA into the VCPU, then re-
+ * establishes the host stack and registers to return from  the
+ * kvmppc_p9_enter_guest() function.
+ */
+.balign	IFETCH_ALIGN_BYTES
+kvmppc_p9_exit_hcall:
+	mfspr	r11,SPRN_SRR0
+	mfspr	r12,SPRN_SRR1
+	li	r10,0xc00
+	std	r10,HSTATE_SCRATCH0(r13)
+
+.balign	IFETCH_ALIGN_BYTES
+kvmppc_p9_exit_interrupt:
+	/*
+	 * If set to KVM_GUEST_MODE_GUEST_HV_FAST but we're still in the
+	 * hypervisor, that means we can't return from the entry stack.
+	 */
+	rldicl. r10,r12,64-MSR_HV_LG,63
+	bne-	kvmppc_p9_bad_interrupt
+
+	std     r1,HSTATE_SCRATCH1(r13)
+	std     r3,HSTATE_SCRATCH2(r13)
+	ld	r1,HSTATE_HOST_R1(r13)
+	ld	r3,HSTATE_KVM_VCPU(r13)
+
+	std	r9,VCPU_CR(r3)
+
+1:
+	std	r11,VCPU_PC(r3)
+	std	r12,VCPU_MSR(r3)
+
+	reg = 14
+	.rept	18
+	std	reg,__VCPU_GPR(reg)(r3)
+	reg = reg + 1
+	.endr
+
+	/* r1, r3, r9-r13 are saved to vcpu by C code */
+	std	r0,VCPU_GPR(R0)(r3)
+	std	r2,VCPU_GPR(R2)(r3)
+	reg = 4
+	.rept	5
+	std	reg,__VCPU_GPR(reg)(r3)
+	reg = reg + 1
+	.endr
+
+	ld	r2,PACATOC(r13)
+
+	mflr	r4
+	std	r4,VCPU_LR(r3)
+	mfspr	r4,SPRN_XER
+	std	r4,VCPU_XER(r3)
+
+	reg = 14
+	.rept	18
+	ld	reg,STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1)
+	reg = reg + 1
+	.endr
+
+	lwz	r4,SFS+8(r1)
+	mtcr	r4
+
+	/*
+	 * Flush the link stack here, before executing the first blr on the
+	 * way out of the guest.
+	 *
+	 * The link stack won't match coming out of the guest anyway so the
+	 * only cost is the flush itself. The call clobbers r0.
+	 */
+1:	nop
+	patch_site 1b patch__call_kvm_flush_link_stack_p9
+
+	addi	r1,r1,SFS
+	ld	r0,PPC_LR_STKOFF(r1)
+	mtlr	r0
+	blr
+
+/*
+ * Took an interrupt somewhere right before HRFID to guest, so registers are
+ * in a bad way. Return things hopefully enough to run host virtual code and
+ * run the Linux interrupt handler (SRESET or MCE) to print something useful.
+ *
+ * We could be really clever and save all host registers in known locations
+ * before setting HSTATE_IN_GUEST, then restoring them all here, and setting
+ * return address to a fixup that sets them up again. But that's a lot of
+ * effort for a small bit of code. Lots of other things to do first.
+ */
+kvmppc_p9_bad_interrupt:
+	/*
+	 * Set GUEST_MODE_NONE so the handler won't branch to KVM, and clear
+	 * MSR_RI in r12 ([H]SRR1) so the handler won't try to return.
+	 */
+	li	r10,KVM_GUEST_MODE_NONE
+	stb	r10,HSTATE_IN_GUEST(r13)
+	li	r10,MSR_RI
+	andc	r12,r12,r10
+
+	/*
+	 * Clean up guest registers to give host a chance to run.
+	 */
+	li	r10,0
+	mtspr	SPRN_AMR,r10
+	mtspr	SPRN_IAMR,r10
+	mtspr	SPRN_CIABR,r10
+	mtspr	SPRN_DAWRX0,r10
+BEGIN_FTR_SECTION
+	mtspr	SPRN_DAWRX1,r10
+END_FTR_SECTION_IFSET(CPU_FTR_DAWR1)
+	mtspr	SPRN_PID,r10
+
+	/*
+	 * Switch to host MMU mode
+	 */
+	ld	r10, HSTATE_KVM_VCPU(r13)
+	ld	r10, VCPU_KVM(r10)
+	lwz	r10, KVM_HOST_LPID(r10)
+	mtspr	SPRN_LPID,r10
+
+	ld	r10, HSTATE_KVM_VCPU(r13)
+	ld	r10, VCPU_KVM(r10)
+	ld	r10, KVM_HOST_LPCR(r10)
+	mtspr	SPRN_LPCR,r10
+
+	/*
+	 * Go back to interrupt handler
+	 */
+	ld	r10,HSTATE_SCRATCH0(r13)
+	cmpwi	r10,BOOK3S_INTERRUPT_MACHINE_CHECK
+	beq	machine_check_common
+
+	ld	r10,HSTATE_SCRATCH0(r13)
+	cmpwi	r10,BOOK3S_INTERRUPT_SYSTEM_RESET
+	beq	system_reset_common
+
+	b	.
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 989a1ff5ad11..6dca639ed997 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1431,6 +1431,8 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
 	 */
 	case BOOK3S_INTERRUPT_H_DATA_STORAGE:
 		r = RESUME_PAGE_FAULT;
+		if (vcpu->arch.fault_dsisr == HDSISR_CANARY)
+			r = RESUME_GUEST; /* Just retry if it's the canary */
 		break;
 	case BOOK3S_INTERRUPT_H_INST_STORAGE:
 		vcpu->arch.fault_dar = kvmppc_get_pc(vcpu);
@@ -3690,6 +3692,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	u64 tb, next_timer;
 	int trap, save_pmu;
 
+	WARN_ON_ONCE(vcpu->arch.ceded);
+
 	tb = mftb();
 	next_timer = timer_get_next_tb();
 	if (tb >= next_timer)
@@ -3698,8 +3702,6 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	if (next_timer < time_limit)
 		time_limit = next_timer;
 
-	vcpu->arch.ceded = 0;
-
 	kvmhv_save_host_pmu();		/* saves it to PACA kvm_hstate */
 
 	kvmppc_subcore_enter_guest();
@@ -3826,9 +3828,10 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 			}
 		}
 		kvmppc_xive_pull_vcpu(vcpu);
+
+		vcpu->arch.slb_max = 0;
 	}
 
-	vcpu->arch.slb_max = 0;
 	dec = mfspr(SPRN_DEC);
 	if (!(lpcr & LPCR_LD)) /* Sign extend if not using large decrementer */
 		dec = (s32) dec;
diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
new file mode 100644
index 000000000000..3151b3d62c01
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/kernel.h>
+#include <linux/kvm_host.h>
+#include <asm/asm-prototypes.h>
+#include <asm/dbell.h>
+#include <asm/kvm_ppc.h>
+
+#ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
+static void __start_timing(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator *next)
+{
+	struct kvmppc_vcore *vc = vcpu->arch.vcore;
+	u64 tb = mftb() - vc->tb_offset_applied;
+
+	vcpu->arch.cur_activity = next;
+	vcpu->arch.cur_tb_start = tb;
+}
+
+static void __accumulate_time(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator *next)
+{
+	struct kvmppc_vcore *vc = vcpu->arch.vcore;
+	struct kvmhv_tb_accumulator *curr;
+	u64 tb = mftb() - vc->tb_offset_applied;
+	u64 prev_tb;
+	u64 delta;
+	u64 seq;
+
+	curr = vcpu->arch.cur_activity;
+	vcpu->arch.cur_activity = next;
+	prev_tb = vcpu->arch.cur_tb_start;
+	vcpu->arch.cur_tb_start = tb;
+
+	if (!curr)
+		return;
+
+	delta = tb - prev_tb;
+
+	seq = curr->seqcount;
+	curr->seqcount = seq + 1;
+	smp_wmb();
+	curr->tb_total += delta;
+	if (seq == 0 || delta < curr->tb_min)
+		curr->tb_min = delta;
+	if (delta > curr->tb_max)
+		curr->tb_max = delta;
+	smp_wmb();
+	curr->seqcount = seq + 2;
+}
+
+#define start_timing(vcpu, next) __start_timing(vcpu, next)
+#define end_timing(vcpu) __start_timing(vcpu, NULL)
+#define accumulate_time(vcpu, next) __accumulate_time(vcpu, next)
+#else
+#define start_timing(vcpu, next) do {} while (0)
+#define end_timing(vcpu) do {} while (0)
+#define accumulate_time(vcpu, next) do {} while (0)
+#endif
+
+static inline void mfslb(unsigned int idx, u64 *slbee, u64 *slbev)
+{
+	asm volatile("slbmfev  %0,%1" : "=r" (*slbev) : "r" (idx));
+	asm volatile("slbmfee  %0,%1" : "=r" (*slbee) : "r" (idx));
+}
+
+static inline void mtslb(unsigned int idx, u64 slbee, u64 slbev)
+{
+	BUG_ON((slbee & 0xfff) != idx);
+
+	asm volatile("slbmte %0,%1" :: "r" (slbev), "r" (slbee));
+}
+
+static inline void slb_invalidate(unsigned int ih)
+{
+	asm volatile("slbia %0" :: "i"(ih));
+}
+
+/*
+ * Malicious or buggy radix guests may have inserted SLB entries
+ * (only 0..3 because radix always runs with UPRT=1), so these must
+ * be cleared here to avoid side-channels. slbmte is used rather
+ * than slbia, as it won't clear cached translations.
+ */
+static void radix_clear_slb(void)
+{
+	u64 slbee, slbev;
+	int i;
+
+	for (i = 0; i < 4; i++) {
+		mfslb(i, &slbee, &slbev);
+		if (unlikely(slbee || slbev)) {
+			slbee = i;
+			slbev = 0;
+			mtslb(i, slbee, slbev);
+		}
+	}
+}
+
+int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu)
+{
+	u64 *exsave;
+	unsigned long msr = mfmsr();
+	int trap;
+
+	start_timing(vcpu, &vcpu->arch.rm_entry);
+
+	vcpu->arch.ceded = 0;
+
+	WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_HV);
+	WARN_ON_ONCE(!(vcpu->arch.shregs.msr & MSR_ME));
+
+	mtspr(SPRN_HSRR0, vcpu->arch.regs.nip);
+	mtspr(SPRN_HSRR1, (vcpu->arch.shregs.msr & ~MSR_HV) | MSR_ME);
+
+	/*
+	 * On POWER9 DD2.1 and below, sometimes on a Hypervisor Data Storage
+	 * Interrupt (HDSI) the HDSISR is not be updated at all.
+	 *
+	 * To work around this we put a canary value into the HDSISR before
+	 * returning to a guest and then check for this canary when we take a
+	 * HDSI. If we find the canary on a HDSI, we know the hardware didn't
+	 * update the HDSISR. In this case we return to the guest to retake the
+	 * HDSI which should correctly update the HDSISR the second time HDSI
+	 * entry.
+	 *
+	 * Just do this on all p9 processors for now.
+	 */
+	mtspr(SPRN_HDSISR, HDSISR_CANARY);
+
+	accumulate_time(vcpu, &vcpu->arch.guest_time);
+
+	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_GUEST_HV_FAST;
+	kvmppc_p9_enter_guest(vcpu);
+	// Radix host and guest means host never runs with guest MMU state
+	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_NONE;
+
+	accumulate_time(vcpu, &vcpu->arch.rm_intr);
+
+	/* Get these from r11/12 and paca exsave */
+	vcpu->arch.shregs.srr0 = mfspr(SPRN_SRR0);
+	vcpu->arch.shregs.srr1 = mfspr(SPRN_SRR1);
+	vcpu->arch.shregs.dar = mfspr(SPRN_DAR);
+	vcpu->arch.shregs.dsisr = mfspr(SPRN_DSISR);
+
+	/* 0x2 bit for HSRR is only used by PR and P7/8 HV paths, clear it */
+	trap = local_paca->kvm_hstate.scratch0 & ~0x2;
+	if (likely(trap > BOOK3S_INTERRUPT_MACHINE_CHECK)) {
+		exsave = local_paca->exgen;
+	} else if (trap == BOOK3S_INTERRUPT_SYSTEM_RESET) {
+		exsave = local_paca->exnmi;
+	} else { /* trap == 0x200 */
+		exsave = local_paca->exmc;
+	}
+
+	vcpu->arch.regs.gpr[1] = local_paca->kvm_hstate.scratch1;
+	vcpu->arch.regs.gpr[3] = local_paca->kvm_hstate.scratch2;
+	vcpu->arch.regs.gpr[9] = exsave[EX_R9/sizeof(u64)];
+	vcpu->arch.regs.gpr[10] = exsave[EX_R10/sizeof(u64)];
+	vcpu->arch.regs.gpr[11] = exsave[EX_R11/sizeof(u64)];
+	vcpu->arch.regs.gpr[12] = exsave[EX_R12/sizeof(u64)];
+	vcpu->arch.regs.gpr[13] = exsave[EX_R13/sizeof(u64)];
+	vcpu->arch.ppr = exsave[EX_PPR/sizeof(u64)];
+	vcpu->arch.cfar = exsave[EX_CFAR/sizeof(u64)];
+	vcpu->arch.regs.ctr = exsave[EX_CTR/sizeof(u64)];
+
+	vcpu->arch.last_inst = KVM_INST_FETCH_FAILED;
+
+	if (unlikely(trap == BOOK3S_INTERRUPT_MACHINE_CHECK)) {
+		vcpu->arch.fault_dar = exsave[EX_DAR/sizeof(u64)];
+		vcpu->arch.fault_dsisr = exsave[EX_DSISR/sizeof(u64)];
+		kvmppc_realmode_machine_check(vcpu);
+
+	} else if (unlikely(trap == BOOK3S_INTERRUPT_HMI)) {
+		kvmppc_realmode_hmi_handler();
+
+	} else if (trap == BOOK3S_INTERRUPT_H_EMUL_ASSIST) {
+		vcpu->arch.emul_inst = mfspr(SPRN_HEIR);
+
+	} else if (trap == BOOK3S_INTERRUPT_H_DATA_STORAGE) {
+		vcpu->arch.fault_dar = exsave[EX_DAR/sizeof(u64)];
+		vcpu->arch.fault_dsisr = exsave[EX_DSISR/sizeof(u64)];
+		vcpu->arch.fault_gpa = mfspr(SPRN_ASDR);
+
+	} else if (trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
+		vcpu->arch.fault_gpa = mfspr(SPRN_ASDR);
+
+	} else if (trap == BOOK3S_INTERRUPT_H_FAC_UNAVAIL) {
+		vcpu->arch.hfscr = mfspr(SPRN_HFSCR);
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/*
+	 * Softpatch interrupt for transactional memory emulation cases
+	 * on POWER9 DD2.2.  This is early in the guest exit path - we
+	 * haven't saved registers or done a treclaim yet.
+	 */
+	} else if (trap == BOOK3S_INTERRUPT_HV_SOFTPATCH) {
+		vcpu->arch.emul_inst = mfspr(SPRN_HEIR);
+
+		/*
+		 * The cases we want to handle here are those where the guest
+		 * is in real suspend mode and is trying to transition to
+		 * transactional mode.
+		 */
+		if (local_paca->kvm_hstate.fake_suspend &&
+				(vcpu->arch.shregs.msr & MSR_TS_S)) {
+			if (kvmhv_p9_tm_emulation_early(vcpu)) {
+				/* Prevent it being handled again. */
+				trap = 0;
+			}
+		}
+#endif
+	}
+
+	radix_clear_slb();
+
+	__mtmsrd(msr, 0);
+	mtspr(SPRN_CTRLT, 1);
+
+	accumulate_time(vcpu, &vcpu->arch.rm_exit);
+
+	end_timing(vcpu);
+
+	return trap;
+}
+EXPORT_SYMBOL_GPL(__kvmhv_vcpu_entry_p9);
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 2d0d14ed1d92..6118e8a97ddd 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -44,9 +44,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 #define NAPPING_UNSPLIT	3
 
 /* Stack frame offsets for kvmppc_hv_entry */
-#define SFS			208
+#define SFS			160
 #define STACK_SLOT_TRAP		(SFS-4)
-#define STACK_SLOT_SHORT_PATH	(SFS-8)
 #define STACK_SLOT_TID		(SFS-16)
 #define STACK_SLOT_PSSCR	(SFS-24)
 #define STACK_SLOT_PID		(SFS-32)
@@ -59,8 +58,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 #define STACK_SLOT_UAMOR	(SFS-88)
 #define STACK_SLOT_DAWR1	(SFS-96)
 #define STACK_SLOT_DAWRX1	(SFS-104)
-/* the following is used by the P9 short path */
-#define STACK_SLOT_NVGPRS	(SFS-152)	/* 18 gprs */
 
 /*
  * Call kvmppc_hv_entry in real mode.
@@ -1008,9 +1005,6 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
 no_xive:
 #endif /* CONFIG_KVM_XICS */
 
-	li	r0, 0
-	stw	r0, STACK_SLOT_SHORT_PATH(r1)
-
 deliver_guest_interrupt:	/* r4 = vcpu, r13 = paca */
 	/* Check if we can deliver an external or decrementer interrupt now */
 	ld	r0, VCPU_PENDING_EXC(r4)
@@ -1030,7 +1024,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	mtspr	SPRN_SRR0, r6
 	mtspr	SPRN_SRR1, r7
 
-fast_guest_entry_c:
 	ld	r10, VCPU_PC(r4)
 	ld	r11, VCPU_MSR(r4)
 	/* r11 = vcpu->arch.msr & ~MSR_HV */
@@ -1135,97 +1128,6 @@ ret_to_ultra:
 	ld	r4, VCPU_GPR(R4)(r4)
 	sc	2
 
-/*
- * Enter the guest on a P9 or later system where we have exactly
- * one vcpu per vcore and we don't need to go to real mode
- * (which implies that host and guest are both using radix MMU mode).
- * r3 = vcpu pointer
- * Most SPRs and all the VSRs have been loaded already.
- */
-_GLOBAL(__kvmhv_vcpu_entry_p9)
-EXPORT_SYMBOL_GPL(__kvmhv_vcpu_entry_p9)
-	mflr	r0
-	std	r0, PPC_LR_STKOFF(r1)
-	stdu	r1, -SFS(r1)
-
-	li	r0, 1
-	stw	r0, STACK_SLOT_SHORT_PATH(r1)
-
-	std	r3, HSTATE_KVM_VCPU(r13)
-	mfcr	r4
-	stw	r4, SFS+8(r1)
-
-	std	r1, HSTATE_HOST_R1(r13)
-
-	reg = 14
-	.rept	18
-	std	reg, STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1)
-	reg = reg + 1
-	.endr
-
-	reg = 14
-	.rept	18
-	ld	reg, __VCPU_GPR(reg)(r3)
-	reg = reg + 1
-	.endr
-
-	mfmsr	r10
-	std	r10, HSTATE_HOST_MSR(r13)
-
-	mr	r4, r3
-	b	fast_guest_entry_c
-guest_exit_short_path:
-	/*
-	 * Malicious or buggy radix guests may have inserted SLB entries
-	 * (only 0..3 because radix always runs with UPRT=1), so these must
-	 * be cleared here to avoid side-channels. slbmte is used rather
-	 * than slbia, as it won't clear cached translations.
-	 */
-	li	r0,0
-	slbmte	r0,r0
-	li	r4,1
-	slbmte	r0,r4
-	li	r4,2
-	slbmte	r0,r4
-	li	r4,3
-	slbmte	r0,r4
-
-	li	r0, KVM_GUEST_MODE_NONE
-	stb	r0, HSTATE_IN_GUEST(r13)
-
-	reg = 14
-	.rept	18
-	std	reg, __VCPU_GPR(reg)(r9)
-	reg = reg + 1
-	.endr
-
-	reg = 14
-	.rept	18
-	ld	reg, STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1)
-	reg = reg + 1
-	.endr
-
-	lwz	r4, SFS+8(r1)
-	mtcr	r4
-
-	mr	r3, r12		/* trap number */
-
-	addi	r1, r1, SFS
-	ld	r0, PPC_LR_STKOFF(r1)
-	mtlr	r0
-
-	/* If we are in real mode, do a rfid to get back to the caller */
-	mfmsr	r4
-	andi.	r5, r4, MSR_IR
-	bnelr
-	rldicl	r5, r4, 64 - MSR_TS_S_LG, 62	/* extract TS field */
-	mtspr	SPRN_SRR0, r0
-	ld	r10, HSTATE_HOST_MSR(r13)
-	rldimi	r10, r5, MSR_TS_S_LG, 63 - MSR_TS_T_LG
-	mtspr	SPRN_SRR1, r10
-	RFI_TO_KERNEL
-	b	.
-
 secondary_too_late:
 	li	r12, 0
 	stw	r12, STACK_SLOT_TRAP(r1)
@@ -1397,14 +1299,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	mr	r4,r9
 	bge	fast_guest_return
 2:
-	/* If we came in through the P9 short path, no real mode hcalls */
-	lwz	r0, STACK_SLOT_SHORT_PATH(r1)
-	cmpwi	r0, 0
-	bne	no_try_real
 	/* See if this is an hcall we can handle in real mode */
 	cmpwi	r12,BOOK3S_INTERRUPT_SYSCALL
 	beq	hcall_try_real_mode
-no_try_real:
 
 	/* Hypervisor doorbell - exit only if host IPI flag set */
 	cmpwi	r12, BOOK3S_INTERRUPT_H_DOORBELL
@@ -1447,11 +1344,6 @@ guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
 	bl	kvmhv_accumulate_time
 #endif
 #ifdef CONFIG_KVM_XICS
-	/* If we came in through the P9 short path, xive pull is done in C */
-	lwz	r0, STACK_SLOT_SHORT_PATH(r1)
-	cmpwi	r0, 0
-	bne	1f
-
 	/* We are exiting, pull the VP from the XIVE */
 	lbz	r0, VCPU_XIVE_PUSHED(r9)
 	cmpwi	cr0, r0, 0
@@ -1496,11 +1388,6 @@ guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
 1:	nop
 	patch_site 1b patch__call_kvm_flush_link_stack
 
-	/* If we came in through the P9 short path, go back out to C now */
-	lwz	r0, STACK_SLOT_SHORT_PATH(r1)
-	cmpwi	r0, 0
-	bne	guest_exit_short_path
-
 	/* For hash guest, read the guest SLB and save it away */
 	ld	r5, VCPU_KVM(r9)
 	lbz	r0, KVM_RADIX(r5)
@@ -1548,8 +1435,10 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
 	b	guest_bypass
 
 0:	/*
-	 * Sanitise radix guest SLB, see guest_exit_short_path comment.
-	 * We clear vcpu->arch.slb_max to match earlier behaviour.
+	 * Malicious or buggy radix guests may have inserted SLB entries
+	 * (only 0..3 because radix always runs with UPRT=1), so these must
+	 * be cleared here to avoid side-channels. slbmte is used rather
+	 * than slbia, as it won't clear cached translations.
 	 */
 	li	r0,0
 	stw	r0,VCPU_SLB_MAX(r9)
@@ -3362,7 +3251,7 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_DAWRX1, r0
 END_FTR_SECTION_IFSET(CPU_FTR_DAWR1)
 
-	/* Clear hash and radix guest SLB, see guest_exit_short_path comment. */
+	/* Clear hash and radix guest SLB. */
 	slbmte	r0, r0
 	PPC_SLBIA(6)
 
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 30/46] KVM: PPC: Book3S HV P9: inline kvmhv_load_hv_regs_and_go into __kvmhv_vcpu_entry_p9
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin, Fabiano Rosas
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Now the initial C implementation is done, inline more HV code to make
rearranging things easier.

And rename __kvmhv_vcpu_entry_p9 to drop the leading underscores as it's
now C, and is now a more complete vcpu entry.

Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/include/asm/kvm_book3s_64.h |   2 +-
 arch/powerpc/kvm/book3s_hv.c             | 192 +----------------------
 arch/powerpc/kvm/book3s_hv_interrupt.c   | 179 ++++++++++++++++++++-
 3 files changed, 180 insertions(+), 193 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index c214bcffb441..eaf3a562bf1e 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -153,7 +153,7 @@ static inline bool kvmhv_vcpu_is_radix(struct kvm_vcpu *vcpu)
 	return radix;
 }
 
-int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu);
+int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpcr);
 
 #define KVM_DEFAULT_HPT_ORDER	24	/* 16MB HPT by default */
 #endif
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 6dca639ed997..52f844a06899 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3481,194 +3481,6 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 	trace_kvmppc_run_core(vc, 1);
 }
 
-static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
-{
-	struct kvmppc_vcore *vc = vcpu->arch.vcore;
-	struct kvm_nested_guest *nested = vcpu->arch.nested;
-	u32 lpid;
-
-	lpid = nested ? nested->shadow_lpid : kvm->arch.lpid;
-
-	/*
-	 * All the isync()s are overkill but trivially follow the ISA
-	 * requirements. Some can likely be replaced with justification
-	 * comment for why they are not needed.
-	 */
-	isync();
-	mtspr(SPRN_LPID, lpid);
-	isync();
-	mtspr(SPRN_LPCR, lpcr);
-	isync();
-	mtspr(SPRN_PID, vcpu->arch.pid);
-	isync();
-
-	/* TLBIEL must have LPIDR set, so set guest LPID before flushing. */
-	kvmppc_check_need_tlb_flush(kvm, vc->pcpu, nested);
-}
-
-static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
-{
-	isync();
-	mtspr(SPRN_PID, pid);
-	isync();
-	mtspr(SPRN_LPID, kvm->arch.host_lpid);
-	isync();
-	mtspr(SPRN_LPCR, kvm->arch.host_lpcr);
-	isync();
-}
-
-/*
- * Load up hypervisor-mode registers on P9.
- */
-static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
-				     unsigned long lpcr)
-{
-	struct kvm *kvm = vcpu->kvm;
-	struct kvmppc_vcore *vc = vcpu->arch.vcore;
-	s64 hdec;
-	u64 tb, purr, spurr;
-	int trap;
-	unsigned long host_hfscr = mfspr(SPRN_HFSCR);
-	unsigned long host_ciabr = mfspr(SPRN_CIABR);
-	unsigned long host_dawr0 = mfspr(SPRN_DAWR0);
-	unsigned long host_dawrx0 = mfspr(SPRN_DAWRX0);
-	unsigned long host_psscr = mfspr(SPRN_PSSCR);
-	unsigned long host_pidr = mfspr(SPRN_PID);
-	unsigned long host_dawr1 = 0;
-	unsigned long host_dawrx1 = 0;
-
-	if (cpu_has_feature(CPU_FTR_DAWR1)) {
-		host_dawr1 = mfspr(SPRN_DAWR1);
-		host_dawrx1 = mfspr(SPRN_DAWRX1);
-	}
-
-	tb = mftb();
-	hdec = time_limit - tb;
-	if (hdec < 0)
-		return BOOK3S_INTERRUPT_HV_DECREMENTER;
-
-	if (vc->tb_offset) {
-		u64 new_tb = tb + vc->tb_offset;
-		mtspr(SPRN_TBU40, new_tb);
-		tb = mftb();
-		if ((tb & 0xffffff) < (new_tb & 0xffffff))
-			mtspr(SPRN_TBU40, new_tb + 0x1000000);
-		vc->tb_offset_applied = vc->tb_offset;
-	}
-
-	if (vc->pcr)
-		mtspr(SPRN_PCR, vc->pcr | PCR_MASK);
-	mtspr(SPRN_DPDES, vc->dpdes);
-	mtspr(SPRN_VTB, vc->vtb);
-
-	local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR);
-	local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR);
-	mtspr(SPRN_PURR, vcpu->arch.purr);
-	mtspr(SPRN_SPURR, vcpu->arch.spurr);
-
-	if (dawr_enabled()) {
-		mtspr(SPRN_DAWR0, vcpu->arch.dawr0);
-		mtspr(SPRN_DAWRX0, vcpu->arch.dawrx0);
-		if (cpu_has_feature(CPU_FTR_DAWR1)) {
-			mtspr(SPRN_DAWR1, vcpu->arch.dawr1);
-			mtspr(SPRN_DAWRX1, vcpu->arch.dawrx1);
-		}
-	}
-	mtspr(SPRN_CIABR, vcpu->arch.ciabr);
-	mtspr(SPRN_IC, vcpu->arch.ic);
-
-	mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
-	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
-
-	mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
-
-	mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
-	mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
-	mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
-	mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
-
-	mtspr(SPRN_AMOR, ~0UL);
-
-	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
-
-	/*
-	 * P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
-	 * so set guest LPCR (with HDICE) before writing HDEC.
-	 */
-	mtspr(SPRN_HDEC, hdec);
-
-	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
-	mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
-
-	trap = __kvmhv_vcpu_entry_p9(vcpu);
-
-	/* Advance host PURR/SPURR by the amount used by guest */
-	purr = mfspr(SPRN_PURR);
-	spurr = mfspr(SPRN_SPURR);
-	mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr +
-	      purr - vcpu->arch.purr);
-	mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr +
-	      spurr - vcpu->arch.spurr);
-	vcpu->arch.purr = purr;
-	vcpu->arch.spurr = spurr;
-
-	vcpu->arch.ic = mfspr(SPRN_IC);
-	vcpu->arch.pid = mfspr(SPRN_PID);
-	vcpu->arch.psscr = mfspr(SPRN_PSSCR) & PSSCR_GUEST_VIS;
-
-	vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0);
-	vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1);
-	vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2);
-	vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3);
-
-	/* Preserve PSSCR[FAKE_SUSPEND] until we've called kvmppc_save_tm_hv */
-	mtspr(SPRN_PSSCR, host_psscr |
-	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
-	mtspr(SPRN_HFSCR, host_hfscr);
-	mtspr(SPRN_CIABR, host_ciabr);
-	mtspr(SPRN_DAWR0, host_dawr0);
-	mtspr(SPRN_DAWRX0, host_dawrx0);
-	if (cpu_has_feature(CPU_FTR_DAWR1)) {
-		mtspr(SPRN_DAWR1, host_dawr1);
-		mtspr(SPRN_DAWRX1, host_dawrx1);
-	}
-
-	/*
-	 * Since this is radix, do a eieio; tlbsync; ptesync sequence in
-	 * case we interrupted the guest between a tlbie and a ptesync.
-	 */
-	asm volatile("eieio; tlbsync; ptesync");
-
-	/*
-	 * cp_abort is required if the processor supports local copy-paste
-	 * to clear the copy buffer that was under control of the guest.
-	 */
-	if (cpu_has_feature(CPU_FTR_ARCH_31))
-		asm volatile(PPC_CP_ABORT);
-
-	vc->dpdes = mfspr(SPRN_DPDES);
-	vc->vtb = mfspr(SPRN_VTB);
-	mtspr(SPRN_DPDES, 0);
-	if (vc->pcr)
-		mtspr(SPRN_PCR, PCR_MASK);
-
-	if (vc->tb_offset_applied) {
-		u64 new_tb = mftb() - vc->tb_offset_applied;
-		mtspr(SPRN_TBU40, new_tb);
-		tb = mftb();
-		if ((tb & 0xffffff) < (new_tb & 0xffffff))
-			mtspr(SPRN_TBU40, new_tb + 0x1000000);
-		vc->tb_offset_applied = 0;
-	}
-
-	/* HDEC must be at least as large as DEC, so decrementer_max fits */
-	mtspr(SPRN_HDEC, decrementer_max);
-
-	switch_mmu_to_host_radix(kvm, host_pidr);
-
-	return trap;
-}
-
 static inline bool hcall_is_xics(unsigned long req)
 {
 	return (req == H_EOI || req == H_CPPR || req == H_IPI ||
@@ -3766,7 +3578,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 		 * We need to save and restore the guest visible part of the
 		 * psscr (i.e. using SPRN_PSSCR_PR) since the hypervisor
 		 * doesn't do this for us. Note only required if pseries since
-		 * this is done in kvmhv_load_hv_regs_and_go() below otherwise.
+		 * this is done in kvmhv_vcpu_entry_p9() below otherwise.
 		 */
 		unsigned long host_psscr;
 		/* call our hypervisor to load up HV regs and go */
@@ -3804,7 +3616,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 		}
 	} else {
 		kvmppc_xive_push_vcpu(vcpu);
-		trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit, lpcr);
+		trap = kvmhv_vcpu_entry_p9(vcpu, time_limit, lpcr);
 		if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
 		    !(vcpu->arch.shregs.msr & MSR_PR)) {
 			unsigned long req = kvmppc_get_gpr(vcpu, 3);
diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index 3151b3d62c01..c1105a4cc9b7 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -55,6 +55,42 @@ static void __accumulate_time(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator
 #define accumulate_time(vcpu, next) do {} while (0)
 #endif
 
+static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
+{
+	struct kvmppc_vcore *vc = vcpu->arch.vcore;
+	struct kvm_nested_guest *nested = vcpu->arch.nested;
+	u32 lpid;
+
+	lpid = nested ? nested->shadow_lpid : kvm->arch.lpid;
+
+	/*
+	 * All the isync()s are overkill but trivially follow the ISA
+	 * requirements. Some can likely be replaced with justification
+	 * comment for why they are not needed.
+	 */
+	isync();
+	mtspr(SPRN_LPID, lpid);
+	isync();
+	mtspr(SPRN_LPCR, lpcr);
+	isync();
+	mtspr(SPRN_PID, vcpu->arch.pid);
+	isync();
+
+	/* TLBIEL must have LPIDR set, so set guest LPID before flushing. */
+	kvmppc_check_need_tlb_flush(kvm, vc->pcpu, nested);
+}
+
+static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
+{
+	isync();
+	mtspr(SPRN_PID, pid);
+	isync();
+	mtspr(SPRN_LPID, kvm->arch.host_lpid);
+	isync();
+	mtspr(SPRN_LPCR, kvm->arch.host_lpcr);
+	isync();
+}
+
 static inline void mfslb(unsigned int idx, u64 *slbee, u64 *slbev)
 {
 	asm volatile("slbmfev  %0,%1" : "=r" (*slbev) : "r" (idx));
@@ -94,11 +130,86 @@ static void radix_clear_slb(void)
 	}
 }
 
-int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu)
+int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpcr)
 {
+	struct kvm *kvm = vcpu->kvm;
+	struct kvmppc_vcore *vc = vcpu->arch.vcore;
+	s64 hdec;
+	u64 tb, purr, spurr;
 	u64 *exsave;
 	unsigned long msr = mfmsr();
 	int trap;
+	unsigned long host_hfscr = mfspr(SPRN_HFSCR);
+	unsigned long host_ciabr = mfspr(SPRN_CIABR);
+	unsigned long host_dawr0 = mfspr(SPRN_DAWR0);
+	unsigned long host_dawrx0 = mfspr(SPRN_DAWRX0);
+	unsigned long host_psscr = mfspr(SPRN_PSSCR);
+	unsigned long host_pidr = mfspr(SPRN_PID);
+	unsigned long host_dawr1 = 0;
+	unsigned long host_dawrx1 = 0;
+
+	if (cpu_has_feature(CPU_FTR_DAWR1)) {
+		host_dawr1 = mfspr(SPRN_DAWR1);
+		host_dawrx1 = mfspr(SPRN_DAWRX1);
+	}
+
+	tb = mftb();
+	hdec = time_limit - tb;
+	if (hdec < 0)
+		return BOOK3S_INTERRUPT_HV_DECREMENTER;
+
+	if (vc->tb_offset) {
+		u64 new_tb = tb + vc->tb_offset;
+		mtspr(SPRN_TBU40, new_tb);
+		tb = mftb();
+		if ((tb & 0xffffff) < (new_tb & 0xffffff))
+			mtspr(SPRN_TBU40, new_tb + 0x1000000);
+		vc->tb_offset_applied = vc->tb_offset;
+	}
+
+	if (vc->pcr)
+		mtspr(SPRN_PCR, vc->pcr | PCR_MASK);
+	mtspr(SPRN_DPDES, vc->dpdes);
+	mtspr(SPRN_VTB, vc->vtb);
+
+	local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR);
+	local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR);
+	mtspr(SPRN_PURR, vcpu->arch.purr);
+	mtspr(SPRN_SPURR, vcpu->arch.spurr);
+
+	if (dawr_enabled()) {
+		mtspr(SPRN_DAWR0, vcpu->arch.dawr0);
+		mtspr(SPRN_DAWRX0, vcpu->arch.dawrx0);
+		if (cpu_has_feature(CPU_FTR_DAWR1)) {
+			mtspr(SPRN_DAWR1, vcpu->arch.dawr1);
+			mtspr(SPRN_DAWRX1, vcpu->arch.dawrx1);
+		}
+	}
+	mtspr(SPRN_CIABR, vcpu->arch.ciabr);
+	mtspr(SPRN_IC, vcpu->arch.ic);
+
+	mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
+	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
+
+	mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
+
+	mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
+	mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
+	mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
+	mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
+
+	mtspr(SPRN_AMOR, ~0UL);
+
+	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
+
+	/*
+	 * P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
+	 * so set guest LPCR (with HDICE) before writing HDEC.
+	 */
+	mtspr(SPRN_HDEC, hdec);
+
+	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
+	mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
 
 	start_timing(vcpu, &vcpu->arch.rm_entry);
 
@@ -218,6 +329,70 @@ int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu)
 
 	end_timing(vcpu);
 
+	/* Advance host PURR/SPURR by the amount used by guest */
+	purr = mfspr(SPRN_PURR);
+	spurr = mfspr(SPRN_SPURR);
+	mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr +
+	      purr - vcpu->arch.purr);
+	mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr +
+	      spurr - vcpu->arch.spurr);
+	vcpu->arch.purr = purr;
+	vcpu->arch.spurr = spurr;
+
+	vcpu->arch.ic = mfspr(SPRN_IC);
+	vcpu->arch.pid = mfspr(SPRN_PID);
+	vcpu->arch.psscr = mfspr(SPRN_PSSCR) & PSSCR_GUEST_VIS;
+
+	vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0);
+	vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1);
+	vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2);
+	vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3);
+
+	/* Preserve PSSCR[FAKE_SUSPEND] until we've called kvmppc_save_tm_hv */
+	mtspr(SPRN_PSSCR, host_psscr |
+	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
+	mtspr(SPRN_HFSCR, host_hfscr);
+	mtspr(SPRN_CIABR, host_ciabr);
+	mtspr(SPRN_DAWR0, host_dawr0);
+	mtspr(SPRN_DAWRX0, host_dawrx0);
+	if (cpu_has_feature(CPU_FTR_DAWR1)) {
+		mtspr(SPRN_DAWR1, host_dawr1);
+		mtspr(SPRN_DAWRX1, host_dawrx1);
+	}
+
+	/*
+	 * Since this is radix, do a eieio; tlbsync; ptesync sequence in
+	 * case we interrupted the guest between a tlbie and a ptesync.
+	 */
+	asm volatile("eieio; tlbsync; ptesync");
+
+	/*
+	 * cp_abort is required if the processor supports local copy-paste
+	 * to clear the copy buffer that was under control of the guest.
+	 */
+	if (cpu_has_feature(CPU_FTR_ARCH_31))
+		asm volatile(PPC_CP_ABORT);
+
+	vc->dpdes = mfspr(SPRN_DPDES);
+	vc->vtb = mfspr(SPRN_VTB);
+	mtspr(SPRN_DPDES, 0);
+	if (vc->pcr)
+		mtspr(SPRN_PCR, PCR_MASK);
+
+	if (vc->tb_offset_applied) {
+		u64 new_tb = mftb() - vc->tb_offset_applied;
+		mtspr(SPRN_TBU40, new_tb);
+		tb = mftb();
+		if ((tb & 0xffffff) < (new_tb & 0xffffff))
+			mtspr(SPRN_TBU40, new_tb + 0x1000000);
+		vc->tb_offset_applied = 0;
+	}
+
+	/* HDEC must be at least as large as DEC, so decrementer_max fits */
+	mtspr(SPRN_HDEC, decrementer_max);
+
+	switch_mmu_to_host_radix(kvm, host_pidr);
+
 	return trap;
 }
-EXPORT_SYMBOL_GPL(__kvmhv_vcpu_entry_p9);
+EXPORT_SYMBOL_GPL(kvmhv_vcpu_entry_p9);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 31/46] KVM: PPC: Book3S HV P9: Read machine check registers while MSR[RI] is 0
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

SRR0/1, DAR, DSISR must all be protected from machine check which can
clobber them. Ensure MSR[RI] is clear while they are live.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c           | 11 +++++++--
 arch/powerpc/kvm/book3s_hv_interrupt.c | 33 +++++++++++++++++++++++---
 arch/powerpc/kvm/book3s_hv_ras.c       |  2 ++
 3 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 52f844a06899..98e5ae897fad 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3551,11 +3551,16 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	mtspr(SPRN_BESCR, vcpu->arch.bescr);
 	mtspr(SPRN_WORT, vcpu->arch.wort);
 	mtspr(SPRN_TIDR, vcpu->arch.tid);
-	mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
-	mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
 	mtspr(SPRN_AMR, vcpu->arch.amr);
 	mtspr(SPRN_UAMOR, vcpu->arch.uamor);
 
+	/*
+	 * DAR, DSISR, and for nested HV, SPRGs must be set with MSR[RI]
+	 * clear (or hstate set appropriately to catch those registers
+	 * being clobbered if we take a MCE or SRESET), so those are done
+	 * later.
+	 */
+
 	if (!(vcpu->arch.ctrl & 1))
 		mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
 
@@ -3598,6 +3603,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 			hvregs.vcpu_token = vcpu->vcpu_id;
 		}
 		hvregs.hdec_expiry = time_limit;
+		mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
+		mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
 		trap = plpar_hcall_norets(H_ENTER_NESTED, __pa(&hvregs),
 					  __pa(&vcpu->arch.regs));
 		kvmhv_restore_hv_return_state(vcpu, &hvregs);
diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index c1105a4cc9b7..a7e5628ac36c 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -137,6 +137,7 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	s64 hdec;
 	u64 tb, purr, spurr;
 	u64 *exsave;
+	bool ri_set;
 	unsigned long msr = mfmsr();
 	int trap;
 	unsigned long host_hfscr = mfspr(SPRN_HFSCR);
@@ -208,9 +209,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	 */
 	mtspr(SPRN_HDEC, hdec);
 
-	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
-	mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
-
 	start_timing(vcpu, &vcpu->arch.rm_entry);
 
 	vcpu->arch.ceded = 0;
@@ -236,6 +234,13 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	 */
 	mtspr(SPRN_HDSISR, HDSISR_CANARY);
 
+	__mtmsrd(0, 1); /* clear RI */
+
+	mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
+	mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
+	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
+	mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
+
 	accumulate_time(vcpu, &vcpu->arch.guest_time);
 
 	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_GUEST_HV_FAST;
@@ -253,7 +258,13 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	/* 0x2 bit for HSRR is only used by PR and P7/8 HV paths, clear it */
 	trap = local_paca->kvm_hstate.scratch0 & ~0x2;
+
+	/* HSRR interrupts leave MSR[RI] unchanged, SRR interrupts clear it. */
+	ri_set = false;
 	if (likely(trap > BOOK3S_INTERRUPT_MACHINE_CHECK)) {
+		if (trap != BOOK3S_INTERRUPT_SYSCALL &&
+				(vcpu->arch.shregs.msr & MSR_RI))
+			ri_set = true;
 		exsave = local_paca->exgen;
 	} else if (trap == BOOK3S_INTERRUPT_SYSTEM_RESET) {
 		exsave = local_paca->exnmi;
@@ -263,6 +274,22 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	vcpu->arch.regs.gpr[1] = local_paca->kvm_hstate.scratch1;
 	vcpu->arch.regs.gpr[3] = local_paca->kvm_hstate.scratch2;
+
+	/*
+	 * Only set RI after reading machine check regs (DAR, DSISR, SRR0/1)
+	 * and hstate scratch (which we need to move into exsave to make
+	 * re-entrant vs SRESET/MCE)
+	 */
+	if (ri_set) {
+		if (unlikely(!(mfmsr() & MSR_RI))) {
+			__mtmsrd(MSR_RI, 1);
+			WARN_ON_ONCE(1);
+		}
+	} else {
+		WARN_ON_ONCE(mfmsr() & MSR_RI);
+		__mtmsrd(MSR_RI, 1);
+	}
+
 	vcpu->arch.regs.gpr[9] = exsave[EX_R9/sizeof(u64)];
 	vcpu->arch.regs.gpr[10] = exsave[EX_R10/sizeof(u64)];
 	vcpu->arch.regs.gpr[11] = exsave[EX_R11/sizeof(u64)];
diff --git a/arch/powerpc/kvm/book3s_hv_ras.c b/arch/powerpc/kvm/book3s_hv_ras.c
index d4bca93b79f6..8d8a4d5f0b55 100644
--- a/arch/powerpc/kvm/book3s_hv_ras.c
+++ b/arch/powerpc/kvm/book3s_hv_ras.c
@@ -199,6 +199,8 @@ static void kvmppc_tb_resync_done(void)
  * know about the exact state of the TB value. Resync TB call will
  * restore TB to host timebase.
  *
+ * This could use the new OPAL_HANDLE_HMI2 to avoid resyncing TB every time.
+ *
  * Things to consider:
  * - On TB error, HMI interrupt is reported on all the threads of the core
  *   that has encountered TB error irrespective of split-core mode.
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 32/46] KVM: PPC: Book3S HV P9: Improve exit timing accounting coverage
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

The C conversion caused exit timing to become a bit cramped. Expand it
to cover more of the entry and exit code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv_interrupt.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index a7e5628ac36c..4058a325a7f0 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -159,6 +159,8 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	if (hdec < 0)
 		return BOOK3S_INTERRUPT_HV_DECREMENTER;
 
+	start_timing(vcpu, &vcpu->arch.rm_entry);
+
 	if (vc->tb_offset) {
 		u64 new_tb = tb + vc->tb_offset;
 		mtspr(SPRN_TBU40, new_tb);
@@ -209,8 +211,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	 */
 	mtspr(SPRN_HDEC, hdec);
 
-	start_timing(vcpu, &vcpu->arch.rm_entry);
-
 	vcpu->arch.ceded = 0;
 
 	WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_HV);
@@ -354,8 +354,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	accumulate_time(vcpu, &vcpu->arch.rm_exit);
 
-	end_timing(vcpu);
-
 	/* Advance host PURR/SPURR by the amount used by guest */
 	purr = mfspr(SPRN_PURR);
 	spurr = mfspr(SPRN_SPURR);
@@ -420,6 +418,8 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	switch_mmu_to_host_radix(kvm, host_pidr);
 
+	end_timing(vcpu);
+
 	return trap;
 }
 EXPORT_SYMBOL_GPL(kvmhv_vcpu_entry_p9);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 33/46] KVM: PPC: Book3S HV P9: Move SPR loading after expiry time check
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

This is wasted work if the time limit is exceeded.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv_interrupt.c | 36 ++++++++++++++++----------
 1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index 4058a325a7f0..f57379e73b5c 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -138,21 +138,16 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	u64 tb, purr, spurr;
 	u64 *exsave;
 	bool ri_set;
-	unsigned long msr = mfmsr();
 	int trap;
-	unsigned long host_hfscr = mfspr(SPRN_HFSCR);
-	unsigned long host_ciabr = mfspr(SPRN_CIABR);
-	unsigned long host_dawr0 = mfspr(SPRN_DAWR0);
-	unsigned long host_dawrx0 = mfspr(SPRN_DAWRX0);
-	unsigned long host_psscr = mfspr(SPRN_PSSCR);
-	unsigned long host_pidr = mfspr(SPRN_PID);
-	unsigned long host_dawr1 = 0;
-	unsigned long host_dawrx1 = 0;
-
-	if (cpu_has_feature(CPU_FTR_DAWR1)) {
-		host_dawr1 = mfspr(SPRN_DAWR1);
-		host_dawrx1 = mfspr(SPRN_DAWRX1);
-	}
+	unsigned long msr;
+	unsigned long host_hfscr;
+	unsigned long host_ciabr;
+	unsigned long host_dawr0;
+	unsigned long host_dawrx0;
+	unsigned long host_psscr;
+	unsigned long host_pidr;
+	unsigned long host_dawr1;
+	unsigned long host_dawrx1;
 
 	tb = mftb();
 	hdec = time_limit - tb;
@@ -170,6 +165,19 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 		vc->tb_offset_applied = vc->tb_offset;
 	}
 
+	msr = mfmsr();
+
+	host_hfscr = mfspr(SPRN_HFSCR);
+	host_ciabr = mfspr(SPRN_CIABR);
+	host_dawr0 = mfspr(SPRN_DAWR0);
+	host_dawrx0 = mfspr(SPRN_DAWRX0);
+	host_psscr = mfspr(SPRN_PSSCR);
+	host_pidr = mfspr(SPRN_PID);
+	if (cpu_has_feature(CPU_FTR_DAWR1)) {
+		host_dawr1 = mfspr(SPRN_DAWR1);
+		host_dawrx1 = mfspr(SPRN_DAWRX1);
+	}
+
 	if (vc->pcr)
 		mtspr(SPRN_PCR, vc->pcr | PCR_MASK);
 	mtspr(SPRN_DPDES, vc->dpdes);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 34/46] KVM: PPC: Book3S HV P9: Add helpers for OS SPR handling
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

This is a first step to wrapping supervisor and user SPR saving and
loading up into helpers, which will then be called independently in
bare metal and nested HV cases in order to optimise SPR access.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c | 141 ++++++++++++++++++++++-------------
 1 file changed, 89 insertions(+), 52 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 98e5ae897fad..74c67f713a26 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3481,6 +3481,89 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 	trace_kvmppc_run_core(vc, 1);
 }
 
+static void load_spr_state(struct kvm_vcpu *vcpu)
+{
+	mtspr(SPRN_DSCR, vcpu->arch.dscr);
+	mtspr(SPRN_IAMR, vcpu->arch.iamr);
+	mtspr(SPRN_PSPB, vcpu->arch.pspb);
+	mtspr(SPRN_FSCR, vcpu->arch.fscr);
+	mtspr(SPRN_TAR, vcpu->arch.tar);
+	mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
+	mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
+	mtspr(SPRN_BESCR, vcpu->arch.bescr);
+	mtspr(SPRN_WORT, vcpu->arch.wort);
+	mtspr(SPRN_TIDR, vcpu->arch.tid);
+	mtspr(SPRN_AMR, vcpu->arch.amr);
+	mtspr(SPRN_UAMOR, vcpu->arch.uamor);
+
+	/*
+	 * DAR, DSISR, and for nested HV, SPRGs must be set with MSR[RI]
+	 * clear (or hstate set appropriately to catch those registers
+	 * being clobbered if we take a MCE or SRESET), so those are done
+	 * later.
+	 */
+
+	if (!(vcpu->arch.ctrl & 1))
+		mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
+}
+
+static void store_spr_state(struct kvm_vcpu *vcpu)
+{
+	vcpu->arch.ctrl = mfspr(SPRN_CTRLF);
+
+	vcpu->arch.iamr = mfspr(SPRN_IAMR);
+	vcpu->arch.pspb = mfspr(SPRN_PSPB);
+	vcpu->arch.fscr = mfspr(SPRN_FSCR);
+	vcpu->arch.tar = mfspr(SPRN_TAR);
+	vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
+	vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
+	vcpu->arch.bescr = mfspr(SPRN_BESCR);
+	vcpu->arch.wort = mfspr(SPRN_WORT);
+	vcpu->arch.tid = mfspr(SPRN_TIDR);
+	vcpu->arch.amr = mfspr(SPRN_AMR);
+	vcpu->arch.uamor = mfspr(SPRN_UAMOR);
+	vcpu->arch.dscr = mfspr(SPRN_DSCR);
+}
+
+/*
+ * Privileged (non-hypervisor) host registers to save.
+ */
+struct p9_host_os_sprs {
+	unsigned long dscr;
+	unsigned long tidr;
+	unsigned long iamr;
+	unsigned long amr;
+	unsigned long fscr;
+};
+
+static void save_p9_host_os_sprs(struct p9_host_os_sprs *host_os_sprs)
+{
+	host_os_sprs->dscr = mfspr(SPRN_DSCR);
+	host_os_sprs->tidr = mfspr(SPRN_TIDR);
+	host_os_sprs->iamr = mfspr(SPRN_IAMR);
+	host_os_sprs->amr = mfspr(SPRN_AMR);
+	host_os_sprs->fscr = mfspr(SPRN_FSCR);
+}
+
+/* vcpu guest regs must already be saved */
+static void restore_p9_host_os_sprs(struct kvm_vcpu *vcpu,
+				    struct p9_host_os_sprs *host_os_sprs)
+{
+	mtspr(SPRN_PSPB, 0);
+	mtspr(SPRN_WORT, 0);
+	mtspr(SPRN_UAMOR, 0);
+
+	mtspr(SPRN_DSCR, host_os_sprs->dscr);
+	mtspr(SPRN_TIDR, host_os_sprs->tidr);
+	mtspr(SPRN_IAMR, host_os_sprs->iamr);
+
+	if (host_os_sprs->amr != vcpu->arch.amr)
+		mtspr(SPRN_AMR, host_os_sprs->amr);
+
+	if (host_os_sprs->fscr != vcpu->arch.fscr)
+		mtspr(SPRN_FSCR, host_os_sprs->fscr);
+}
+
 static inline bool hcall_is_xics(unsigned long req)
 {
 	return (req == H_EOI || req == H_CPPR || req == H_IPI ||
@@ -3495,11 +3578,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 			 unsigned long lpcr)
 {
 	struct kvmppc_vcore *vc = vcpu->arch.vcore;
-	unsigned long host_dscr = mfspr(SPRN_DSCR);
-	unsigned long host_tidr = mfspr(SPRN_TIDR);
-	unsigned long host_iamr = mfspr(SPRN_IAMR);
-	unsigned long host_amr = mfspr(SPRN_AMR);
-	unsigned long host_fscr = mfspr(SPRN_FSCR);
+	struct p9_host_os_sprs host_os_sprs;
 	s64 dec;
 	u64 tb, next_timer;
 	int trap, save_pmu;
@@ -3514,6 +3593,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	if (next_timer < time_limit)
 		time_limit = next_timer;
 
+	save_p9_host_os_sprs(&host_os_sprs);
+
 	kvmhv_save_host_pmu();		/* saves it to PACA kvm_hstate */
 
 	kvmppc_subcore_enter_guest();
@@ -3541,28 +3622,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 #endif
 	mtspr(SPRN_VRSAVE, vcpu->arch.vrsave);
 
-	mtspr(SPRN_DSCR, vcpu->arch.dscr);
-	mtspr(SPRN_IAMR, vcpu->arch.iamr);
-	mtspr(SPRN_PSPB, vcpu->arch.pspb);
-	mtspr(SPRN_FSCR, vcpu->arch.fscr);
-	mtspr(SPRN_TAR, vcpu->arch.tar);
-	mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
-	mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
-	mtspr(SPRN_BESCR, vcpu->arch.bescr);
-	mtspr(SPRN_WORT, vcpu->arch.wort);
-	mtspr(SPRN_TIDR, vcpu->arch.tid);
-	mtspr(SPRN_AMR, vcpu->arch.amr);
-	mtspr(SPRN_UAMOR, vcpu->arch.uamor);
-
-	/*
-	 * DAR, DSISR, and for nested HV, SPRGs must be set with MSR[RI]
-	 * clear (or hstate set appropriately to catch those registers
-	 * being clobbered if we take a MCE or SRESET), so those are done
-	 * later.
-	 */
-
-	if (!(vcpu->arch.ctrl & 1))
-		mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
+	load_spr_state(vcpu);
 
 	/*
 	 * When setting DEC, we must always deal with irq_work_raise via NMI vs
@@ -3658,33 +3718,10 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	vcpu->arch.dec_expires = dec + tb;
 	vcpu->cpu = -1;
 	vcpu->arch.thread_cpu = -1;
-	vcpu->arch.ctrl = mfspr(SPRN_CTRLF);
-
-	vcpu->arch.iamr = mfspr(SPRN_IAMR);
-	vcpu->arch.pspb = mfspr(SPRN_PSPB);
-	vcpu->arch.fscr = mfspr(SPRN_FSCR);
-	vcpu->arch.tar = mfspr(SPRN_TAR);
-	vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
-	vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
-	vcpu->arch.bescr = mfspr(SPRN_BESCR);
-	vcpu->arch.wort = mfspr(SPRN_WORT);
-	vcpu->arch.tid = mfspr(SPRN_TIDR);
-	vcpu->arch.amr = mfspr(SPRN_AMR);
-	vcpu->arch.uamor = mfspr(SPRN_UAMOR);
-	vcpu->arch.dscr = mfspr(SPRN_DSCR);
-
-	mtspr(SPRN_PSPB, 0);
-	mtspr(SPRN_WORT, 0);
-	mtspr(SPRN_UAMOR, 0);
-	mtspr(SPRN_DSCR, host_dscr);
-	mtspr(SPRN_TIDR, host_tidr);
-	mtspr(SPRN_IAMR, host_iamr);
 
-	if (host_amr != vcpu->arch.amr)
-		mtspr(SPRN_AMR, host_amr);
+	store_spr_state(vcpu);
 
-	if (host_fscr != vcpu->arch.fscr)
-		mtspr(SPRN_FSCR, host_fscr);
+	restore_p9_host_os_sprs(vcpu, &host_os_sprs);
 
 	msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX);
 	store_fp_state(&vcpu->arch.fp);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 35/46] KVM: PPC: Book3S HV P9: Switch to guest MMU context as late as possible
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Move MMU context switch as late as reasonably possible to minimise code
running with guest context switched in. This becomes more important when
this code may run in real-mode, with later changes.

Move WARN_ON as early as possible so program check interrupts are less
likely to tangle everything up.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv_interrupt.c | 40 +++++++++++++-------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index f57379e73b5c..787a7d2aed1a 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -154,8 +154,13 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	if (hdec < 0)
 		return BOOK3S_INTERRUPT_HV_DECREMENTER;
 
+	WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_HV);
+	WARN_ON_ONCE(!(vcpu->arch.shregs.msr & MSR_ME));
+
 	start_timing(vcpu, &vcpu->arch.rm_entry);
 
+	vcpu->arch.ceded = 0;
+
 	if (vc->tb_offset) {
 		u64 new_tb = tb + vc->tb_offset;
 		mtspr(SPRN_TBU40, new_tb);
@@ -204,26 +209,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
 
-	mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
-	mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
-	mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
-	mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
-
-	mtspr(SPRN_AMOR, ~0UL);
-
-	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
-
-	/*
-	 * P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
-	 * so set guest LPCR (with HDICE) before writing HDEC.
-	 */
-	mtspr(SPRN_HDEC, hdec);
-
-	vcpu->arch.ceded = 0;
-
-	WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_HV);
-	WARN_ON_ONCE(!(vcpu->arch.shregs.msr & MSR_ME));
-
 	mtspr(SPRN_HSRR0, vcpu->arch.regs.nip);
 	mtspr(SPRN_HSRR1, (vcpu->arch.shregs.msr & ~MSR_HV) | MSR_ME);
 
@@ -242,6 +227,21 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	 */
 	mtspr(SPRN_HDSISR, HDSISR_CANARY);
 
+	mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
+	mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
+	mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
+	mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
+
+	mtspr(SPRN_AMOR, ~0UL);
+
+	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
+
+	/*
+	 * P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
+	 * so set guest LPCR (with HDICE) before writing HDEC.
+	 */
+	mtspr(SPRN_HDEC, hdec);
+
 	__mtmsrd(0, 1); /* clear RI */
 
 	mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 36/46] KVM: PPC: Book3S HV: Implement radix prefetch workaround by disabling MMU
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Rather than partition the guest PID space + flush a rogue guest PID to
work around this problem, instead fix it by always disabling the MMU when
switching in or out of guest MMU context in HV mode.

This may be a bit less efficient, but it is a lot less complicated and
allows the P9 path to trivally implement the workaround too. Newer CPUs
are not subject to this issue.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/include/asm/mmu_context.h   |  6 ----
 arch/powerpc/kvm/book3s_hv.c             | 21 +++++++----
 arch/powerpc/kvm/book3s_hv_interrupt.c   | 16 ++++++---
 arch/powerpc/kvm/book3s_hv_rmhandlers.S  | 34 ------------------
 arch/powerpc/mm/book3s64/radix_pgtable.c | 27 +++++---------
 arch/powerpc/mm/book3s64/radix_tlb.c     | 46 ------------------------
 arch/powerpc/mm/mmu_context.c            |  4 +--
 7 files changed, 36 insertions(+), 118 deletions(-)

diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 652ce85f9410..bb5c7e5e142e 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -122,12 +122,6 @@ static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
 }
 #endif
 
-#if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
-extern void radix_kvm_prefetch_workaround(struct mm_struct *mm);
-#else
-static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { }
-#endif
-
 extern void switch_cop(struct mm_struct *next);
 extern int use_cop(unsigned long acop, struct mm_struct *mm);
 extern void drop_cop(unsigned long acop, struct mm_struct *mm);
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 74c67f713a26..8480cbe4b4fa 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -809,6 +809,9 @@ static int kvmppc_h_set_mode(struct kvm_vcpu *vcpu, unsigned long mflags,
 		 */
 		if (mflags != 0 && mflags != 3)
 			return H_UNSUPPORTED_FLAG_START;
+		if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG) &&
+				kvmhv_vcpu_is_radix(vcpu) && mflags == 3)
+			return H_UNSUPPORTED_FLAG_START;
 		return H_TOO_HARD;
 	default:
 		return H_TOO_HARD;
@@ -1665,6 +1668,14 @@ unsigned long kvmppc_filter_lpcr_hv(struct kvmppc_vcore *vc, unsigned long lpcr)
 		lpcr &= ~LPCR_AIL;
 	if ((lpcr & LPCR_AIL) != LPCR_AIL_3)
 		lpcr &= ~LPCR_AIL; /* LPCR[AIL]=1/2 is disallowed */
+	/*
+	 * On some POWER9s we force AIL off for radix guests to prevent
+	 * executing in MSR[HV]=1 mode with the MMU enabled and PIDR set to
+	 * guest, which can result in Q0 translations with LPID=0 PID=PIDR to
+	 * be cached, which the host TLB management does not expect.
+	 */
+	if (kvm_is_radix(kvm) && cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+		lpcr &= ~LPCR_AIL;
 
 	/*
 	 * On POWER9, allow userspace to enable large decrementer for the
@@ -4334,12 +4345,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
 	vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
 
 	do {
-		/*
-		 * The TLB prefetch bug fixup is only in the kvmppc_run_vcpu
-		 * path, which also handles hash and dependent threads mode.
-		 */
-		if (kvm->arch.threads_indep && kvm_is_radix(kvm) &&
-		    !cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+		if (kvm->arch.threads_indep && kvm_is_radix(kvm))
 			r = kvmhv_run_single_vcpu(vcpu, ~(u64)0,
 						  vcpu->arch.vcore->lpcr);
 		else
@@ -4962,6 +4968,9 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm)
 		if (!indep_threads_mode && !cpu_has_feature(CPU_FTR_HVMODE)) {
 			pr_warn("KVM: Ignoring indep_threads_mode=N in nested hypervisor\n");
 			kvm->arch.threads_indep = true;
+		} else if (!indep_threads_mode && cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) {
+			pr_warn("KVM: Ignoring indep_threads_mode=N on pre-DD2.2 POWER9\n");
+			kvm->arch.threads_indep = true;
 		} else {
 			kvm->arch.threads_indep = indep_threads_mode;
 		}
diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index 787a7d2aed1a..cd84d2c37632 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -234,6 +234,9 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	mtspr(SPRN_AMOR, ~0UL);
 
+	if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+		__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
+
 	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
 
 	/*
@@ -242,7 +245,8 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	 */
 	mtspr(SPRN_HDEC, hdec);
 
-	__mtmsrd(0, 1); /* clear RI */
+	if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+		__mtmsrd(0, 1); /* clear RI */
 
 	mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
 	mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
@@ -357,9 +361,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	radix_clear_slb();
 
-	__mtmsrd(msr, 0);
-	mtspr(SPRN_CTRLT, 1);
-
 	accumulate_time(vcpu, &vcpu->arch.rm_exit);
 
 	/* Advance host PURR/SPURR by the amount used by guest */
@@ -426,6 +427,13 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	switch_mmu_to_host_radix(kvm, host_pidr);
 
+	/*
+	 * If we are in real mode, only switch MMU on after the MMU is
+	 * switched to host, to avoid the P9_RADIX_PREFETCH_BUG.
+	 */
+	__mtmsrd(msr, 0);
+	mtspr(SPRN_CTRLT, 1);
+
 	end_timing(vcpu);
 
 	return trap;
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 6118e8a97ddd..61f71a7df238 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1710,40 +1710,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	eieio
 	tlbsync
 	ptesync
-
-BEGIN_FTR_SECTION
-	/* Radix: Handle the case where the guest used an illegal PID */
-	LOAD_REG_ADDR(r4, mmu_base_pid)
-	lwz	r3, VCPU_GUEST_PID(r9)
-	lwz	r5, 0(r4)
-	cmpw	cr0,r3,r5
-	blt	2f
-
-	/*
-	 * Illegal PID, the HW might have prefetched and cached in the TLB
-	 * some translations for the  LPID 0 / guest PID combination which
-	 * Linux doesn't know about, so we need to flush that PID out of
-	 * the TLB. First we need to set LPIDR to 0 so tlbiel applies to
-	 * the right context.
-	*/
-	li	r0,0
-	mtspr	SPRN_LPID,r0
-	isync
-
-	/* Then do a congruence class local flush */
-	ld	r6,VCPU_KVM(r9)
-	lwz	r0,KVM_TLB_SETS(r6)
-	mtctr	r0
-	li	r7,0x400		/* IS field = 0b01 */
-	ptesync
-	sldi	r0,r3,32		/* RS has PID */
-1:	PPC_TLBIEL(7,0,2,1,1)		/* RIC=2, PRS=1, R=1 */
-	addi	r7,r7,0x1000
-	bdnz	1b
-	ptesync
-END_FTR_SECTION_IFSET(CPU_FTR_P9_RADIX_PREFETCH_BUG)
-
-2:
 #endif /* CONFIG_PPC_RADIX_MMU */
 
 	/*
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 98f0b243c1ab..1ea95891a79e 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -357,30 +357,19 @@ static void __init radix_init_pgtable(void)
 	}
 
 	/* Find out how many PID bits are supported */
-	if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) {
-		if (!mmu_pid_bits)
-			mmu_pid_bits = 20;
-		mmu_base_pid = 1;
-	} else if (cpu_has_feature(CPU_FTR_HVMODE)) {
-		if (!mmu_pid_bits)
-			mmu_pid_bits = 20;
-#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+	if (!cpu_has_feature(CPU_FTR_HVMODE) &&
+			cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) {
 		/*
-		 * When KVM is possible, we only use the top half of the
-		 * PID space to avoid collisions between host and guest PIDs
-		 * which can cause problems due to prefetch when exiting the
-		 * guest with AIL=3
+		 * Older versions of KVM on these machines perfer if the
+		 * guest only uses the low 19 PID bits.
 		 */
-		mmu_base_pid = 1 << (mmu_pid_bits - 1);
-#else
-		mmu_base_pid = 1;
-#endif
-	} else {
-		/* The guest uses the bottom half of the PID space */
 		if (!mmu_pid_bits)
 			mmu_pid_bits = 19;
-		mmu_base_pid = 1;
+	} else {
+		if (!mmu_pid_bits)
+			mmu_pid_bits = 20;
 	}
+	mmu_base_pid = 1;
 
 	/*
 	 * Allocate Partition table and process table for the
diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
index 409e61210789..312236a6b085 100644
--- a/arch/powerpc/mm/book3s64/radix_tlb.c
+++ b/arch/powerpc/mm/book3s64/radix_tlb.c
@@ -1336,49 +1336,3 @@ void radix__flush_tlb_all(void)
 		     : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(0) : "memory");
 	asm volatile("eieio; tlbsync; ptesync": : :"memory");
 }
-
-#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-extern void radix_kvm_prefetch_workaround(struct mm_struct *mm)
-{
-	unsigned long pid = mm->context.id;
-
-	if (unlikely(pid == MMU_NO_CONTEXT))
-		return;
-
-	if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
-		return;
-
-	/*
-	 * If this context hasn't run on that CPU before and KVM is
-	 * around, there's a slim chance that the guest on another
-	 * CPU just brought in obsolete translation into the TLB of
-	 * this CPU due to a bad prefetch using the guest PID on
-	 * the way into the hypervisor.
-	 *
-	 * We work around this here. If KVM is possible, we check if
-	 * any sibling thread is in KVM. If it is, the window may exist
-	 * and thus we flush that PID from the core.
-	 *
-	 * A potential future improvement would be to mark which PIDs
-	 * have never been used on the system and avoid it if the PID
-	 * is new and the process has no other cpumask bit set.
-	 */
-	if (cpu_has_feature(CPU_FTR_HVMODE) && radix_enabled()) {
-		int cpu = smp_processor_id();
-		int sib = cpu_first_thread_sibling(cpu);
-		bool flush = false;
-
-		for (; sib <= cpu_last_thread_sibling(cpu) && !flush; sib++) {
-			if (sib == cpu)
-				continue;
-			if (!cpu_possible(sib))
-				continue;
-			if (paca_ptrs[sib]->kvm_hstate.kvm_vcpu)
-				flush = true;
-		}
-		if (flush)
-			_tlbiel_pid(pid, RIC_FLUSH_ALL);
-	}
-}
-EXPORT_SYMBOL_GPL(radix_kvm_prefetch_workaround);
-#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
diff --git a/arch/powerpc/mm/mmu_context.c b/arch/powerpc/mm/mmu_context.c
index 18f20da0d348..7479d39976c9 100644
--- a/arch/powerpc/mm/mmu_context.c
+++ b/arch/powerpc/mm/mmu_context.c
@@ -81,9 +81,7 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 		asm volatile ("dssall");
 
-	if (new_on_cpu)
-		radix_kvm_prefetch_workaround(next);
-	else
+	if (!new_on_cpu)
 		membarrier_arch_switch_mm(prev, next, tsk);
 
 	/*
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 37/46] KVM: PPC: Book3S HV: Remove support for dependent threads mode on P9
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Radix guest support will be removed from the P7/8 path, so disallow
dependent threads mode on P9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/include/asm/kvm_host.h |  1 -
 arch/powerpc/kvm/book3s_hv.c        | 27 +++++----------------------
 2 files changed, 5 insertions(+), 23 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 05fb00d37609..dd017dfa4e65 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -304,7 +304,6 @@ struct kvm_arch {
 	u8 fwnmi_enabled;
 	u8 secure_guest;
 	u8 svm_enabled;
-	bool threads_indep;
 	bool nested_enable;
 	bool dawr1_enabled;
 	pgd_t *pgtable;
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 8480cbe4b4fa..85a14ce0ea0e 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -103,13 +103,9 @@ static int target_smt_mode;
 module_param(target_smt_mode, int, 0644);
 MODULE_PARM_DESC(target_smt_mode, "Target threads per core (0 = max)");
 
-static bool indep_threads_mode = true;
-module_param(indep_threads_mode, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(indep_threads_mode, "Independent-threads mode (only on POWER9)");
-
 static bool one_vm_per_core;
 module_param(one_vm_per_core, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(one_vm_per_core, "Only run vCPUs from the same VM on a core (requires indep_threads_mode=N)");
+MODULE_PARM_DESC(one_vm_per_core, "Only run vCPUs from the same VM on a core (requires POWER8 or older)");
 
 #ifdef CONFIG_KVM_XICS
 static const struct kernel_param_ops module_param_ops = {
@@ -2247,7 +2243,7 @@ static int kvmppc_set_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,
  */
 static int threads_per_vcore(struct kvm *kvm)
 {
-	if (kvm->arch.threads_indep)
+	if (cpu_has_feature(CPU_FTR_ARCH_300))
 		return 1;
 	return threads_per_subcore;
 }
@@ -4345,7 +4341,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
 	vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
 
 	do {
-		if (kvm->arch.threads_indep && kvm_is_radix(kvm))
+		if (kvm_is_radix(kvm))
 			r = kvmhv_run_single_vcpu(vcpu, ~(u64)0,
 						  vcpu->arch.vcore->lpcr);
 		else
@@ -4961,21 +4957,8 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm)
 	/*
 	 * Track that we now have a HV mode VM active. This blocks secondary
 	 * CPU threads from coming online.
-	 * On POWER9, we only need to do this if the "indep_threads_mode"
-	 * module parameter has been set to N.
 	 */
-	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
-		if (!indep_threads_mode && !cpu_has_feature(CPU_FTR_HVMODE)) {
-			pr_warn("KVM: Ignoring indep_threads_mode=N in nested hypervisor\n");
-			kvm->arch.threads_indep = true;
-		} else if (!indep_threads_mode && cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) {
-			pr_warn("KVM: Ignoring indep_threads_mode=N on pre-DD2.2 POWER9\n");
-			kvm->arch.threads_indep = true;
-		} else {
-			kvm->arch.threads_indep = indep_threads_mode;
-		}
-	}
-	if (!kvm->arch.threads_indep)
+	if (!cpu_has_feature(CPU_FTR_ARCH_300))
 		kvm_hv_vm_activated();
 
 	/*
@@ -5016,7 +4999,7 @@ static void kvmppc_core_destroy_vm_hv(struct kvm *kvm)
 {
 	debugfs_remove_recursive(kvm->arch.debugfs_dir);
 
-	if (!kvm->arch.threads_indep)
+	if (!cpu_has_feature(CPU_FTR_ARCH_300))
 		kvm_hv_vm_deactivated();
 
 	kvmppc_free_vcores(kvm);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 38/46] KVM: PPC: Book3S HV: Remove radix guest support from P7/8 path
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

The P9 path now runs all supported radix guest combinations, so
remove radix guest support from the P7/8 path.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 79 +------------------------
 1 file changed, 3 insertions(+), 76 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 61f71a7df238..b1f3ee16fd84 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -133,15 +133,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	/* Return the trap number on this thread as the return value */
 	mr	r3, r12
 
-	/*
-	 * If we came back from the guest via a relocation-on interrupt,
-	 * we will be in virtual mode at this point, which makes it a
-	 * little easier to get back to the caller.
-	 */
-	mfmsr	r0
-	andi.	r0, r0, MSR_IR		/* in real mode? */
-	bne	.Lvirt_return
-
 	/* RFI into the highmem handler */
 	mfmsr	r6
 	li	r0, MSR_RI
@@ -151,11 +142,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	mtsrr1	r7
 	RFI_TO_KERNEL
 
-	/* Virtual-mode return */
-.Lvirt_return:
-	mtlr	r8
-	blr
-
 kvmppc_primary_no_guest:
 	/* We handle this much like a ceded vcpu */
 	/* put the HDEC into the DEC, since HDEC interrupts don't wake us */
@@ -899,11 +885,6 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	cmpdi	r3, 512		/* 1 microsecond */
 	blt	hdec_soon
 
-	ld	r6, VCPU_KVM(r4)
-	lbz	r0, KVM_RADIX(r6)
-	cmpwi	r0, 0
-	bne	9f
-
 	/* For hash guest, clear out and reload the SLB */
 BEGIN_MMU_FTR_SECTION
 	/* Radix host won't have populated the SLB, so no need to clear */
@@ -1389,11 +1370,7 @@ guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
 	patch_site 1b patch__call_kvm_flush_link_stack
 
 	/* For hash guest, read the guest SLB and save it away */
-	ld	r5, VCPU_KVM(r9)
-	lbz	r0, KVM_RADIX(r5)
 	li	r5, 0
-	cmpwi	r0, 0
-	bne	0f			/* for radix, save 0 entries */
 	lwz	r0,VCPU_SLB_NR(r9)	/* number of entries in SLB */
 	mtctr	r0
 	li	r6,0
@@ -1432,23 +1409,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
 	slbmte	r6,r5
 1:	addi	r8,r8,16
 	.endr
-	b	guest_bypass
-
-0:	/*
-	 * Malicious or buggy radix guests may have inserted SLB entries
-	 * (only 0..3 because radix always runs with UPRT=1), so these must
-	 * be cleared here to avoid side-channels. slbmte is used rather
-	 * than slbia, as it won't clear cached translations.
-	 */
-	li	r0,0
-	stw	r0,VCPU_SLB_MAX(r9)
-	slbmte	r0,r0
-	li	r4,1
-	slbmte	r0,r4
-	li	r4,2
-	slbmte	r0,r4
-	li	r4,3
-	slbmte	r0,r4
 
 guest_bypass:
 	stw	r12, STACK_SLOT_TRAP(r1)
@@ -1694,24 +1654,6 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_PID, r7
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 
-#ifdef CONFIG_PPC_RADIX_MMU
-	/*
-	 * Are we running hash or radix ?
-	 */
-	ld	r5, VCPU_KVM(r9)
-	lbz	r0, KVM_RADIX(r5)
-	cmpwi	cr2, r0, 0
-	beq	cr2, 2f
-
-	/*
-	 * Radix: do eieio; tlbsync; ptesync sequence in case we
-	 * interrupted the guest between a tlbie and a ptesync.
-	 */
-	eieio
-	tlbsync
-	ptesync
-#endif /* CONFIG_PPC_RADIX_MMU */
-
 	/*
 	 * cp_abort is required if the processor supports local copy-paste
 	 * to clear the copy buffer that was under control of the guest.
@@ -1970,8 +1912,6 @@ kvmppc_tm_emul:
  * reflect the HDSI to the guest as a DSI.
  */
 kvmppc_hdsi:
-	ld	r3, VCPU_KVM(r9)
-	lbz	r0, KVM_RADIX(r3)
 	mfspr	r4, SPRN_HDAR
 	mfspr	r6, SPRN_HDSISR
 BEGIN_FTR_SECTION
@@ -1979,8 +1919,6 @@ BEGIN_FTR_SECTION
 	cmpdi	r6, 0x7fff
 	beq	6f
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
-	cmpwi	r0, 0
-	bne	.Lradix_hdsi		/* on radix, just save DAR/DSISR/ASDR */
 	/* HPTE not found fault or protection fault? */
 	andis.	r0, r6, (DSISR_NOHPTE | DSISR_PROTFAULT)@h
 	beq	1f			/* if not, send it to the guest */
@@ -2057,23 +1995,11 @@ fast_interrupt_c_return:
 	stb	r0, HSTATE_IN_GUEST(r13)
 	b	guest_exit_cont
 
-.Lradix_hdsi:
-	std	r4, VCPU_FAULT_DAR(r9)
-	stw	r6, VCPU_FAULT_DSISR(r9)
-.Lradix_hisi:
-	mfspr	r5, SPRN_ASDR
-	std	r5, VCPU_FAULT_GPA(r9)
-	b	guest_exit_cont
-
 /*
  * Similarly for an HISI, reflect it to the guest as an ISI unless
  * it is an HPTE not found fault for a page that we have paged out.
  */
 kvmppc_hisi:
-	ld	r3, VCPU_KVM(r9)
-	lbz	r0, KVM_RADIX(r3)
-	cmpwi	r0, 0
-	bne	.Lradix_hisi		/* for radix, just save ASDR */
 	andis.	r0, r11, SRR1_ISI_NOPT@h
 	beq	1f
 	andi.	r0, r11, MSR_IR		/* instruction relocation enabled? */
@@ -3217,15 +3143,16 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_DAWRX1, r0
 END_FTR_SECTION_IFSET(CPU_FTR_DAWR1)
 
-	/* Clear hash and radix guest SLB. */
+	/* Clear guest SLB. */
 	slbmte	r0, r0
 	PPC_SLBIA(6)
+	ptesync
 
 BEGIN_MMU_FTR_SECTION
 	b	4f
 END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
 
-	ptesync
+	/* load host SLB entries */
 	ld	r8, PACA_SLBSHADOWPTR(r13)
 	.rept	SLB_NUM_BOLTED
 	li	r3, SLBSHADOW_SAVEAREA
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 39/46] KVM: PPC: Book3S HV: Remove virt mode checks from real mode handlers
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Cédric Le Goater, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Now that the P7/8 path no longer supports radix, real-mode handlers
do not need to deal with being called in virt mode.

This change effectively reverts commit acde25726bc6 ("KVM: PPC: Book3S
HV: Add radix checks in real-mode hypercall handlers").

It removes a few more real-mode tests in rm hcall handlers, which also
allows the indirect ops for the xive module to be removed from the
built-in xics rm handlers.

kvmppc_h_random is renamed to kvmppc_rm_h_random to be a bit more
descriptive of its function.

Cc: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/include/asm/kvm_ppc.h      | 10 +--
 arch/powerpc/kvm/book3s.c               | 11 +--
 arch/powerpc/kvm/book3s_64_vio_hv.c     | 12 ----
 arch/powerpc/kvm/book3s_hv_builtin.c    | 91 ++++++-------------------
 arch/powerpc/kvm/book3s_hv_rmhandlers.S |  2 +-
 arch/powerpc/kvm/book3s_xive.c          | 18 -----
 arch/powerpc/kvm/book3s_xive.h          |  7 --
 arch/powerpc/kvm/book3s_xive_native.c   | 10 ---
 8 files changed, 23 insertions(+), 138 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index db6646c2ade2..5dfb3f167f2c 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -659,8 +659,6 @@ extern int kvmppc_xive_get_xive(struct kvm *kvm, u32 irq, u32 *server,
 				u32 *priority);
 extern int kvmppc_xive_int_on(struct kvm *kvm, u32 irq);
 extern int kvmppc_xive_int_off(struct kvm *kvm, u32 irq);
-extern void kvmppc_xive_init_module(void);
-extern void kvmppc_xive_exit_module(void);
 
 extern int kvmppc_xive_connect_vcpu(struct kvm_device *dev,
 				    struct kvm_vcpu *vcpu, u32 cpu);
@@ -686,8 +684,6 @@ static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
 extern int kvmppc_xive_native_connect_vcpu(struct kvm_device *dev,
 					   struct kvm_vcpu *vcpu, u32 cpu);
 extern void kvmppc_xive_native_cleanup_vcpu(struct kvm_vcpu *vcpu);
-extern void kvmppc_xive_native_init_module(void);
-extern void kvmppc_xive_native_exit_module(void);
 extern int kvmppc_xive_native_get_vp(struct kvm_vcpu *vcpu,
 				     union kvmppc_one_reg *val);
 extern int kvmppc_xive_native_set_vp(struct kvm_vcpu *vcpu,
@@ -701,8 +697,6 @@ static inline int kvmppc_xive_get_xive(struct kvm *kvm, u32 irq, u32 *server,
 				       u32 *priority) { return -1; }
 static inline int kvmppc_xive_int_on(struct kvm *kvm, u32 irq) { return -1; }
 static inline int kvmppc_xive_int_off(struct kvm *kvm, u32 irq) { return -1; }
-static inline void kvmppc_xive_init_module(void) { }
-static inline void kvmppc_xive_exit_module(void) { }
 
 static inline int kvmppc_xive_connect_vcpu(struct kvm_device *dev,
 					   struct kvm_vcpu *vcpu, u32 cpu) { return -EBUSY; }
@@ -725,8 +719,6 @@ static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu)
 static inline int kvmppc_xive_native_connect_vcpu(struct kvm_device *dev,
 			  struct kvm_vcpu *vcpu, u32 cpu) { return -EBUSY; }
 static inline void kvmppc_xive_native_cleanup_vcpu(struct kvm_vcpu *vcpu) { }
-static inline void kvmppc_xive_native_init_module(void) { }
-static inline void kvmppc_xive_native_exit_module(void) { }
 static inline int kvmppc_xive_native_get_vp(struct kvm_vcpu *vcpu,
 					    union kvmppc_one_reg *val)
 { return 0; }
@@ -762,7 +754,7 @@ long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
 			   unsigned long tce_value, unsigned long npages);
 long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target,
                             unsigned int yield_count);
-long kvmppc_h_random(struct kvm_vcpu *vcpu);
+long kvmppc_rm_h_random(struct kvm_vcpu *vcpu);
 void kvmhv_commence_exit(int trap);
 void kvmppc_realmode_machine_check(struct kvm_vcpu *vcpu);
 void kvmppc_subcore_enter_guest(void);
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 44bf567b6589..1888aedfd410 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -1046,13 +1046,10 @@ static int kvmppc_book3s_init(void)
 #ifdef CONFIG_KVM_XICS
 #ifdef CONFIG_KVM_XIVE
 	if (xics_on_xive()) {
-		kvmppc_xive_init_module();
 		kvm_register_device_ops(&kvm_xive_ops, KVM_DEV_TYPE_XICS);
-		if (kvmppc_xive_native_supported()) {
-			kvmppc_xive_native_init_module();
+		if (kvmppc_xive_native_supported())
 			kvm_register_device_ops(&kvm_xive_native_ops,
 						KVM_DEV_TYPE_XIVE);
-		}
 	} else
 #endif
 		kvm_register_device_ops(&kvm_xics_ops, KVM_DEV_TYPE_XICS);
@@ -1062,12 +1059,6 @@ static int kvmppc_book3s_init(void)
 
 static void kvmppc_book3s_exit(void)
 {
-#ifdef CONFIG_KVM_XICS
-	if (xics_on_xive()) {
-		kvmppc_xive_exit_module();
-		kvmppc_xive_native_exit_module();
-	}
-#endif
 #ifdef CONFIG_KVM_BOOK3S_32_HANDLER
 	kvmppc_book3s_exit_pr();
 #endif
diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c
index 083a4e037718..dc6591548f0c 100644
--- a/arch/powerpc/kvm/book3s_64_vio_hv.c
+++ b/arch/powerpc/kvm/book3s_64_vio_hv.c
@@ -391,10 +391,6 @@ long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
 	/* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
 	/* 	    liobn, ioba, tce); */
 
-	/* For radix, we might be in virtual mode, so punt */
-	if (kvm_is_radix(vcpu->kvm))
-		return H_TOO_HARD;
-
 	stt = kvmppc_find_table(vcpu->kvm, liobn);
 	if (!stt)
 		return H_TOO_HARD;
@@ -489,10 +485,6 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
 	bool prereg = false;
 	struct kvmppc_spapr_tce_iommu_table *stit;
 
-	/* For radix, we might be in virtual mode, so punt */
-	if (kvm_is_radix(vcpu->kvm))
-		return H_TOO_HARD;
-
 	/*
 	 * used to check for invalidations in progress
 	 */
@@ -602,10 +594,6 @@ long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
 	long i, ret;
 	struct kvmppc_spapr_tce_iommu_table *stit;
 
-	/* For radix, we might be in virtual mode, so punt */
-	if (kvm_is_radix(vcpu->kvm))
-		return H_TOO_HARD;
-
 	stt = kvmppc_find_table(vcpu->kvm, liobn);
 	if (!stt)
 		return H_TOO_HARD;
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 7a0e33a9c980..8d669a0e15f8 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -34,21 +34,6 @@
 #include "book3s_xics.h"
 #include "book3s_xive.h"
 
-/*
- * The XIVE module will populate these when it loads
- */
-unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
-unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
-int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
-		       unsigned long mfrr);
-int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
-int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
-EXPORT_SYMBOL_GPL(__xive_vm_h_xirr);
-EXPORT_SYMBOL_GPL(__xive_vm_h_ipoll);
-EXPORT_SYMBOL_GPL(__xive_vm_h_ipi);
-EXPORT_SYMBOL_GPL(__xive_vm_h_cppr);
-EXPORT_SYMBOL_GPL(__xive_vm_h_eoi);
-
 /*
  * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
  * should be power of 2.
@@ -196,16 +181,9 @@ int kvmppc_hwrng_present(void)
 }
 EXPORT_SYMBOL_GPL(kvmppc_hwrng_present);
 
-long kvmppc_h_random(struct kvm_vcpu *vcpu)
+long kvmppc_rm_h_random(struct kvm_vcpu *vcpu)
 {
-	int r;
-
-	/* Only need to do the expensive mfmsr() on radix */
-	if (kvm_is_radix(vcpu->kvm) && (mfmsr() & MSR_IR))
-		r = powernv_get_random_long(&vcpu->arch.regs.gpr[4]);
-	else
-		r = powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]);
-	if (r)
+	if (powernv_get_random_real_mode(&vcpu->arch.regs.gpr[4]))
 		return H_SUCCESS;
 
 	return H_HARDWARE;
@@ -541,22 +519,13 @@ static long kvmppc_read_one_intr(bool *again)
 }
 
 #ifdef CONFIG_KVM_XICS
-static inline bool is_rm(void)
-{
-	return !(mfmsr() & MSR_DR);
-}
-
 unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu)
 {
 	if (!kvmppc_xics_enabled(vcpu))
 		return H_TOO_HARD;
-	if (xics_on_xive()) {
-		if (is_rm())
-			return xive_rm_h_xirr(vcpu);
-		if (unlikely(!__xive_vm_h_xirr))
-			return H_NOT_AVAILABLE;
-		return __xive_vm_h_xirr(vcpu);
-	} else
+	if (xics_on_xive())
+		return xive_rm_h_xirr(vcpu);
+	else
 		return xics_rm_h_xirr(vcpu);
 }
 
@@ -565,13 +534,9 @@ unsigned long kvmppc_rm_h_xirr_x(struct kvm_vcpu *vcpu)
 	if (!kvmppc_xics_enabled(vcpu))
 		return H_TOO_HARD;
 	vcpu->arch.regs.gpr[5] = get_tb();
-	if (xics_on_xive()) {
-		if (is_rm())
-			return xive_rm_h_xirr(vcpu);
-		if (unlikely(!__xive_vm_h_xirr))
-			return H_NOT_AVAILABLE;
-		return __xive_vm_h_xirr(vcpu);
-	} else
+	if (xics_on_xive())
+		return xive_rm_h_xirr(vcpu);
+	else
 		return xics_rm_h_xirr(vcpu);
 }
 
@@ -579,13 +544,9 @@ unsigned long kvmppc_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server)
 {
 	if (!kvmppc_xics_enabled(vcpu))
 		return H_TOO_HARD;
-	if (xics_on_xive()) {
-		if (is_rm())
-			return xive_rm_h_ipoll(vcpu, server);
-		if (unlikely(!__xive_vm_h_ipoll))
-			return H_NOT_AVAILABLE;
-		return __xive_vm_h_ipoll(vcpu, server);
-	} else
+	if (xics_on_xive())
+		return xive_rm_h_ipoll(vcpu, server);
+	else
 		return H_TOO_HARD;
 }
 
@@ -594,13 +555,9 @@ int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
 {
 	if (!kvmppc_xics_enabled(vcpu))
 		return H_TOO_HARD;
-	if (xics_on_xive()) {
-		if (is_rm())
-			return xive_rm_h_ipi(vcpu, server, mfrr);
-		if (unlikely(!__xive_vm_h_ipi))
-			return H_NOT_AVAILABLE;
-		return __xive_vm_h_ipi(vcpu, server, mfrr);
-	} else
+	if (xics_on_xive())
+		return xive_rm_h_ipi(vcpu, server, mfrr);
+	else
 		return xics_rm_h_ipi(vcpu, server, mfrr);
 }
 
@@ -608,13 +565,9 @@ int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
 {
 	if (!kvmppc_xics_enabled(vcpu))
 		return H_TOO_HARD;
-	if (xics_on_xive()) {
-		if (is_rm())
-			return xive_rm_h_cppr(vcpu, cppr);
-		if (unlikely(!__xive_vm_h_cppr))
-			return H_NOT_AVAILABLE;
-		return __xive_vm_h_cppr(vcpu, cppr);
-	} else
+	if (xics_on_xive())
+		return xive_rm_h_cppr(vcpu, cppr);
+	else
 		return xics_rm_h_cppr(vcpu, cppr);
 }
 
@@ -622,13 +575,9 @@ int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
 {
 	if (!kvmppc_xics_enabled(vcpu))
 		return H_TOO_HARD;
-	if (xics_on_xive()) {
-		if (is_rm())
-			return xive_rm_h_eoi(vcpu, xirr);
-		if (unlikely(!__xive_vm_h_eoi))
-			return H_NOT_AVAILABLE;
-		return __xive_vm_h_eoi(vcpu, xirr);
-	} else
+	if (xics_on_xive())
+		return xive_rm_h_eoi(vcpu, xirr);
+	else
 		return xics_rm_h_eoi(vcpu, xirr);
 }
 #endif /* CONFIG_KVM_XICS */
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index b1f3ee16fd84..564ca9feef35 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -2323,7 +2323,7 @@ hcall_real_table:
 #else
 	.long	0		/* 0x2fc - H_XIRR_X*/
 #endif
-	.long	DOTSYM(kvmppc_h_random) - hcall_real_table
+	.long	DOTSYM(kvmppc_rm_h_random) - hcall_real_table
 	.globl	hcall_real_table_end
 hcall_real_table_end:
 
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
index dcc07ceaf5ca..80d32b4eb898 100644
--- a/arch/powerpc/kvm/book3s_xive.c
+++ b/arch/powerpc/kvm/book3s_xive.c
@@ -2358,21 +2358,3 @@ struct kvm_device_ops kvm_xive_ops = {
 	.get_attr = xive_get_attr,
 	.has_attr = xive_has_attr,
 };
-
-void kvmppc_xive_init_module(void)
-{
-	__xive_vm_h_xirr = xive_vm_h_xirr;
-	__xive_vm_h_ipoll = xive_vm_h_ipoll;
-	__xive_vm_h_ipi = xive_vm_h_ipi;
-	__xive_vm_h_cppr = xive_vm_h_cppr;
-	__xive_vm_h_eoi = xive_vm_h_eoi;
-}
-
-void kvmppc_xive_exit_module(void)
-{
-	__xive_vm_h_xirr = NULL;
-	__xive_vm_h_ipoll = NULL;
-	__xive_vm_h_ipi = NULL;
-	__xive_vm_h_cppr = NULL;
-	__xive_vm_h_eoi = NULL;
-}
diff --git a/arch/powerpc/kvm/book3s_xive.h b/arch/powerpc/kvm/book3s_xive.h
index 86c24a4ad809..afe9eeac6d56 100644
--- a/arch/powerpc/kvm/book3s_xive.h
+++ b/arch/powerpc/kvm/book3s_xive.h
@@ -289,13 +289,6 @@ extern int xive_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
 extern int xive_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr);
 extern int xive_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr);
 
-extern unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
-extern unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
-extern int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
-			      unsigned long mfrr);
-extern int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
-extern int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
-
 /*
  * Common Xive routines for XICS-over-XIVE and XIVE native
  */
diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c
index 76800c84f2a3..1253666dd4d8 100644
--- a/arch/powerpc/kvm/book3s_xive_native.c
+++ b/arch/powerpc/kvm/book3s_xive_native.c
@@ -1281,13 +1281,3 @@ struct kvm_device_ops kvm_xive_native_ops = {
 	.has_attr = kvmppc_xive_native_has_attr,
 	.mmap = kvmppc_xive_native_mmap,
 };
-
-void kvmppc_xive_native_init_module(void)
-{
-	;
-}
-
-void kvmppc_xive_native_exit_module(void)
-{
-	;
-}
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 40/46] KVM: PPC: Book3S HV: Remove unused nested HV tests in XICS emulation
From: Nicholas Piggin @ 2021-03-23  1:02 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Cédric Le Goater, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Commit f3c18e9342a44 ("KVM: PPC: Book3S HV: Use XICS hypercalls when
running as a nested hypervisor") added nested HV tests in XICS
hypercalls, but not all are required.

* icp_eoi is only called by kvmppc_deliver_irq_passthru which is only
  called by kvmppc_check_passthru which is only caled by
  kvmppc_read_one_intr.

* kvmppc_read_one_intr is only called by kvmppc_read_intr which is only
  called by the L0 HV rmhandlers code.

* kvmhv_rm_send_ipi is called by:
  - kvmhv_interrupt_vcore which is only called by kvmhv_commence_exit
    which is only called by the L0 HV rmhandlers code.
  - icp_send_hcore_msg which is only called by icp_rm_set_vcpu_irq.
  - icp_rm_set_vcpu_irq which is only called by icp_rm_try_update
  - icp_rm_set_vcpu_irq is not nested HV safe because it writes to
    LPCR directly without a kvmhv_on_pseries test. Nested handlers
    should not in general be using the rm handlers.

The important test seems to be in kvmppc_ipi_thread, which sends the
virt-mode H_IPI handler kick to use smp_call_function rather than
msgsnd.

Cc: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv_builtin.c | 44 +++++-----------------------
 arch/powerpc/kvm/book3s_hv_rm_xics.c | 15 ----------
 2 files changed, 8 insertions(+), 51 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 8d669a0e15f8..259492bb4153 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -199,15 +199,6 @@ void kvmhv_rm_send_ipi(int cpu)
 	void __iomem *xics_phys;
 	unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
 
-	/* For a nested hypervisor, use the XICS via hcall */
-	if (kvmhv_on_pseries()) {
-		unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
-
-		plpar_hcall_raw(H_IPI, retbuf, get_hard_smp_processor_id(cpu),
-				IPI_PRIORITY);
-		return;
-	}
-
 	/* On POWER9 we can use msgsnd for any destination cpu. */
 	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
 		msg |= get_hard_smp_processor_id(cpu);
@@ -420,19 +411,12 @@ static long kvmppc_read_one_intr(bool *again)
 		return 1;
 
 	/* Now read the interrupt from the ICP */
-	if (kvmhv_on_pseries()) {
-		unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
-
-		rc = plpar_hcall_raw(H_XIRR, retbuf, 0xFF);
-		xirr = cpu_to_be32(retbuf[0]);
-	} else {
-		xics_phys = local_paca->kvm_hstate.xics_phys;
-		rc = 0;
-		if (!xics_phys)
-			rc = opal_int_get_xirr(&xirr, false);
-		else
-			xirr = __raw_rm_readl(xics_phys + XICS_XIRR);
-	}
+	xics_phys = local_paca->kvm_hstate.xics_phys;
+	rc = 0;
+	if (!xics_phys)
+		rc = opal_int_get_xirr(&xirr, false);
+	else
+		xirr = __raw_rm_readl(xics_phys + XICS_XIRR);
 	if (rc < 0)
 		return 1;
 
@@ -461,13 +445,7 @@ static long kvmppc_read_one_intr(bool *again)
 	 */
 	if (xisr == XICS_IPI) {
 		rc = 0;
-		if (kvmhv_on_pseries()) {
-			unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
-
-			plpar_hcall_raw(H_IPI, retbuf,
-					hard_smp_processor_id(), 0xff);
-			plpar_hcall_raw(H_EOI, retbuf, h_xirr);
-		} else if (xics_phys) {
+		if (xics_phys) {
 			__raw_rm_writeb(0xff, xics_phys + XICS_MFRR);
 			__raw_rm_writel(xirr, xics_phys + XICS_XIRR);
 		} else {
@@ -493,13 +471,7 @@ static long kvmppc_read_one_intr(bool *again)
 			/* We raced with the host,
 			 * we need to resend that IPI, bummer
 			 */
-			if (kvmhv_on_pseries()) {
-				unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
-
-				plpar_hcall_raw(H_IPI, retbuf,
-						hard_smp_processor_id(),
-						IPI_PRIORITY);
-			} else if (xics_phys)
+			if (xics_phys)
 				__raw_rm_writeb(IPI_PRIORITY,
 						xics_phys + XICS_MFRR);
 			else
diff --git a/arch/powerpc/kvm/book3s_hv_rm_xics.c b/arch/powerpc/kvm/book3s_hv_rm_xics.c
index c2c9c733f359..0a11ec88a0ae 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_xics.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_xics.c
@@ -141,13 +141,6 @@ static void icp_rm_set_vcpu_irq(struct kvm_vcpu *vcpu,
 		return;
 	}
 
-	if (xive_enabled() && kvmhv_on_pseries()) {
-		/* No XICS access or hypercalls available, too hard */
-		this_icp->rm_action |= XICS_RM_KICK_VCPU;
-		this_icp->rm_kick_target = vcpu;
-		return;
-	}
-
 	/*
 	 * Check if the core is loaded,
 	 * if not, find an available host core to post to wake the VCPU,
@@ -771,14 +764,6 @@ static void icp_eoi(struct irq_chip *c, u32 hwirq, __be32 xirr, bool *again)
 	void __iomem *xics_phys;
 	int64_t rc;
 
-	if (kvmhv_on_pseries()) {
-		unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
-
-		iosync();
-		plpar_hcall_raw(H_EOI, retbuf, hwirq);
-		return;
-	}
-
 	rc = pnv_opal_pci_msi_eoi(c, hwirq);
 
 	if (rc)
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 41/46] KVM: PPC: Book3S HV P9: Allow all P9 processors to enable nested HV
From: Nicholas Piggin @ 2021-03-23  1:03 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

All radix guests go via the P9 path now, so there is no need to limit
nested HV to processors that support "mixed mode" MMU. Remove the
restriction.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 85a14ce0ea0e..0f3c1792ab86 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -5420,7 +5420,7 @@ static int kvmhv_enable_nested(struct kvm *kvm)
 {
 	if (!nested)
 		return -EPERM;
-	if (!cpu_has_feature(CPU_FTR_ARCH_300) || no_mixing_hpt_and_radix)
+	if (!cpu_has_feature(CPU_FTR_ARCH_300))
 		return -ENODEV;
 
 	/* kvm == NULL means the caller is testing if the capability exists */
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 42/46] KVM: PPC: Book3S HV: small pseries_do_hcall cleanup
From: Nicholas Piggin @ 2021-03-23  1:03 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Functionality should not be changed.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 0f3c1792ab86..e6d113dbc076 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -925,6 +925,7 @@ static int kvmppc_get_yield_count(struct kvm_vcpu *vcpu)
 
 int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 {
+	struct kvm *kvm = vcpu->kvm;
 	unsigned long req = kvmppc_get_gpr(vcpu, 3);
 	unsigned long target, ret = H_SUCCESS;
 	int yield_count;
@@ -940,7 +941,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 		break;
 	case H_PROD:
 		target = kvmppc_get_gpr(vcpu, 4);
-		tvcpu = kvmppc_find_vcpu(vcpu->kvm, target);
+		tvcpu = kvmppc_find_vcpu(kvm, target);
 		if (!tvcpu) {
 			ret = H_PARAMETER;
 			break;
@@ -954,7 +955,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 		target = kvmppc_get_gpr(vcpu, 4);
 		if (target == -1)
 			break;
-		tvcpu = kvmppc_find_vcpu(vcpu->kvm, target);
+		tvcpu = kvmppc_find_vcpu(kvm, target);
 		if (!tvcpu) {
 			ret = H_PARAMETER;
 			break;
@@ -970,12 +971,12 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 					kvmppc_get_gpr(vcpu, 6));
 		break;
 	case H_RTAS:
-		if (list_empty(&vcpu->kvm->arch.rtas_tokens))
+		if (list_empty(&kvm->arch.rtas_tokens))
 			return RESUME_HOST;
 
-		idx = srcu_read_lock(&vcpu->kvm->srcu);
+		idx = srcu_read_lock(&kvm->srcu);
 		rc = kvmppc_rtas_hcall(vcpu);
-		srcu_read_unlock(&vcpu->kvm->srcu, idx);
+		srcu_read_unlock(&kvm->srcu, idx);
 
 		if (rc == -ENOENT)
 			return RESUME_HOST;
@@ -1062,12 +1063,12 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 
 	case H_SET_PARTITION_TABLE:
 		ret = H_FUNCTION;
-		if (nesting_enabled(vcpu->kvm))
+		if (nesting_enabled(kvm))
 			ret = kvmhv_set_partition_table(vcpu);
 		break;
 	case H_ENTER_NESTED:
 		ret = H_FUNCTION;
-		if (!nesting_enabled(vcpu->kvm))
+		if (!nesting_enabled(kvm))
 			break;
 		ret = kvmhv_enter_nested_guest(vcpu);
 		if (ret == H_INTERRUPT) {
@@ -1082,12 +1083,12 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 		break;
 	case H_TLB_INVALIDATE:
 		ret = H_FUNCTION;
-		if (nesting_enabled(vcpu->kvm))
+		if (nesting_enabled(kvm))
 			ret = kvmhv_do_nested_tlbie(vcpu);
 		break;
 	case H_COPY_TOFROM_GUEST:
 		ret = H_FUNCTION;
-		if (nesting_enabled(vcpu->kvm))
+		if (nesting_enabled(kvm))
 			ret = kvmhv_copy_tofrom_guest_nested(vcpu);
 		break;
 	case H_PAGE_INIT:
@@ -1098,7 +1099,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 	case H_SVM_PAGE_IN:
 		ret = H_UNSUPPORTED;
 		if (kvmppc_get_srr1(vcpu) & MSR_S)
-			ret = kvmppc_h_svm_page_in(vcpu->kvm,
+			ret = kvmppc_h_svm_page_in(kvm,
 						   kvmppc_get_gpr(vcpu, 4),
 						   kvmppc_get_gpr(vcpu, 5),
 						   kvmppc_get_gpr(vcpu, 6));
@@ -1106,7 +1107,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 	case H_SVM_PAGE_OUT:
 		ret = H_UNSUPPORTED;
 		if (kvmppc_get_srr1(vcpu) & MSR_S)
-			ret = kvmppc_h_svm_page_out(vcpu->kvm,
+			ret = kvmppc_h_svm_page_out(kvm,
 						    kvmppc_get_gpr(vcpu, 4),
 						    kvmppc_get_gpr(vcpu, 5),
 						    kvmppc_get_gpr(vcpu, 6));
@@ -1114,12 +1115,12 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 	case H_SVM_INIT_START:
 		ret = H_UNSUPPORTED;
 		if (kvmppc_get_srr1(vcpu) & MSR_S)
-			ret = kvmppc_h_svm_init_start(vcpu->kvm);
+			ret = kvmppc_h_svm_init_start(kvm);
 		break;
 	case H_SVM_INIT_DONE:
 		ret = H_UNSUPPORTED;
 		if (kvmppc_get_srr1(vcpu) & MSR_S)
-			ret = kvmppc_h_svm_init_done(vcpu->kvm);
+			ret = kvmppc_h_svm_init_done(kvm);
 		break;
 	case H_SVM_INIT_ABORT:
 		/*
@@ -1129,7 +1130,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 		 * Instead the kvm->arch.secure_guest flag is checked inside
 		 * kvmppc_h_svm_init_abort().
 		 */
-		ret = kvmppc_h_svm_init_abort(vcpu->kvm);
+		ret = kvmppc_h_svm_init_abort(kvm);
 		break;
 
 	default:
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 43/46] KVM: PPC: Book3S HV: add virtual mode handlers for HPT hcalls and page faults
From: Nicholas Piggin @ 2021-03-23  1:03 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

In order to support hash guests in the P9 path (which does not do real
mode hcalls or page fault handling), these real-mode hash specific
interrupts need to be implemented in virt mode.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c        | 126 ++++++++++++++++++++++++++--
 arch/powerpc/kvm/book3s_hv_rm_mmu.c |   8 ++
 2 files changed, 127 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index e6d113dbc076..5b3b6842d6b9 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -937,6 +937,52 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 		return RESUME_HOST;
 
 	switch (req) {
+	case H_REMOVE:
+		ret = kvmppc_h_remove(vcpu, kvmppc_get_gpr(vcpu, 4),
+					kvmppc_get_gpr(vcpu, 5),
+					kvmppc_get_gpr(vcpu, 6));
+		if (ret == H_TOO_HARD)
+			return RESUME_HOST;
+		break;
+	case H_ENTER:
+		ret = kvmppc_h_enter(vcpu, kvmppc_get_gpr(vcpu, 4),
+					kvmppc_get_gpr(vcpu, 5),
+					kvmppc_get_gpr(vcpu, 6),
+					kvmppc_get_gpr(vcpu, 7));
+		if (ret == H_TOO_HARD)
+			return RESUME_HOST;
+		break;
+	case H_READ:
+		ret = kvmppc_h_read(vcpu, kvmppc_get_gpr(vcpu, 4),
+					kvmppc_get_gpr(vcpu, 5));
+		if (ret == H_TOO_HARD)
+			return RESUME_HOST;
+		break;
+	case H_CLEAR_MOD:
+		ret = kvmppc_h_clear_mod(vcpu, kvmppc_get_gpr(vcpu, 4),
+					kvmppc_get_gpr(vcpu, 5));
+		if (ret == H_TOO_HARD)
+			return RESUME_HOST;
+		break;
+	case H_CLEAR_REF:
+		ret = kvmppc_h_clear_ref(vcpu, kvmppc_get_gpr(vcpu, 4),
+					kvmppc_get_gpr(vcpu, 5));
+		if (ret == H_TOO_HARD)
+			return RESUME_HOST;
+		break;
+	case H_PROTECT:
+		ret = kvmppc_h_protect(vcpu, kvmppc_get_gpr(vcpu, 4),
+					kvmppc_get_gpr(vcpu, 5),
+					kvmppc_get_gpr(vcpu, 6));
+		if (ret == H_TOO_HARD)
+			return RESUME_HOST;
+		break;
+	case H_BULK_REMOVE:
+		ret = kvmppc_h_bulk_remove(vcpu);
+		if (ret == H_TOO_HARD)
+			return RESUME_HOST;
+		break;
+
 	case H_CEDE:
 		break;
 	case H_PROD:
@@ -1136,6 +1182,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 	default:
 		return RESUME_HOST;
 	}
+	WARN_ON_ONCE(ret == H_TOO_HARD);
 	kvmppc_set_gpr(vcpu, 3, ret);
 	vcpu->arch.hcall_needed = 0;
 	return RESUME_GUEST;
@@ -1429,19 +1476,84 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
 	 * host page has been paged out.  Any other HDSI/HISI interrupts
 	 * have been handled already.
 	 */
-	case BOOK3S_INTERRUPT_H_DATA_STORAGE:
-		r = RESUME_PAGE_FAULT;
-		if (vcpu->arch.fault_dsisr == HDSISR_CANARY)
+	case BOOK3S_INTERRUPT_H_DATA_STORAGE: {
+		unsigned long vsid;
+		long err;
+
+		if (vcpu->arch.fault_dsisr == HDSISR_CANARY) {
 			r = RESUME_GUEST; /* Just retry if it's the canary */
+			break;
+		}
+
+		if (kvm_is_radix(vcpu->kvm)) {
+			r = RESUME_PAGE_FAULT;
+			break;
+		}
+
+		if (!(vcpu->arch.fault_dsisr & (DSISR_NOHPTE | DSISR_PROTFAULT))) {
+			kvmppc_core_queue_data_storage(vcpu,
+				vcpu->arch.fault_dar, vcpu->arch.fault_dsisr);
+			r = RESUME_GUEST;
+			break;
+		}
+
+		if (!(vcpu->arch.shregs.msr & MSR_DR))
+			vsid = vcpu->kvm->arch.vrma_slb_v;
+		else
+			vsid = vcpu->arch.fault_gpa;
+
+		err = kvmppc_hpte_hv_fault(vcpu, vcpu->arch.fault_dar,
+				vsid, vcpu->arch.fault_dsisr, true);
+		if (err == 0) {
+			r = RESUME_GUEST;
+		} else if (err == -1 || err == -2) {
+			r = RESUME_PAGE_FAULT;
+		} else {
+			kvmppc_core_queue_data_storage(vcpu,
+				vcpu->arch.fault_dar, err);
+			r = RESUME_GUEST;
+		}
 		break;
-	case BOOK3S_INTERRUPT_H_INST_STORAGE:
+	}
+	case BOOK3S_INTERRUPT_H_INST_STORAGE: {
+		unsigned long vsid;
+		long err;
+
 		vcpu->arch.fault_dar = kvmppc_get_pc(vcpu);
 		vcpu->arch.fault_dsisr = vcpu->arch.shregs.msr &
 			DSISR_SRR1_MATCH_64S;
-		if (vcpu->arch.shregs.msr & HSRR1_HISI_WRITE)
-			vcpu->arch.fault_dsisr |= DSISR_ISSTORE;
-		r = RESUME_PAGE_FAULT;
+		if (kvm_is_radix(vcpu->kvm)) {
+			if (vcpu->arch.shregs.msr & HSRR1_HISI_WRITE)
+				vcpu->arch.fault_dsisr |= DSISR_ISSTORE;
+			r = RESUME_PAGE_FAULT;
+			break;
+		}
+
+		if (!(vcpu->arch.fault_dsisr & SRR1_ISI_NOPT)) {
+			kvmppc_core_queue_inst_storage(vcpu,
+				vcpu->arch.fault_dsisr);
+			r = RESUME_GUEST;
+			break;
+		}
+
+		if (!(vcpu->arch.shregs.msr & MSR_DR))
+			vsid = vcpu->kvm->arch.vrma_slb_v;
+		else
+			vsid = vcpu->arch.fault_gpa;
+
+		err = kvmppc_hpte_hv_fault(vcpu, vcpu->arch.fault_dar,
+				vsid, vcpu->arch.fault_dsisr, false);
+		if (err == 0) {
+			r = RESUME_GUEST;
+		} else if (err == -1) {
+			r = RESUME_PAGE_FAULT;
+		} else {
+			kvmppc_core_queue_inst_storage(vcpu, err);
+			r = RESUME_GUEST;
+		}
 		break;
+	}
+
 	/*
 	 * This occurs if the guest executes an illegal instruction.
 	 * If the guest debug is disabled, generate a program interrupt
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index 7af7c70f1468..8cc73abbf42b 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -409,6 +409,7 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
 				 vcpu->arch.pgdir, true,
 				 &vcpu->arch.regs.gpr[4]);
 }
+EXPORT_SYMBOL_GPL(kvmppc_h_enter);
 
 #ifdef __BIG_ENDIAN__
 #define LOCK_TOKEN	(*(u32 *)(&get_paca()->lock_token))
@@ -553,6 +554,7 @@ long kvmppc_h_remove(struct kvm_vcpu *vcpu, unsigned long flags,
 	return kvmppc_do_h_remove(vcpu->kvm, flags, pte_index, avpn,
 				  &vcpu->arch.regs.gpr[4]);
 }
+EXPORT_SYMBOL_GPL(kvmppc_h_remove);
 
 long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu)
 {
@@ -671,6 +673,7 @@ long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(kvmppc_h_bulk_remove);
 
 long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags,
 		      unsigned long pte_index, unsigned long avpn)
@@ -741,6 +744,7 @@ long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags,
 
 	return H_SUCCESS;
 }
+EXPORT_SYMBOL_GPL(kvmppc_h_protect);
 
 long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags,
 		   unsigned long pte_index)
@@ -781,6 +785,7 @@ long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags,
 	}
 	return H_SUCCESS;
 }
+EXPORT_SYMBOL_GPL(kvmppc_h_read);
 
 long kvmppc_h_clear_ref(struct kvm_vcpu *vcpu, unsigned long flags,
 			unsigned long pte_index)
@@ -829,6 +834,7 @@ long kvmppc_h_clear_ref(struct kvm_vcpu *vcpu, unsigned long flags,
 	unlock_hpte(hpte, v & ~HPTE_V_HVLOCK);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(kvmppc_h_clear_ref);
 
 long kvmppc_h_clear_mod(struct kvm_vcpu *vcpu, unsigned long flags,
 			unsigned long pte_index)
@@ -876,6 +882,7 @@ long kvmppc_h_clear_mod(struct kvm_vcpu *vcpu, unsigned long flags,
 	unlock_hpte(hpte, v & ~HPTE_V_HVLOCK);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(kvmppc_h_clear_mod);
 
 static int kvmppc_get_hpa(struct kvm_vcpu *vcpu, unsigned long mmu_seq,
 			  unsigned long gpa, int writing, unsigned long *hpa,
@@ -1294,3 +1301,4 @@ long kvmppc_hpte_hv_fault(struct kvm_vcpu *vcpu, unsigned long addr,
 
 	return -1;		/* send fault up to host kernel mode */
 }
+EXPORT_SYMBOL_GPL(kvmppc_hpte_hv_fault);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 44/46] KVM: PPC: Book3S HV P9: implement hash guest support
From: Nicholas Piggin @ 2021-03-23  1:03 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

Guest entry/exit has to restore and save/clear the SLB, plus several
other bits to accommodate hash guests in the P9 path.

Radix host, hash guest support is removed from the P7/8 path.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c            |  20 ++-
 arch/powerpc/kvm/book3s_hv_interrupt.c  | 160 ++++++++++++++++--------
 arch/powerpc/kvm/book3s_hv_rm_mmu.c     |   4 +
 arch/powerpc/kvm/book3s_hv_rmhandlers.S |  14 +--
 4 files changed, 131 insertions(+), 67 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 5b3b6842d6b9..c151a60c0daa 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3828,7 +3828,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 		}
 		kvmppc_xive_pull_vcpu(vcpu);
 
-		vcpu->arch.slb_max = 0;
+		if (kvm_is_radix(vcpu->kvm))
+			vcpu->arch.slb_max = 0;
 	}
 
 	dec = mfspr(SPRN_DEC);
@@ -4061,7 +4062,6 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc)
 /*
  * This never fails for a radix guest, as none of the operations it does
  * for a radix guest can fail or have a way to report failure.
- * kvmhv_run_single_vcpu() relies on this fact.
  */
 static int kvmhv_setup_mmu(struct kvm_vcpu *vcpu)
 {
@@ -4240,8 +4240,15 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
 	vc->runner = vcpu;
 
 	/* See if the MMU is ready to go */
-	if (!kvm->arch.mmu_ready)
-		kvmhv_setup_mmu(vcpu);
+	if (!kvm->arch.mmu_ready) {
+		r = kvmhv_setup_mmu(vcpu);
+		if (r) {
+			run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+			run->fail_entry.hardware_entry_failure_reason = 0;
+			vcpu->arch.ret = r;
+			return r;
+		}
+	}
 
 	if (need_resched())
 		cond_resched();
@@ -4254,7 +4261,8 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
 	preempt_disable();
 	pcpu = smp_processor_id();
 	vc->pcpu = pcpu;
-	kvmppc_prepare_radix_vcpu(vcpu, pcpu);
+	if (kvm_is_radix(kvm))
+		kvmppc_prepare_radix_vcpu(vcpu, pcpu);
 
 	local_irq_disable();
 	hard_irq_disable();
@@ -4454,7 +4462,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
 	vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
 
 	do {
-		if (kvm_is_radix(kvm))
+		if (radix_enabled())
 			r = kvmhv_run_single_vcpu(vcpu, ~(u64)0,
 						  vcpu->arch.vcore->lpcr);
 		else
diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index cd84d2c37632..03fbfef708a8 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -55,6 +55,50 @@ static void __accumulate_time(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator
 #define accumulate_time(vcpu, next) do {} while (0)
 #endif
 
+static inline void mfslb(unsigned int idx, u64 *slbee, u64 *slbev)
+{
+	asm volatile("slbmfev  %0,%1" : "=r" (*slbev) : "r" (idx));
+	asm volatile("slbmfee  %0,%1" : "=r" (*slbee) : "r" (idx));
+}
+
+static inline void __mtslb(u64 slbee, u64 slbev)
+{
+	asm volatile("slbmte %0,%1" :: "r" (slbev), "r" (slbee));
+}
+
+static inline void mtslb(unsigned int idx, u64 slbee, u64 slbev)
+{
+	BUG_ON((slbee & 0xfff) != idx);
+
+	__mtslb(slbee, slbev);
+}
+
+static inline void slb_invalidate(unsigned int ih)
+{
+	asm volatile("slbia %0" :: "i"(ih));
+}
+
+/*
+ * Malicious or buggy radix guests may have inserted SLB entries
+ * (only 0..3 because radix always runs with UPRT=1), so these must
+ * be cleared here to avoid side-channels. slbmte is used rather
+ * than slbia, as it won't clear cached translations.
+ */
+static void radix_clear_slb(void)
+{
+	u64 slbee, slbev;
+	int i;
+
+	for (i = 0; i < 4; i++) {
+		mfslb(i, &slbee, &slbev);
+		if (unlikely(slbee || slbev)) {
+			slbee = i;
+			slbev = 0;
+			mtslb(i, slbee, slbev);
+		}
+	}
+}
+
 static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
 {
 	struct kvmppc_vcore *vc = vcpu->arch.vcore;
@@ -80,6 +124,31 @@ static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u6
 	kvmppc_check_need_tlb_flush(kvm, vc->pcpu, nested);
 }
 
+static void switch_mmu_to_guest_hpt(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr)
+{
+	struct kvm_nested_guest *nested = vcpu->arch.nested;
+	u32 lpid;
+	int i;
+
+	BUG_ON(nested);
+
+	lpid = kvm->arch.lpid;
+
+	mtspr(SPRN_LPID, lpid);
+	mtspr(SPRN_LPCR, lpcr);
+	mtspr(SPRN_PID, vcpu->arch.pid);
+
+	for (i = 0; i < vcpu->arch.slb_max; i++)
+		__mtslb(vcpu->arch.slb[i].orige, vcpu->arch.slb[i].origv);
+
+	isync();
+
+	/*
+	 * TLBIEL is not virtualised for HPT guests, so check_need_tlb_flush
+	 * is not required here.
+	 */
+}
+
 static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
 {
 	isync();
@@ -91,42 +160,30 @@ static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
 	isync();
 }
 
-static inline void mfslb(unsigned int idx, u64 *slbee, u64 *slbev)
-{
-	asm volatile("slbmfev  %0,%1" : "=r" (*slbev) : "r" (idx));
-	asm volatile("slbmfee  %0,%1" : "=r" (*slbee) : "r" (idx));
-}
-
-static inline void mtslb(unsigned int idx, u64 slbee, u64 slbev)
-{
-	BUG_ON((slbee & 0xfff) != idx);
-
-	asm volatile("slbmte %0,%1" :: "r" (slbev), "r" (slbee));
-}
-
-static inline void slb_invalidate(unsigned int ih)
-{
-	asm volatile("slbia %0" :: "i"(ih));
-}
-
-/*
- * Malicious or buggy radix guests may have inserted SLB entries
- * (only 0..3 because radix always runs with UPRT=1), so these must
- * be cleared here to avoid side-channels. slbmte is used rather
- * than slbia, as it won't clear cached translations.
- */
-static void radix_clear_slb(void)
+static void save_clear_guest_mmu(struct kvm *kvm, struct kvm_vcpu *vcpu)
 {
-	u64 slbee, slbev;
-	int i;
+	if (kvm_is_radix(kvm)) {
+		radix_clear_slb();
+	} else {
+		int i;
+		int nr = 0;
 
-	for (i = 0; i < 4; i++) {
-		mfslb(i, &slbee, &slbev);
-		if (unlikely(slbee || slbev)) {
-			slbee = i;
-			slbev = 0;
-			mtslb(i, slbee, slbev);
+		/*
+		 * This must run before switching to host (radix host can't
+		 * access all SLBs).
+		 */
+		for (i = 0; i < vcpu->arch.slb_nr; i++) {
+			u64 slbee, slbev;
+			mfslb(i, &slbee, &slbev);
+			if (slbee & SLB_ESID_V) {
+				vcpu->arch.slb[nr].orige = slbee | i;
+				vcpu->arch.slb[nr].origv = slbev;
+				nr++;
+			}
 		}
+		vcpu->arch.slb_max = nr;
+		mtslb(0, 0, 0);
+		slb_invalidate(6);
 	}
 }
 
@@ -234,10 +291,18 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	mtspr(SPRN_AMOR, ~0UL);
 
-	if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
-		__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
+	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_GUEST_HV_FAST;
+	if (kvm_is_radix(kvm)) {
+		if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+			__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
+		switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
+		if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+			__mtmsrd(0, 1); /* clear RI */
 
-	switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
+	} else {
+		__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
+		switch_mmu_to_guest_hpt(kvm, vcpu, lpcr);
+	}
 
 	/*
 	 * P9 suppresses the HDEC exception when LPCR[HDICE] = 0,
@@ -245,9 +310,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	 */
 	mtspr(SPRN_HDEC, hdec);
 
-	if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
-		__mtmsrd(0, 1); /* clear RI */
-
 	mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
 	mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
 	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
@@ -255,10 +317,7 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 
 	accumulate_time(vcpu, &vcpu->arch.guest_time);
 
-	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_GUEST_HV_FAST;
 	kvmppc_p9_enter_guest(vcpu);
-	// Radix host and guest means host never runs with guest MMU state
-	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_NONE;
 
 	accumulate_time(vcpu, &vcpu->arch.rm_intr);
 
@@ -359,8 +418,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 #endif
 	}
 
-	radix_clear_slb();
-
 	accumulate_time(vcpu, &vcpu->arch.rm_exit);
 
 	/* Advance host PURR/SPURR by the amount used by guest */
@@ -394,11 +451,14 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 		mtspr(SPRN_DAWRX1, host_dawrx1);
 	}
 
-	/*
-	 * Since this is radix, do a eieio; tlbsync; ptesync sequence in
-	 * case we interrupted the guest between a tlbie and a ptesync.
-	 */
-	asm volatile("eieio; tlbsync; ptesync");
+	if (kvm_is_radix(kvm)) {
+		/*
+		 * Since this is radix, do a eieio; tlbsync; ptesync sequence
+		 * in case we interrupted the guest between a tlbie and a
+		 * ptesync.
+		 */
+		asm volatile("eieio; tlbsync; ptesync");
+	}
 
 	/*
 	 * cp_abort is required if the processor supports local copy-paste
@@ -425,7 +485,9 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	/* HDEC must be at least as large as DEC, so decrementer_max fits */
 	mtspr(SPRN_HDEC, decrementer_max);
 
+	save_clear_guest_mmu(kvm, vcpu);
 	switch_mmu_to_host_radix(kvm, host_pidr);
+	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_NONE;
 
 	/*
 	 * If we are in real mode, only switch MMU on after the MMU is
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index 8cc73abbf42b..f487ebb3a70a 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -57,6 +57,10 @@ static int global_invalidates(struct kvm *kvm)
 	else
 		global = 1;
 
+	/* LPID has been switched to host if in virt mode so can't do local */
+	if (!global && (mfmsr() & (MSR_IR|MSR_DR)))
+		global = 1;
+
 	if (!global) {
 		/* any other core might now have stale TLB entries... */
 		smp_wmb();
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 564ca9feef35..5cbc26ebcf8e 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -885,14 +885,11 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	cmpdi	r3, 512		/* 1 microsecond */
 	blt	hdec_soon
 
-	/* For hash guest, clear out and reload the SLB */
-BEGIN_MMU_FTR_SECTION
-	/* Radix host won't have populated the SLB, so no need to clear */
+	/* Clear out and reload the SLB */
 	li	r6, 0
 	slbmte	r6, r6
 	PPC_SLBIA(6)
 	ptesync
-END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
 
 	/* Load up guest SLB entries (N.B. slb_max will be 0 for radix) */
 	lwz	r5,VCPU_SLB_MAX(r4)
@@ -1394,9 +1391,6 @@ guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
 	stw	r5,VCPU_SLB_MAX(r9)
 
 	/* load host SLB entries */
-BEGIN_MMU_FTR_SECTION
-	b	guest_bypass
-END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
 	ld	r8,PACA_SLBSHADOWPTR(r13)
 
 	.rept	SLB_NUM_BOLTED
@@ -3148,10 +3142,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_DAWR1)
 	PPC_SLBIA(6)
 	ptesync
 
-BEGIN_MMU_FTR_SECTION
-	b	4f
-END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
-
 	/* load host SLB entries */
 	ld	r8, PACA_SLBSHADOWPTR(r13)
 	.rept	SLB_NUM_BOLTED
@@ -3165,7 +3155,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
 3:	addi	r8, r8, 16
 	.endr
 
-4:	lwz	r7, KVM_HOST_LPID(r10)
+	lwz	r7, KVM_HOST_LPID(r10)
 	mtspr	SPRN_LPID, r7
 	mtspr	SPRN_PID, r0
 	ld	r8, KVM_HOST_LPCR(r10)
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 45/46] KVM: PPC: Book3S HV P9: implement hash host / hash guest support
From: Nicholas Piggin @ 2021-03-23  1:03 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

This additionally has to save and restore the host SLB, and also
ensure that the MMU is off while switching into the guest SLB.

P9 and later CPUs now always go via the P9 path.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_64_entry.S     |  6 +++++
 arch/powerpc/kvm/book3s_hv.c           |  4 ++-
 arch/powerpc/kvm/book3s_hv_interrupt.c | 35 ++++++++++++++++++++++----
 3 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_64_entry.S b/arch/powerpc/kvm/book3s_64_entry.S
index 845df5fefdbd..7cef6f5212d8 100644
--- a/arch/powerpc/kvm/book3s_64_entry.S
+++ b/arch/powerpc/kvm/book3s_64_entry.S
@@ -339,6 +339,12 @@ kvmppc_p9_exit_interrupt:
  * effort for a small bit of code. Lots of other things to do first.
  */
 kvmppc_p9_bad_interrupt:
+BEGIN_MMU_FTR_SECTION
+	/*
+	 * Hash host doesn't try to recover MMU (requires host SLB reload)
+	 */
+	b	.
+END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
 	/*
 	 * Set GUEST_MODE_NONE so the handler won't branch to KVM, and clear
 	 * MSR_RI in r12 ([H]SRR1) so the handler won't try to return.
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index c151a60c0daa..e732d65772b1 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4462,7 +4462,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
 	vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
 
 	do {
-		if (radix_enabled())
+		if (cpu_has_feature(CPU_FTR_ARCH_300))
 			r = kvmhv_run_single_vcpu(vcpu, ~(u64)0,
 						  vcpu->arch.vcore->lpcr);
 		else
@@ -5543,6 +5543,8 @@ static int kvmhv_enable_nested(struct kvm *kvm)
 		return -EPERM;
 	if (!cpu_has_feature(CPU_FTR_ARCH_300))
 		return -ENODEV;
+	if (!radix_enabled())
+		return -ENODEV;
 
 	/* kvm == NULL means the caller is testing if the capability exists */
 	if (kvm)
diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
index 03fbfef708a8..bd95d05219b7 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupt.c
+++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
@@ -149,7 +149,7 @@ static void switch_mmu_to_guest_hpt(struct kvm *kvm, struct kvm_vcpu *vcpu, u64
 	 */
 }
 
-static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
+static void switch_mmu_to_host(struct kvm *kvm, u32 pid)
 {
 	isync();
 	mtspr(SPRN_PID, pid);
@@ -158,6 +158,23 @@ static void switch_mmu_to_host_radix(struct kvm *kvm, u32 pid)
 	isync();
 	mtspr(SPRN_LPCR, kvm->arch.host_lpcr);
 	isync();
+
+	if (!radix_enabled())
+		slb_restore_bolted_realmode();
+}
+
+static void save_clear_host_mmu(struct kvm *kvm)
+{
+	if (!radix_enabled()) {
+		/*
+		 * Hash host could save and restore host SLB entries to
+		 * reduce SLB fault overheads of VM exits, but for now the
+		 * existing code clears all entries and restores just the
+		 * bolted ones when switching back to host.
+		 */
+		mtslb(0, 0, 0);
+		slb_invalidate(6);
+	}
 }
 
 static void save_clear_guest_mmu(struct kvm *kvm, struct kvm_vcpu *vcpu)
@@ -292,15 +309,23 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	mtspr(SPRN_AMOR, ~0UL);
 
 	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_GUEST_HV_FAST;
+
+	/*
+	 * Hash host, hash guest, or radix guest with prefetch bug, all have
+	 * to disable the MMU before switching to guest MMU state.
+	 */
+	if (!radix_enabled() || !kvm_is_radix(kvm) ||
+			cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
+		__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
+
+	save_clear_host_mmu(kvm);
+
 	if (kvm_is_radix(kvm)) {
-		if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
-			__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
 		switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
 		if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
 			__mtmsrd(0, 1); /* clear RI */
 
 	} else {
-		__mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
 		switch_mmu_to_guest_hpt(kvm, vcpu, lpcr);
 	}
 
@@ -486,7 +511,7 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
 	mtspr(SPRN_HDEC, decrementer_max);
 
 	save_clear_guest_mmu(kvm, vcpu);
-	switch_mmu_to_host_radix(kvm, host_pidr);
+	switch_mmu_to_host(kvm, host_pidr);
 	local_paca->kvm_hstate.in_guest = KVM_GUEST_MODE_NONE;
 
 	/*
-- 
2.23.0


^ permalink raw reply related

* [PATCH v4 46/46] KVM: PPC: Book3S HV: remove ISA v3.0 and v3.1 support from P7/8 path
From: Nicholas Piggin @ 2021-03-23  1:03 UTC (permalink / raw)
  To: kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210323010305.1045293-1-npiggin@gmail.com>

POWER9 and later processors always go via the P9 guest entry path now.
Remove the remaining support from the P7/8 path.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c            |  62 ++--
 arch/powerpc/kvm/book3s_hv_interrupts.S |   9 +-
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 404 +-----------------------
 arch/powerpc/platforms/powernv/idle.c   |  52 +--
 4 files changed, 39 insertions(+), 488 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index e732d65772b1..ad6a2501ab0f 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -130,9 +130,6 @@ static inline bool nesting_enabled(struct kvm *kvm)
 	return kvm->arch.nested_enable && kvm_is_radix(kvm);
 }
 
-/* If set, the threads on each CPU core have to be in the same MMU mode */
-static bool no_mixing_hpt_and_radix __read_mostly;
-
 static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu);
 
 /*
@@ -3090,9 +3087,6 @@ static void prepare_threads(struct kvmppc_vcore *vc)
 	for_each_runnable_thread(i, vcpu, vc) {
 		if (signal_pending(vcpu->arch.run_task))
 			vcpu->arch.ret = -EINTR;
-		else if (no_mixing_hpt_and_radix &&
-			 kvm_is_radix(vc->kvm) != radix_enabled())
-			vcpu->arch.ret = -EINVAL;
 		else if (vcpu->arch.vpa.update_pending ||
 			 vcpu->arch.slb_shadow.update_pending ||
 			 vcpu->arch.dtl.update_pending)
@@ -3299,6 +3293,9 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 	int trap;
 	bool is_power8;
 
+	if (WARN_ON_ONCE(cpu_has_feature(CPU_FTR_ARCH_300)))
+		return;
+
 	/*
 	 * Remove from the list any threads that have a signal pending
 	 * or need a VPA update done
@@ -3326,9 +3323,6 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 	 * Make sure we are running on primary threads, and that secondary
 	 * threads are offline.  Also check if the number of threads in this
 	 * guest are greater than the current system threads per guest.
-	 * On POWER9, we need to be not in independent-threads mode if
-	 * this is a HPT guest on a radix host machine where the
-	 * CPU threads may not be in different MMU modes.
 	 */
 	if ((controlled_threads > 1) &&
 	    ((vc->num_threads > threads_per_subcore) || !on_primary_thread())) {
@@ -3352,18 +3346,6 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 	if (vc->num_threads < target_threads)
 		collect_piggybacks(&core_info, target_threads);
 
-	/*
-	 * On radix, arrange for TLB flushing if necessary.
-	 * This has to be done before disabling interrupts since
-	 * it uses smp_call_function().
-	 */
-	pcpu = smp_processor_id();
-	if (kvm_is_radix(vc->kvm)) {
-		for (sub = 0; sub < core_info.n_subcores; ++sub)
-			for_each_runnable_thread(i, vcpu, core_info.vc[sub])
-				kvmppc_prepare_radix_vcpu(vcpu, pcpu);
-	}
-
 	/*
 	 * Hard-disable interrupts, and check resched flag and signals.
 	 * If we need to reschedule or deliver a signal, clean up
@@ -3396,8 +3378,7 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 	cmd_bit = stat_bit = 0;
 	split = core_info.n_subcores;
 	sip = NULL;
-	is_power8 = cpu_has_feature(CPU_FTR_ARCH_207S)
-		&& !cpu_has_feature(CPU_FTR_ARCH_300);
+	is_power8 = cpu_has_feature(CPU_FTR_ARCH_207S);
 
 	if (split > 1) {
 		sip = &split_info;
@@ -3691,8 +3672,7 @@ static inline bool hcall_is_xics(unsigned long req)
 }
 
 /*
- * Virtual-mode guest entry for POWER9 and later when the host and
- * guest are both using the radix MMU.  The LPIDR has already been set.
+ * Guest entry for POWER9 and later CPUs.
  */
 static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 			 unsigned long lpcr)
@@ -5706,11 +5686,25 @@ static int kvmhv_enable_dawr1(struct kvm *kvm)
 
 static bool kvmppc_hash_v3_possible(void)
 {
-	if (radix_enabled() && no_mixing_hpt_and_radix)
+	if (!cpu_has_feature(CPU_FTR_ARCH_300))
 		return false;
 
-	return cpu_has_feature(CPU_FTR_ARCH_300) &&
-		cpu_has_feature(CPU_FTR_HVMODE);
+	if (!cpu_has_feature(CPU_FTR_HVMODE))
+		return false;
+
+	/*
+	 * POWER9 chips before version 2.02 can't have some threads in
+	 * HPT mode and some in radix mode on the same core.
+	 */
+	if (radix_enabled()) {
+		unsigned int pvr = mfspr(SPRN_PVR);
+		if ((pvr >> 16) == PVR_POWER9 &&
+		    (((pvr & 0xe000) == 0 && (pvr & 0xfff) < 0x202) ||
+		     ((pvr & 0xe000) == 0x2000 && (pvr & 0xfff) < 0x101)))
+			return false;
+	}
+
+	return true;
 }
 
 static struct kvmppc_ops kvm_ops_hv = {
@@ -5854,18 +5848,6 @@ static int kvmppc_book3s_init_hv(void)
 	if (kvmppc_radix_possible())
 		r = kvmppc_radix_init();
 
-	/*
-	 * POWER9 chips before version 2.02 can't have some threads in
-	 * HPT mode and some in radix mode on the same core.
-	 */
-	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
-		unsigned int pvr = mfspr(SPRN_PVR);
-		if ((pvr >> 16) == PVR_POWER9 &&
-		    (((pvr & 0xe000) == 0 && (pvr & 0xfff) < 0x202) ||
-		     ((pvr & 0xe000) == 0x2000 && (pvr & 0xfff) < 0x101)))
-			no_mixing_hpt_and_radix = true;
-	}
-
 	r = kvmppc_uvmem_init();
 	if (r < 0)
 		pr_err("KVM-HV: kvmppc_uvmem_init failed %d\n", r);
diff --git a/arch/powerpc/kvm/book3s_hv_interrupts.S b/arch/powerpc/kvm/book3s_hv_interrupts.S
index 327417d79eac..4444f83cb133 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupts.S
+++ b/arch/powerpc/kvm/book3s_hv_interrupts.S
@@ -58,7 +58,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	/*
 	 * Put whatever is in the decrementer into the
 	 * hypervisor decrementer.
-	 * Because of a hardware deviation in P8 and P9,
+	 * Because of a hardware deviation in P8,
 	 * we need to set LPCR[HDICE] before writing HDEC.
 	 */
 	ld	r5, HSTATE_KVM_VCORE(r13)
@@ -67,15 +67,10 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	ori	r8, r9, LPCR_HDICE
 	mtspr	SPRN_LPCR, r8
 	isync
-	andis.	r0, r9, LPCR_LD@h
 	mfspr	r8,SPRN_DEC
 	mftb	r7
-BEGIN_FTR_SECTION
-	/* On POWER9, don't sign-extend if host LPCR[LD] bit is set */
-	bne	32f
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	extsw	r8,r8
-32:	mtspr	SPRN_HDEC,r8
+	mtspr	SPRN_HDEC,r8
 	add	r8,r8,r7
 	std	r8,HSTATE_DECEXP(r13)
 
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 5cbc26ebcf8e..b2a71a1b48fe 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -25,7 +25,6 @@
 #include <asm/export.h>
 #include <asm/tm.h>
 #include <asm/opal.h>
-#include <asm/xive-regs.h>
 #include <asm/thread_info.h>
 #include <asm/asm-compat.h>
 #include <asm/feature-fixups.h>
@@ -34,9 +33,7 @@
 
 /* Sign-extend HDEC if not on POWER9 */
 #define EXTEND_HDEC(reg)			\
-BEGIN_FTR_SECTION;				\
-	extsw	reg, reg;			\
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
+	extsw	reg, reg
 
 /* Values in HSTATE_NAPPING(r13) */
 #define NAPPING_CEDE	1
@@ -56,8 +53,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 #define STACK_SLOT_HFSCR	(SFS-72)
 #define STACK_SLOT_AMR		(SFS-80)
 #define STACK_SLOT_UAMOR	(SFS-88)
-#define STACK_SLOT_DAWR1	(SFS-96)
-#define STACK_SLOT_DAWRX1	(SFS-104)
 
 /*
  * Call kvmppc_hv_entry in real mode.
@@ -333,7 +328,6 @@ kvm_secondary_got_guest:
 	LOAD_REG_ADDR(r6, decrementer_max)
 	ld	r6, 0(r6)
 	mtspr	SPRN_HDEC, r6
-BEGIN_FTR_SECTION
 	/* and set per-LPAR registers, if doing dynamic micro-threading */
 	ld	r6, HSTATE_SPLIT_MODE(r13)
 	cmpdi	r6, 0
@@ -345,7 +339,6 @@ BEGIN_FTR_SECTION
 	ld	r0, KVM_SPLIT_LDBAR(r6)
 	mtspr	SPRN_LDBAR, r0
 	isync
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 63:
 	/* Order load of vcpu after load of vcore */
 	lwsync
@@ -416,7 +409,6 @@ kvm_no_guest:
 	blr
 
 53:
-BEGIN_FTR_SECTION
 	HMT_LOW
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	cmpdi	r5, 0
@@ -431,14 +423,6 @@ BEGIN_FTR_SECTION
 	b	kvm_unsplit_nap
 60:	HMT_MEDIUM
 	b	kvm_secondary_got_guest
-FTR_SECTION_ELSE
-	HMT_LOW
-	ld	r5, HSTATE_KVM_VCORE(r13)
-	cmpdi	r5, 0
-	beq	kvm_no_guest
-	HMT_MEDIUM
-	b	kvm_secondary_got_guest
-ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 
 54:	li	r0, KVM_HWTHREAD_IN_KVM
 	stb	r0, HSTATE_HWTHREAD_STATE(r13)
@@ -564,13 +548,11 @@ kvmppc_hv_entry:
 	bne	10f
 
 	lwz	r7,KVM_LPID(r9)
-BEGIN_FTR_SECTION
 	ld	r6,KVM_SDR1(r9)
 	li	r0,LPID_RSVD		/* switch to reserved LPID */
 	mtspr	SPRN_LPID,r0
 	ptesync
 	mtspr	SPRN_SDR1,r6		/* switch to partition page table */
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	mtspr	SPRN_LPID,r7
 	isync
 
@@ -650,16 +632,6 @@ kvmppc_got_guest:
 	mtspr	SPRN_SPURR,r8
 
 	/* Save host values of some registers */
-BEGIN_FTR_SECTION
-	mfspr	r5, SPRN_TIDR
-	mfspr	r6, SPRN_PSSCR
-	mfspr	r7, SPRN_PID
-	std	r5, STACK_SLOT_TID(r1)
-	std	r6, STACK_SLOT_PSSCR(r1)
-	std	r7, STACK_SLOT_PID(r1)
-	mfspr	r5, SPRN_HFSCR
-	std	r5, STACK_SLOT_HFSCR(r1)
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_CIABR
 	mfspr	r6, SPRN_DAWR0
@@ -670,12 +642,6 @@ BEGIN_FTR_SECTION
 	std	r7, STACK_SLOT_DAWRX0(r1)
 	std	r8, STACK_SLOT_IAMR(r1)
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-BEGIN_FTR_SECTION
-	mfspr	r6, SPRN_DAWR1
-	mfspr	r7, SPRN_DAWRX1
-	std	r6, STACK_SLOT_DAWR1(r1)
-	std	r7, STACK_SLOT_DAWRX1(r1)
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S | CPU_FTR_DAWR1)
 
 	mfspr	r5, SPRN_AMR
 	std	r5, STACK_SLOT_AMR(r1)
@@ -693,13 +659,9 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-/*
- * Branch around the call if both CPU_FTR_TM and
- * CPU_FTR_P9_TM_HV_ASSIST are off.
- */
 BEGIN_FTR_SECTION
 	b	91f
-END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
+END_FTR_SECTION_IFCLR(CPU_FTR_TM)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
@@ -766,12 +728,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	ld	r6, VCPU_DAWRX0(r4)
 	mtspr	SPRN_DAWR0, r5
 	mtspr	SPRN_DAWRX0, r6
-BEGIN_FTR_SECTION
-	ld	r5, VCPU_DAWR1(r4)
-	ld	r6, VCPU_DAWRX1(r4)
-	mtspr	SPRN_DAWR1, r5
-	mtspr	SPRN_DAWRX1, r6
-END_FTR_SECTION_IFSET(CPU_FTR_DAWR1)
 1:
 	ld	r7, VCPU_CIABR(r4)
 	ld	r8, VCPU_TAR(r4)
@@ -789,7 +745,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_DAWR1)
 	mtspr	SPRN_BESCR, r6
 	mtspr	SPRN_PID, r7
 	mtspr	SPRN_WORT, r8
-BEGIN_FTR_SECTION
 	/* POWER8-only registers */
 	ld	r5, VCPU_TCSCR(r4)
 	ld	r6, VCPU_ACOP(r4)
@@ -800,18 +755,6 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_CSIGR, r7
 	mtspr	SPRN_TACR, r8
 	nop
-FTR_SECTION_ELSE
-	/* POWER9-only registers */
-	ld	r5, VCPU_TID(r4)
-	ld	r6, VCPU_PSSCR(r4)
-	lbz	r8, HSTATE_FAKE_SUSPEND(r13)
-	oris	r6, r6, PSSCR_EC@h	/* This makes stop trap to HV */
-	rldimi	r6, r8, PSSCR_FAKE_SUSPEND_LG, 63 - PSSCR_FAKE_SUSPEND_LG
-	ld	r7, VCPU_HFSCR(r4)
-	mtspr	SPRN_TIDR, r5
-	mtspr	SPRN_PSSCR, r6
-	mtspr	SPRN_HFSCR, r7
-ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 8:
 
 	ld	r5, VCPU_SPRG0(r4)
@@ -904,93 +847,9 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	bdnz	1b
 9:
 
-#ifdef CONFIG_KVM_XICS
-	/* We are entering the guest on that thread, push VCPU to XIVE */
-	ld	r11, VCPU_XIVE_SAVED_STATE(r4)
-	li	r9, TM_QW1_OS
-	lwz	r8, VCPU_XIVE_CAM_WORD(r4)
-	cmpwi	r8, 0
-	beq	no_xive
-	li	r7, TM_QW1_OS + TM_WORD2
-	mfmsr	r0
-	andi.	r0, r0, MSR_DR		/* in real mode? */
-	beq	2f
-	ld	r10, HSTATE_XIVE_TIMA_VIRT(r13)
-	cmpldi	cr1, r10, 0
-	beq     cr1, no_xive
-	eieio
-	stdx	r11,r9,r10
-	stwx	r8,r7,r10
-	b	3f
-2:	ld	r10, HSTATE_XIVE_TIMA_PHYS(r13)
-	cmpldi	cr1, r10, 0
-	beq	cr1, no_xive
-	eieio
-	stdcix	r11,r9,r10
-	stwcix	r8,r7,r10
-3:	li	r9, 1
-	stb	r9, VCPU_XIVE_PUSHED(r4)
-	eieio
-
-	/*
-	 * We clear the irq_pending flag. There is a small chance of a
-	 * race vs. the escalation interrupt happening on another
-	 * processor setting it again, but the only consequence is to
-	 * cause a spurrious wakeup on the next H_CEDE which is not an
-	 * issue.
-	 */
-	li	r0,0
-	stb	r0, VCPU_IRQ_PENDING(r4)
-
-	/*
-	 * In single escalation mode, if the escalation interrupt is
-	 * on, we mask it.
-	 */
-	lbz	r0, VCPU_XIVE_ESC_ON(r4)
-	cmpwi	cr1, r0,0
-	beq	cr1, 1f
-	li	r9, XIVE_ESB_SET_PQ_01
-	beq	4f			/* in real mode? */
-	ld	r10, VCPU_XIVE_ESC_VADDR(r4)
-	ldx	r0, r10, r9
-	b	5f
-4:	ld	r10, VCPU_XIVE_ESC_RADDR(r4)
-	ldcix	r0, r10, r9
-5:	sync
-
-	/* We have a possible subtle race here: The escalation interrupt might
-	 * have fired and be on its way to the host queue while we mask it,
-	 * and if we unmask it early enough (re-cede right away), there is
-	 * a theorical possibility that it fires again, thus landing in the
-	 * target queue more than once which is a big no-no.
-	 *
-	 * Fortunately, solving this is rather easy. If the above load setting
-	 * PQ to 01 returns a previous value where P is set, then we know the
-	 * escalation interrupt is somewhere on its way to the host. In that
-	 * case we simply don't clear the xive_esc_on flag below. It will be
-	 * eventually cleared by the handler for the escalation interrupt.
-	 *
-	 * Then, when doing a cede, we check that flag again before re-enabling
-	 * the escalation interrupt, and if set, we abort the cede.
-	 */
-	andi.	r0, r0, XIVE_ESB_VAL_P
-	bne-	1f
-
-	/* Now P is 0, we can clear the flag */
-	li	r0, 0
-	stb	r0, VCPU_XIVE_ESC_ON(r4)
-1:
-no_xive:
-#endif /* CONFIG_KVM_XICS */
-
 deliver_guest_interrupt:	/* r4 = vcpu, r13 = paca */
 	/* Check if we can deliver an external or decrementer interrupt now */
 	ld	r0, VCPU_PENDING_EXC(r4)
-BEGIN_FTR_SECTION
-	/* On POWER9, also check for emulated doorbell interrupt */
-	lbz	r3, VCPU_DBELL_REQ(r4)
-	or	r0, r0, r3
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	cmpdi	r0, 0
 	beq	71f
 	mr	r3, r4
@@ -1063,12 +922,6 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_PPR, r0
 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 
-/* Move canary into DSISR to check for later */
-BEGIN_FTR_SECTION
-	li	r0, 0x7fff
-	mtspr	SPRN_HDSISR, r0
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
-
 	ld	r6, VCPU_KVM(r4)
 	lbz	r7, KVM_SECURE_GUEST(r6)
 	cmpdi	r7, 0
@@ -1284,14 +1137,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	/* Hypervisor doorbell - exit only if host IPI flag set */
 	cmpwi	r12, BOOK3S_INTERRUPT_H_DOORBELL
 	bne	3f
-BEGIN_FTR_SECTION
-	PPC_MSGSYNC
-	lwsync
-	/* always exit if we're running a nested guest */
-	ld	r0, VCPU_NESTED(r9)
-	cmpdi	r0, 0
-	bne	guest_exit_cont
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	lbz	r0, HSTATE_HOST_IPI(r13)
 	cmpwi	r0, 0
 	beq	maybe_reenter_guest
@@ -1321,43 +1166,6 @@ guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
 	mr	r4, r9
 	bl	kvmhv_accumulate_time
 #endif
-#ifdef CONFIG_KVM_XICS
-	/* We are exiting, pull the VP from the XIVE */
-	lbz	r0, VCPU_XIVE_PUSHED(r9)
-	cmpwi	cr0, r0, 0
-	beq	1f
-	li	r7, TM_SPC_PULL_OS_CTX
-	li	r6, TM_QW1_OS
-	mfmsr	r0
-	andi.	r0, r0, MSR_DR		/* in real mode? */
-	beq	2f
-	ld	r10, HSTATE_XIVE_TIMA_VIRT(r13)
-	cmpldi	cr0, r10, 0
-	beq	1f
-	/* First load to pull the context, we ignore the value */
-	eieio
-	lwzx	r11, r7, r10
-	/* Second load to recover the context state (Words 0 and 1) */
-	ldx	r11, r6, r10
-	b	3f
-2:	ld	r10, HSTATE_XIVE_TIMA_PHYS(r13)
-	cmpldi	cr0, r10, 0
-	beq	1f
-	/* First load to pull the context, we ignore the value */
-	eieio
-	lwzcix	r11, r7, r10
-	/* Second load to recover the context state (Words 0 and 1) */
-	ldcix	r11, r6, r10
-3:	std	r11, VCPU_XIVE_SAVED_STATE(r9)
-	/* Fixup some of the state for the next load */
-	li	r10, 0
-	li	r0, 0xff
-	stb	r10, VCPU_XIVE_PUSHED(r9)
-	stb	r10, (VCPU_XIVE_SAVED_STATE+3)(r9)
-	stb	r0, (VCPU_XIVE_SAVED_STATE+4)(r9)
-	eieio
-1:
-#endif /* CONFIG_KVM_XICS */
 
 	/*
 	 * Possibly flush the link stack here, before we do a blr in
@@ -1412,12 +1220,6 @@ guest_bypass:
 	ld	r3, HSTATE_KVM_VCORE(r13)
 	mfspr	r5,SPRN_DEC
 	mftb	r6
-	/* On P9, if the guest has large decr enabled, don't sign extend */
-BEGIN_FTR_SECTION
-	ld	r4, VCORE_LPCR(r3)
-	andis.	r4, r4, LPCR_LD@h
-	bne	16f
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	extsw	r5,r5
 16:	add	r5,r5,r6
 	/* r5 is a guest timebase value here, convert to host TB */
@@ -1491,7 +1293,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	std	r6, VCPU_BESCR(r9)
 	stw	r7, VCPU_GUEST_PID(r9)
 	std	r8, VCPU_WORT(r9)
-BEGIN_FTR_SECTION
 	mfspr	r5, SPRN_TCSCR
 	mfspr	r6, SPRN_ACOP
 	mfspr	r7, SPRN_CSIGR
@@ -1500,17 +1301,6 @@ BEGIN_FTR_SECTION
 	std	r6, VCPU_ACOP(r9)
 	std	r7, VCPU_CSIGR(r9)
 	std	r8, VCPU_TACR(r9)
-FTR_SECTION_ELSE
-	mfspr	r5, SPRN_TIDR
-	mfspr	r6, SPRN_PSSCR
-	std	r5, VCPU_TID(r9)
-	rldicl	r6, r6, 4, 50		/* r6 &= PSSCR_GUEST_VIS */
-	rotldi	r6, r6, 60
-	std	r6, VCPU_PSSCR(r9)
-	/* Restore host HFSCR value */
-	ld	r7, STACK_SLOT_HFSCR(r1)
-	mtspr	SPRN_HFSCR, r7
-ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	/*
 	 * Restore various registers to 0, where non-zero values
 	 * set by the guest could disrupt the host.
@@ -1518,13 +1308,11 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 	li	r0, 0
 	mtspr	SPRN_PSPB, r0
 	mtspr	SPRN_WORT, r0
-BEGIN_FTR_SECTION
 	mtspr	SPRN_TCSCR, r0
 	/* Set MMCRS to 1<<31 to freeze and disable the SPMC counters */
 	li	r0, 1
 	sldi	r0, r0, 31
 	mtspr	SPRN_MMCRS, r0
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 
 	/* Save and restore AMR, IAMR and UAMOR before turning on the MMU */
 	ld	r8, STACK_SLOT_IAMR(r1)
@@ -1581,13 +1369,9 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	bl	kvmppc_save_fp
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-/*
- * Branch around the call if both CPU_FTR_TM and
- * CPU_FTR_P9_TM_HV_ASSIST are off.
- */
 BEGIN_FTR_SECTION
 	b	91f
-END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
+END_FTR_SECTION_IFCLR(CPU_FTR_TM)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
@@ -1633,28 +1417,6 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_DAWR0, r6
 	mtspr	SPRN_DAWRX0, r7
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-BEGIN_FTR_SECTION
-	ld	r6, STACK_SLOT_DAWR1(r1)
-	ld	r7, STACK_SLOT_DAWRX1(r1)
-	mtspr	SPRN_DAWR1, r6
-	mtspr	SPRN_DAWRX1, r7
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S | CPU_FTR_DAWR1)
-BEGIN_FTR_SECTION
-	ld	r5, STACK_SLOT_TID(r1)
-	ld	r6, STACK_SLOT_PSSCR(r1)
-	ld	r7, STACK_SLOT_PID(r1)
-	mtspr	SPRN_TIDR, r5
-	mtspr	SPRN_PSSCR, r6
-	mtspr	SPRN_PID, r7
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
-
-	/*
-	 * cp_abort is required if the processor supports local copy-paste
-	 * to clear the copy buffer that was under control of the guest.
-	 */
-BEGIN_FTR_SECTION
-	PPC_CP_ABORT
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_31)
 
 	/*
 	 * POWER7/POWER8 guest -> host partition switch code.
@@ -1691,13 +1453,11 @@ kvmhv_switch_to_host:
 
 	/* Primary thread switches back to host partition */
 	lwz	r7,KVM_HOST_LPID(r4)
-BEGIN_FTR_SECTION
 	ld	r6,KVM_HOST_SDR1(r4)
 	li	r8,LPID_RSVD		/* switch to reserved LPID */
 	mtspr	SPRN_LPID,r8
 	ptesync
 	mtspr	SPRN_SDR1,r6		/* switch to host page table */
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	mtspr	SPRN_LPID,r7
 	isync
 
@@ -1908,20 +1668,11 @@ kvmppc_tm_emul:
 kvmppc_hdsi:
 	mfspr	r4, SPRN_HDAR
 	mfspr	r6, SPRN_HDSISR
-BEGIN_FTR_SECTION
-	/* Look for DSISR canary. If we find it, retry instruction */
-	cmpdi	r6, 0x7fff
-	beq	6f
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	/* HPTE not found fault or protection fault? */
 	andis.	r0, r6, (DSISR_NOHPTE | DSISR_PROTFAULT)@h
 	beq	1f			/* if not, send it to the guest */
 	andi.	r0, r11, MSR_DR		/* data relocation enabled? */
 	beq	3f
-BEGIN_FTR_SECTION
-	mfspr	r5, SPRN_ASDR		/* on POWER9, use ASDR to get VSID */
-	b	4f
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	clrrdi	r0, r4, 28
 	PPC_SLBFEE_DOT(R5, R0)		/* if so, look up SLB */
 	li	r0, BOOK3S_INTERRUPT_DATA_SEGMENT
@@ -1998,10 +1749,6 @@ kvmppc_hisi:
 	beq	1f
 	andi.	r0, r11, MSR_IR		/* instruction relocation enabled? */
 	beq	3f
-BEGIN_FTR_SECTION
-	mfspr	r5, SPRN_ASDR		/* on POWER9, use ASDR to get VSID */
-	b	4f
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	clrrdi	r0, r10, 28
 	PPC_SLBFEE_DOT(R5, R0)		/* if so, look up SLB */
 	li	r0, BOOK3S_INTERRUPT_INST_SEGMENT
@@ -2049,10 +1796,6 @@ hcall_try_real_mode:
 	andi.	r0,r11,MSR_PR
 	/* sc 1 from userspace - reflect to guest syscall */
 	bne	sc_1_fast_return
-	/* sc 1 from nested guest - give it to L1 to handle */
-	ld	r0, VCPU_NESTED(r9)
-	cmpdi	r0, 0
-	bne	guest_exit_cont
 	clrrdi	r3,r3,2
 	cmpldi	r3,hcall_real_table_end - hcall_real_table
 	bge	guest_exit_cont
@@ -2448,13 +2191,9 @@ _GLOBAL(kvmppc_h_cede)		/* r3 = vcpu pointer, r11 = msr, r13 = paca */
 	bl	kvmppc_save_fp
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-/*
- * Branch around the call if both CPU_FTR_TM and
- * CPU_FTR_P9_TM_HV_ASSIST are off.
- */
 BEGIN_FTR_SECTION
 	b	91f
-END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
+END_FTR_SECTION_IFCLR(CPU_FTR_TM)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
@@ -2474,15 +2213,8 @@ END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	mfspr	r3, SPRN_DEC
 	mfspr	r4, SPRN_HDEC
 	mftb	r5
-BEGIN_FTR_SECTION
-	/* On P9 check whether the guest has large decrementer mode enabled */
-	ld	r6, HSTATE_KVM_VCORE(r13)
-	ld	r6, VCORE_LPCR(r6)
-	andis.	r6, r6, LPCR_LD@h
-	bne	68f
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	extsw	r3, r3
-68:	EXTEND_HDEC(r4)
+	EXTEND_HDEC(r4)
 	cmpd	r3, r4
 	ble	67f
 	mtspr	SPRN_DEC, r4
@@ -2527,28 +2259,14 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 
 kvm_nap_sequence:		/* desired LPCR value in r5 */
-BEGIN_FTR_SECTION
-	/*
-	 * PSSCR bits:	exit criterion = 1 (wakeup based on LPCR at sreset)
-	 *		enable state loss = 1 (allow SMT mode switch)
-	 *		requested level = 0 (just stop dispatching)
-	 */
-	lis	r3, (PSSCR_EC | PSSCR_ESL)@h
 	/* Set LPCR_PECE_HVEE bit to enable wakeup by HV interrupts */
 	li	r4, LPCR_PECE_HVEE@higher
 	sldi	r4, r4, 32
 	or	r5, r5, r4
-FTR_SECTION_ELSE
-	li	r3, PNV_THREAD_NAP
-ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
 	mtspr	SPRN_LPCR,r5
 	isync
 
-BEGIN_FTR_SECTION
-	bl	isa300_idle_stop_mayloss
-FTR_SECTION_ELSE
 	bl	isa206_idle_insn_mayloss
-ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
 
 	mfspr	r0, SPRN_CTRLF
 	ori	r0, r0, 1
@@ -2567,10 +2285,8 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
 	beq	kvm_end_cede
 	cmpwi	r0, NAPPING_NOVCPU
 	beq	kvm_novcpu_wakeup
-BEGIN_FTR_SECTION
 	cmpwi	r0, NAPPING_UNSPLIT
 	beq	kvm_unsplit_wakeup
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 	twi	31,0,0 /* Nap state must not be zero */
 
 33:	mr	r4, r3
@@ -2590,13 +2306,9 @@ kvm_end_cede:
 #endif
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-/*
- * Branch around the call if both CPU_FTR_TM and
- * CPU_FTR_P9_TM_HV_ASSIST are off.
- */
 BEGIN_FTR_SECTION
 	b	91f
-END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
+END_FTR_SECTION_IFCLR(CPU_FTR_TM)
 	/*
 	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
@@ -2686,47 +2398,7 @@ kvm_cede_prodded:
 	/* we've ceded but we want to give control to the host */
 kvm_cede_exit:
 	ld	r9, HSTATE_KVM_VCPU(r13)
-#ifdef CONFIG_KVM_XICS
-	/* are we using XIVE with single escalation? */
-	ld	r10, VCPU_XIVE_ESC_VADDR(r9)
-	cmpdi	r10, 0
-	beq	3f
-	li	r6, XIVE_ESB_SET_PQ_00
-	/*
-	 * If we still have a pending escalation, abort the cede,
-	 * and we must set PQ to 10 rather than 00 so that we don't
-	 * potentially end up with two entries for the escalation
-	 * interrupt in the XIVE interrupt queue.  In that case
-	 * we also don't want to set xive_esc_on to 1 here in
-	 * case we race with xive_esc_irq().
-	 */
-	lbz	r5, VCPU_XIVE_ESC_ON(r9)
-	cmpwi	r5, 0
-	beq	4f
-	li	r0, 0
-	stb	r0, VCPU_CEDED(r9)
-	/*
-	 * The escalation interrupts are special as we don't EOI them.
-	 * There is no need to use the load-after-store ordering offset
-	 * to set PQ to 10 as we won't use StoreEOI.
-	 */
-	li	r6, XIVE_ESB_SET_PQ_10
-	b	5f
-4:	li	r0, 1
-	stb	r0, VCPU_XIVE_ESC_ON(r9)
-	/* make sure store to xive_esc_on is seen before xive_esc_irq runs */
-	sync
-5:	/* Enable XIVE escalation */
-	mfmsr	r0
-	andi.	r0, r0, MSR_DR		/* in real mode? */
-	beq	1f
-	ldx	r0, r10, r6
-	b	2f
-1:	ld	r10, VCPU_XIVE_ESC_RADDR(r9)
-	ldcix	r0, r10, r6
-2:	sync
-#endif /* CONFIG_KVM_XICS */
-3:	b	guest_exit_cont
+	b	guest_exit_cont
 
 	/* Try to do machine check recovery in real mode */
 machine_check_realmode:
@@ -2803,10 +2475,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	PPC_MSGCLR(6)
 	/* see if it's a host IPI */
 	li	r3, 1
-BEGIN_FTR_SECTION
-	PPC_MSGSYNC
-	lwsync
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	lbz	r0, HSTATE_HOST_IPI(r13)
 	cmpwi	r0, 0
 	bnelr
@@ -3115,70 +2783,12 @@ kvmppc_bad_host_intr:
 	std	r3, STACK_FRAME_OVERHEAD-16(r1)
 
 	/*
-	 * On POWER9 do a minimal restore of the MMU and call C code,
-	 * which will print a message and panic.
 	 * XXX On POWER7 and POWER8, we just spin here since we don't
 	 * know what the other threads are doing (and we don't want to
 	 * coordinate with them) - but at least we now have register state
 	 * in memory that we might be able to look at from another CPU.
 	 */
-BEGIN_FTR_SECTION
 	b	.
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
-	ld	r9, HSTATE_KVM_VCPU(r13)
-	ld	r10, VCPU_KVM(r9)
-
-	li	r0, 0
-	mtspr	SPRN_AMR, r0
-	mtspr	SPRN_IAMR, r0
-	mtspr	SPRN_CIABR, r0
-	mtspr	SPRN_DAWRX0, r0
-BEGIN_FTR_SECTION
-	mtspr	SPRN_DAWRX1, r0
-END_FTR_SECTION_IFSET(CPU_FTR_DAWR1)
-
-	/* Clear guest SLB. */
-	slbmte	r0, r0
-	PPC_SLBIA(6)
-	ptesync
-
-	/* load host SLB entries */
-	ld	r8, PACA_SLBSHADOWPTR(r13)
-	.rept	SLB_NUM_BOLTED
-	li	r3, SLBSHADOW_SAVEAREA
-	LDX_BE	r5, r8, r3
-	addi	r3, r3, 8
-	LDX_BE	r6, r8, r3
-	andis.	r7, r5, SLB_ESID_V@h
-	beq	3f
-	slbmte	r6, r5
-3:	addi	r8, r8, 16
-	.endr
-
-	lwz	r7, KVM_HOST_LPID(r10)
-	mtspr	SPRN_LPID, r7
-	mtspr	SPRN_PID, r0
-	ld	r8, KVM_HOST_LPCR(r10)
-	mtspr	SPRN_LPCR, r8
-	isync
-	li	r0, KVM_GUEST_MODE_NONE
-	stb	r0, HSTATE_IN_GUEST(r13)
-
-	/*
-	 * Turn on the MMU and jump to C code
-	 */
-	bcl	20, 31, .+4
-5:	mflr	r3
-	addi	r3, r3, 9f - 5b
-	li	r4, -1
-	rldimi	r3, r4, 62, 0	/* ensure 0xc000000000000000 bits are set */
-	ld	r4, PACAKMSR(r13)
-	mtspr	SPRN_SRR0, r3
-	mtspr	SPRN_SRR1, r4
-	RFI_TO_KERNEL
-9:	addi	r3, r1, STACK_FRAME_OVERHEAD
-	bl	kvmppc_bad_interrupt
-	b	9b
 
 /*
  * This mimics the MSR transition on IRQ delivery.  The new guest MSR is taken
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index 999997d9e9a9..528a7e0cf83a 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -604,7 +604,7 @@ struct p9_sprs {
 	u64 uamor;
 };
 
-static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
+static unsigned long power9_idle_stop(unsigned long psscr)
 {
 	int cpu = raw_smp_processor_id();
 	int first = cpu_first_thread_sibling(cpu);
@@ -620,8 +620,6 @@ static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
 	if (!(psscr & (PSSCR_EC|PSSCR_ESL))) {
 		/* EC=ESL=0 case */
 
-		BUG_ON(!mmu_on);
-
 		/*
 		 * Wake synchronously. SRESET via xscom may still cause
 		 * a 0x100 powersave wakeup with SRR1 reason!
@@ -803,8 +801,7 @@ static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
 		__slb_restore_bolted_realmode();
 
 out:
-	if (mmu_on)
-		mtmsr(MSR_KERNEL);
+	mtmsr(MSR_KERNEL);
 
 	return srr1;
 }
@@ -895,7 +892,7 @@ struct p10_sprs {
 	 */
 };
 
-static unsigned long power10_idle_stop(unsigned long psscr, bool mmu_on)
+static unsigned long power10_idle_stop(unsigned long psscr)
 {
 	int cpu = raw_smp_processor_id();
 	int first = cpu_first_thread_sibling(cpu);
@@ -909,8 +906,6 @@ static unsigned long power10_idle_stop(unsigned long psscr, bool mmu_on)
 	if (!(psscr & (PSSCR_EC|PSSCR_ESL))) {
 		/* EC=ESL=0 case */
 
-		BUG_ON(!mmu_on);
-
 		/*
 		 * Wake synchronously. SRESET via xscom may still cause
 		 * a 0x100 powersave wakeup with SRR1 reason!
@@ -991,8 +986,7 @@ static unsigned long power10_idle_stop(unsigned long psscr, bool mmu_on)
 		__slb_restore_bolted_realmode();
 
 out:
-	if (mmu_on)
-		mtmsr(MSR_KERNEL);
+	mtmsr(MSR_KERNEL);
 
 	return srr1;
 }
@@ -1002,40 +996,10 @@ static unsigned long arch300_offline_stop(unsigned long psscr)
 {
 	unsigned long srr1;
 
-#ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-	__ppc64_runlatch_off();
 	if (cpu_has_feature(CPU_FTR_ARCH_31))
-		srr1 = power10_idle_stop(psscr, true);
+		srr1 = power10_idle_stop(psscr);
 	else
-		srr1 = power9_idle_stop(psscr, true);
-	__ppc64_runlatch_on();
-#else
-	/*
-	 * Tell KVM we're entering idle.
-	 * This does not have to be done in real mode because the P9 MMU
-	 * is independent per-thread. Some steppings share radix/hash mode
-	 * between threads, but in that case KVM has a barrier sync in real
-	 * mode before and after switching between radix and hash.
-	 *
-	 * kvm_start_guest must still be called in real mode though, hence
-	 * the false argument.
-	 */
-	local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_IDLE;
-
-	__ppc64_runlatch_off();
-	if (cpu_has_feature(CPU_FTR_ARCH_31))
-		srr1 = power10_idle_stop(psscr, false);
-	else
-		srr1 = power9_idle_stop(psscr, false);
-	__ppc64_runlatch_on();
-
-	local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_KERNEL;
-	/* Order setting hwthread_state vs. testing hwthread_req */
-	smp_mb();
-	if (local_paca->kvm_hstate.hwthread_req)
-		srr1 = idle_kvm_start_guest(srr1);
-	mtmsr(MSR_KERNEL);
-#endif
+		srr1 = power9_idle_stop(psscr);
 
 	return srr1;
 }
@@ -1055,9 +1019,9 @@ void arch300_idle_type(unsigned long stop_psscr_val,
 
 	__ppc64_runlatch_off();
 	if (cpu_has_feature(CPU_FTR_ARCH_31))
-		srr1 = power10_idle_stop(psscr, true);
+		srr1 = power10_idle_stop(psscr);
 	else
-		srr1 = power9_idle_stop(psscr, true);
+		srr1 = power9_idle_stop(psscr);
 	__ppc64_runlatch_on();
 
 	fini_irq_for_idle_irqsoff();
-- 
2.23.0


^ permalink raw reply related

* Re: [PATCH v11 0/6] KASAN for powerpc64 radix
From: Daniel Axtens @ 2021-03-23  1:21 UTC (permalink / raw)
  To: Christophe Leroy, linux-kernel, linux-mm, linuxppc-dev, kasan-dev,
	aneesh.kumar, bsingharora
In-Reply-To: <5a3b5952-b31f-42bf-eaf4-ea24444f8df6@csgroup.eu>

Hi Christophe,

> In the discussion we had long time ago, 
> https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20190806233827.16454-5-dja@axtens.net/#2321067 
> , I challenged you on why it was not possible to implement things the same way as other 
> architectures, in extenso with an early mapping.
>
> Your first answer was that too many things were done in real mode at startup. After some discussion 
> you said that finally there was not that much things at startup but the issue was KVM.
>
> Now you say that instrumentation on KVM is fully disabled.
>
> So my question is, if KVM is not a problem anymore, why not go the standard way with an early shadow 
> ? Then you could also support inline instrumentation.

Fair enough, I've had some trouble both understanding the problem myself
and clearly articulating it. Let me try again.

We need translations on to access the shadow area.

We reach setup_64.c::early_setup() with translations off. At this point
we don't know what MMU we're running under, or our CPU features.

To determine our MMU and CPU features, early_setup() calls functions
(dt_cpu_ftrs_init, early_init_devtree) that call out to generic code
like of_scan_flat_dt. We need to do this before we turn on translations
because we can't set up the MMU until we know what MMU we have.

So this puts us in a bind:

 - We can't set up an early shadow until we have translations on, which
   requires that the MMU is set up.

 - We can't set up an MMU until we call out to generic code for FDT
   parsing.

So there will be calls to generic FDT parsing code that happen before the
early shadow is set up.

The setup code also prints a bunch of information about the platform
with printk() while translations are off, so it wouldn't even be enough
to disable instrumentation for bits of the generic DT code on ppc64.

Does that make sense? If you can figure out how to 'square the circle'
here I'm all ears.

Other notes:

 - There's a comment about printk() being 'safe' in early_setup(), that
   refers to having a valid PACA, it doesn't mean that it's safe in any
   other sense.

 - KVM does indeed also run stuff with translations off but we can catch
   all of that by disabling instrumentation on the real-mode handlers:
   it doesn't seem to leak out to generic code. So you are right that
   KVM is no longer an issue.

Kind regards,
Daniel


>
> Christophe


^ permalink raw reply

* Re: [PATCH v3 25/41] KVM: PPC: Book3S HV P9: Reduce irq_work vs guest decrementer races
From: Alexey Kardashevskiy @ 2021-03-23  1:43 UTC (permalink / raw)
  To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <20210305150638.2675513-26-npiggin@gmail.com>



On 06/03/2021 02:06, Nicholas Piggin wrote:
> irq_work's use of the DEC SPR is racy with guest<->host switch and guest
> entry which flips the DEC interrupt to guest, which could lose a host
> work interrupt.
> 
> This patch closes one race, and attempts to comment another class of
> races.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>   arch/powerpc/kvm/book3s_hv.c | 15 ++++++++++++++-
>   1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 6f3e3aed99aa..b7a88960ac49 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -3704,6 +3704,18 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>   	if (!(vcpu->arch.ctrl & 1))
>   		mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
>   
> +	/*
> +	 * When setting DEC, we must always deal with irq_work_raise via NMI vs
> +	 * setting DEC. The problem occurs right as we switch into guest mode
> +	 * if a NMI hits and sets pending work and sets DEC, then that will
> +	 * apply to the guest and not bring us back to the host.
> +	 *
> +	 * irq_work_raise could check a flag (or possibly LPCR[HDICE] for
> +	 * example) and set HDEC to 1? That wouldn't solve the nested hv
> +	 * case which needs to abort the hcall or zero the time limit.
> +	 *
> +	 * XXX: Another day's problem.
> +	 */
>   	mtspr(SPRN_DEC, vcpu->arch.dec_expires - tb);
>   
>   	if (kvmhv_on_pseries()) {
> @@ -3838,7 +3850,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
>   	vc->entry_exit_map = 0x101;
>   	vc->in_guest = 0;
>   
> -	mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - tb);
> +	set_dec_or_work(local_paca->kvm_hstate.dec_expires - tb);

set_dec_or_work() will write local_paca->kvm_hstate.dec_expires - tb - 1 
to SPRN_DEC which is not exactly the same, is this still alright?


> +
>   	mtspr(SPRN_SPRG_VDSO_WRITE, local_paca->sprg_vdso);
>   
>   	kvmhv_load_host_pmu();
> 

-- 
Alexey

^ permalink raw reply

* Re: [PATCH v6 1/6] KVM: PPC: Book3S HV: Fix comments of H_RPT_INVALIDATE arguments
From: David Gibson @ 2021-03-23  1:19 UTC (permalink / raw)
  To: Bharata B Rao; +Cc: farosas, aneesh.kumar, npiggin, kvm-ppc, linuxppc-dev
In-Reply-To: <20210311083939.595568-2-bharata@linux.ibm.com>

[-- Attachment #1: Type: text/plain, Size: 1761 bytes --]

On Thu, Mar 11, 2021 at 02:09:34PM +0530, Bharata B Rao wrote:
> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
> 
> The type values H_RPTI_TYPE_PRT and H_RPTI_TYPE_PAT indicate
> invalidating the caching of process and partition scoped entries
> respectively.
> 
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>

Not sure the change really clarifies that much, but whatever

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  arch/powerpc/include/asm/hvcall.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
> index ed6086d57b22..6af7bb3c9121 100644
> --- a/arch/powerpc/include/asm/hvcall.h
> +++ b/arch/powerpc/include/asm/hvcall.h
> @@ -411,9 +411,9 @@
>  #define H_RPTI_TYPE_NESTED	0x0001	/* Invalidate nested guest partition-scope */
>  #define H_RPTI_TYPE_TLB		0x0002	/* Invalidate TLB */
>  #define H_RPTI_TYPE_PWC		0x0004	/* Invalidate Page Walk Cache */
> -/* Invalidate Process Table Entries if H_RPTI_TYPE_NESTED is clear */
> +/* Invalidate caching of Process Table Entries if H_RPTI_TYPE_NESTED is clear */
>  #define H_RPTI_TYPE_PRT		0x0008
> -/* Invalidate Partition Table Entries if H_RPTI_TYPE_NESTED is set */
> +/* Invalidate caching of Partition Table Entries if H_RPTI_TYPE_NESTED is set */
>  #define H_RPTI_TYPE_PAT		0x0008
>  #define H_RPTI_TYPE_ALL		(H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC | \
>  				 H_RPTI_TYPE_PRT)

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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* Re: [PATCH v6 2/6] powerpc/book3s64/radix: Add H_RPT_INVALIDATE pgsize encodings to mmu_psize_def
From: David Gibson @ 2021-03-23  1:24 UTC (permalink / raw)
  To: Bharata B Rao; +Cc: farosas, aneesh.kumar, npiggin, kvm-ppc, linuxppc-dev
In-Reply-To: <20210311083939.595568-3-bharata@linux.ibm.com>

[-- Attachment #1: Type: text/plain, Size: 2737 bytes --]

On Thu, Mar 11, 2021 at 02:09:35PM +0530, Bharata B Rao wrote:
> Add a field to mmu_psize_def to store the page size encodings
> of H_RPT_INVALIDATE hcall. Initialize this while scanning the radix
> AP encodings. This will be used when invalidating with required
> page size encoding in the hcall.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>

Having the table be the source of truth and implementing
psize_to_rpti_pgsize() in terms of it would be nicer.  But... I guess
you can't really do that, because you're dynamically initializing the
table from the device tree, but the device tree doesn't include the
RPTI encodings.  Oh well.

Reveiwed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  arch/powerpc/include/asm/book3s/64/mmu.h | 1 +
>  arch/powerpc/mm/book3s64/radix_pgtable.c | 5 +++++
>  2 files changed, 6 insertions(+)
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
> index eace8c3f7b0a..c02f42d1031e 100644
> --- a/arch/powerpc/include/asm/book3s/64/mmu.h
> +++ b/arch/powerpc/include/asm/book3s/64/mmu.h
> @@ -19,6 +19,7 @@ struct mmu_psize_def {
>  	int		penc[MMU_PAGE_COUNT];	/* HPTE encoding */
>  	unsigned int	tlbiel;	/* tlbiel supported for that page size */
>  	unsigned long	avpnm;	/* bits to mask out in AVPN in the HPTE */
> +	unsigned long   h_rpt_pgsize; /* H_RPT_INVALIDATE page size encoding */
>  	union {
>  		unsigned long	sllp;	/* SLB L||LP (exact mask to use in slbmte) */
>  		unsigned long ap;	/* Ap encoding used by PowerISA 3.0 */
> diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
> index 98f0b243c1ab..1b749899016b 100644
> --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
> @@ -486,6 +486,7 @@ static int __init radix_dt_scan_page_sizes(unsigned long node,
>  		def = &mmu_psize_defs[idx];
>  		def->shift = shift;
>  		def->ap  = ap;
> +		def->h_rpt_pgsize = psize_to_rpti_pgsize(idx);
>  	}
>  
>  	/* needed ? */
> @@ -560,9 +561,13 @@ void __init radix__early_init_devtree(void)
>  		 */
>  		mmu_psize_defs[MMU_PAGE_4K].shift = 12;
>  		mmu_psize_defs[MMU_PAGE_4K].ap = 0x0;
> +		mmu_psize_defs[MMU_PAGE_4K].h_rpt_pgsize =
> +			psize_to_rpti_pgsize(MMU_PAGE_4K);
>  
>  		mmu_psize_defs[MMU_PAGE_64K].shift = 16;
>  		mmu_psize_defs[MMU_PAGE_64K].ap = 0x5;
> +		mmu_psize_defs[MMU_PAGE_64K].h_rpt_pgsize =
> +			psize_to_rpti_pgsize(MMU_PAGE_64K);
>  	}
>  
>  	/*

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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* Re: [PATCH v6 6/6] KVM: PPC: Book3S HV: Use H_RPT_INVALIDATE in nested KVM
From: David Gibson @ 2021-03-23  2:35 UTC (permalink / raw)
  To: Bharata B Rao; +Cc: farosas, aneesh.kumar, npiggin, kvm-ppc, linuxppc-dev
In-Reply-To: <20210311083939.595568-7-bharata@linux.ibm.com>

[-- Attachment #1: Type: text/plain, Size: 3909 bytes --]

On Thu, Mar 11, 2021 at 02:09:39PM +0530, Bharata B Rao wrote:
> In the nested KVM case, replace H_TLB_INVALIDATE by the new hcall
> H_RPT_INVALIDATE if available. The availability of this hcall
> is determined from "hcall-rpt-invalidate" string in ibm,hypertas-functions
> DT property.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  arch/powerpc/kvm/book3s_64_mmu_radix.c | 27 +++++++++++++++++++++-----
>  arch/powerpc/kvm/book3s_hv_nested.c    | 12 ++++++++++--
>  2 files changed, 32 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
> index e603de7ade52..1e1e55fd0ee5 100644
> --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
> +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
> @@ -21,6 +21,7 @@
>  #include <asm/pte-walk.h>
>  #include <asm/ultravisor.h>
>  #include <asm/kvm_book3s_uvmem.h>
> +#include <asm/plpar_wrappers.h>
>  
>  /*
>   * Supported radix tree geometry.
> @@ -318,9 +319,19 @@ void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr,
>  	}
>  
>  	psi = shift_to_mmu_psize(pshift);
> -	rb = addr | (mmu_get_ap(psi) << PPC_BITLSHIFT(58));
> -	rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(0, 0, 1),
> -				lpid, rb);
> +
> +	if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE)) {
> +		rb = addr | (mmu_get_ap(psi) << PPC_BITLSHIFT(58));
> +		rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(0, 0, 1),
> +					lpid, rb);
> +	} else {
> +		rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU,
> +					    H_RPTI_TYPE_NESTED |
> +					    H_RPTI_TYPE_TLB,
> +					    psize_to_rpti_pgsize(psi),
> +					    addr, addr + psize);
> +	}
> +
>  	if (rc)
>  		pr_err("KVM: TLB page invalidation hcall failed, rc=%ld\n", rc);
>  }
> @@ -334,8 +345,14 @@ static void kvmppc_radix_flush_pwc(struct kvm *kvm, unsigned int lpid)
>  		return;
>  	}
>  
> -	rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(1, 0, 1),
> -				lpid, TLBIEL_INVAL_SET_LPID);
> +	if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE))
> +		rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(1, 0, 1),
> +					lpid, TLBIEL_INVAL_SET_LPID);
> +	else
> +		rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU,
> +					    H_RPTI_TYPE_NESTED |
> +					    H_RPTI_TYPE_PWC, H_RPTI_PAGE_ALL,
> +					    0, -1UL);
>  	if (rc)
>  		pr_err("KVM: TLB PWC invalidation hcall failed, rc=%ld\n", rc);
>  }
> diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
> index adcc8e26ef22..5601b7eb9b89 100644
> --- a/arch/powerpc/kvm/book3s_hv_nested.c
> +++ b/arch/powerpc/kvm/book3s_hv_nested.c
> @@ -19,6 +19,7 @@
>  #include <asm/pgalloc.h>
>  #include <asm/pte-walk.h>
>  #include <asm/reg.h>
> +#include <asm/plpar_wrappers.h>
>  
>  static struct patb_entry *pseries_partition_tb;
>  
> @@ -444,8 +445,15 @@ static void kvmhv_flush_lpid(unsigned int lpid)
>  		return;
>  	}
>  
> -	rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
> -				lpid, TLBIEL_INVAL_SET_LPID);
> +	if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE))
> +		rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
> +					lpid, TLBIEL_INVAL_SET_LPID);
> +	else
> +		rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU,
> +					    H_RPTI_TYPE_NESTED |
> +					    H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
> +					    H_RPTI_TYPE_PAT,
> +					    H_RPTI_PAGE_ALL, 0, -1UL);
>  	if (rc)
>  		pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc);
>  }

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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* Re: [PATCH v6 4/6] KVM: PPC: Book3S HV: Nested support in H_RPT_INVALIDATE
From: David Gibson @ 2021-03-23  2:33 UTC (permalink / raw)
  To: Bharata B Rao; +Cc: farosas, aneesh.kumar, npiggin, kvm-ppc, linuxppc-dev
In-Reply-To: <20210311083939.595568-5-bharata@linux.ibm.com>

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On Thu, Mar 11, 2021 at 02:09:37PM +0530, Bharata B Rao wrote:
> Enable support for process-scoped invalidations from nested
> guests and partition-scoped invalidations for nested guests.
> 
> Process-scoped invalidations for any level of nested guests
> are handled by implementing H_RPT_INVALIDATE handler in the
> nested guest exit path in L0.
> 
> Partition-scoped invalidation requests are forwarded to the
> right nested guest, handled there and passed down to L0
> for eventual handling.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> 	[Nested guest partition-scoped invalidation changes]

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  arch/powerpc/include/asm/kvm_book3s.h |   3 +
>  arch/powerpc/kvm/book3s_hv.c          |  71 +++++++++++++++++-
>  arch/powerpc/kvm/book3s_hv_nested.c   | 104 ++++++++++++++++++++++++++
>  3 files changed, 175 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
> index 2f5f919f6cd3..de8fc5a4d19c 100644
> --- a/arch/powerpc/include/asm/kvm_book3s.h
> +++ b/arch/powerpc/include/asm/kvm_book3s.h
> @@ -305,6 +305,9 @@ void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1);
>  void kvmhv_release_all_nested(struct kvm *kvm);
>  long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu);
>  long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu);
> +long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
> +			     unsigned long type, unsigned long pg_sizes,
> +			     unsigned long start, unsigned long end);
>  int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu,
>  			  u64 time_limit, unsigned long lpcr);
>  void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr);
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 5d008468347c..03755389efd1 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -922,6 +922,46 @@ static int kvmppc_get_yield_count(struct kvm_vcpu *vcpu)
>  	return yield_count;
>  }
>  
> +/*
> + * H_RPT_INVALIDATE hcall handler for nested guests.
> + *
> + * Handles only nested process-scoped invalidation requests in L0.
> + */
> +static int kvmppc_nested_h_rpt_invalidate(struct kvm_vcpu *vcpu)
> +{
> +	unsigned long type = kvmppc_get_gpr(vcpu, 6);
> +	unsigned long pid, pg_sizes, start, end, psize;
> +	struct kvm_nested_guest *gp;
> +	struct mmu_psize_def *def;
> +
> +	/*
> +	 * The partition-scoped invalidations aren't handled here in L0.
> +	 */
> +	if (type & H_RPTI_TYPE_NESTED)
> +		return RESUME_HOST;
> +
> +	pid = kvmppc_get_gpr(vcpu, 4);
> +	pg_sizes = kvmppc_get_gpr(vcpu, 7);
> +	start = kvmppc_get_gpr(vcpu, 8);
> +	end = kvmppc_get_gpr(vcpu, 9);
> +
> +	gp = kvmhv_get_nested(vcpu->kvm, vcpu->kvm->arch.lpid, false);
> +	if (!gp)
> +		goto out;
> +
> +	for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
> +		def = &mmu_psize_defs[psize];
> +		if (pg_sizes & def->h_rpt_pgsize)
> +			do_h_rpt_invalidate_prt(pid, gp->shadow_lpid, type,
> +						(1UL << def->shift), psize,
> +						start, end);
> +	}
> +	kvmhv_put_nested(gp);
> +out:
> +	kvmppc_set_gpr(vcpu, 3, H_SUCCESS);
> +	return RESUME_GUEST;
> +}
> +
>  static long kvmppc_h_rpt_invalidate(struct kvm_vcpu *vcpu,
>  				    unsigned long id, unsigned long target,
>  				    unsigned long type, unsigned long pg_sizes,
> @@ -938,10 +978,18 @@ static long kvmppc_h_rpt_invalidate(struct kvm_vcpu *vcpu,
>  
>  	/*
>  	 * Partition-scoped invalidation for nested guests.
> -	 * Not yet supported
>  	 */
> -	if (type & H_RPTI_TYPE_NESTED)
> -		return H_P3;
> +	if (type & H_RPTI_TYPE_NESTED) {
> +		if (!nesting_enabled(vcpu->kvm))
> +			return H_FUNCTION;
> +
> +		/* Support only cores as target */
> +		if (target != H_RPTI_TARGET_CMMU)
> +			return H_P2;
> +
> +		return do_h_rpt_invalidate_pat(vcpu, id, type, pg_sizes,
> +					       start, end);
> +	}
>  
>  	/*
>  	 * Process-scoped invalidation for L1 guests.
> @@ -1636,6 +1684,23 @@ static int kvmppc_handle_nested_exit(struct kvm_vcpu *vcpu)
>  		if (!xics_on_xive())
>  			kvmppc_xics_rm_complete(vcpu, 0);
>  		break;
> +	case BOOK3S_INTERRUPT_SYSCALL:
> +	{
> +		unsigned long req = kvmppc_get_gpr(vcpu, 3);
> +
> +		/*
> +		 * The H_RPT_INVALIDATE hcalls issued by nested
> +		 * guests for process-scoped invalidations when
> +		 * GTSE=0, are handled here in L0.
> +		 */
> +		if (req == H_RPT_INVALIDATE) {
> +			r = kvmppc_nested_h_rpt_invalidate(vcpu);
> +			break;
> +		}
> +
> +		r = RESUME_HOST;
> +		break;
> +	}
>  	default:
>  		r = RESUME_HOST;
>  		break;
> diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
> index 0cd0e7aad588..adcc8e26ef22 100644
> --- a/arch/powerpc/kvm/book3s_hv_nested.c
> +++ b/arch/powerpc/kvm/book3s_hv_nested.c
> @@ -1191,6 +1191,110 @@ long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu)
>  	return H_SUCCESS;
>  }
>  
> +static long do_tlb_invalidate_nested_tlb(struct kvm_vcpu *vcpu,
> +					 unsigned long lpid,
> +					 unsigned long page_size,
> +					 unsigned long ap,
> +					 unsigned long start,
> +					 unsigned long end)
> +{
> +	unsigned long addr = start;
> +	int ret;
> +
> +	do {
> +		ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap,
> +						   get_epn(addr));
> +		if (ret)
> +			return ret;
> +		addr += page_size;
> +	} while (addr < end);
> +
> +	return ret;
> +}
> +
> +static long do_tlb_invalidate_nested_all(struct kvm_vcpu *vcpu,
> +					 unsigned long lpid, unsigned long ric)
> +{
> +	struct kvm *kvm = vcpu->kvm;
> +	struct kvm_nested_guest *gp;
> +
> +	gp = kvmhv_get_nested(kvm, lpid, false);
> +	if (gp) {
> +		kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
> +		kvmhv_put_nested(gp);
> +	}
> +	return H_SUCCESS;
> +}
> +
> +/*
> + * Performs partition-scoped invalidations for nested guests
> + * as part of H_RPT_INVALIDATE hcall.
> + */
> +long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
> +			     unsigned long type, unsigned long pg_sizes,
> +			     unsigned long start, unsigned long end)
> +{
> +	struct kvm_nested_guest *gp;
> +	long ret;
> +	unsigned long psize, ap;
> +
> +	/*
> +	 * If L2 lpid isn't valid, we need to return H_PARAMETER.
> +	 *
> +	 * However, nested KVM issues a L2 lpid flush call when creating
> +	 * partition table entries for L2. This happens even before the
> +	 * corresponding shadow lpid is created in HV which happens in
> +	 * H_ENTER_NESTED call. Since we can't differentiate this case from
> +	 * the invalid case, we ignore such flush requests and return success.
> +	 */
> +	gp = kvmhv_find_nested(vcpu->kvm, lpid);
> +	if (!gp)
> +		return H_SUCCESS;
> +
> +	/*
> +	 * A flush all request can be handled by a full lpid flush only.
> +	 */
> +	if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
> +		return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_ALL);
> +
> +#if 0
> +	/*
> +	 * We don't need to handle a PWC flush like process table here,
> +	 * because intermediate partition scoped table in nested guest doesn't
> +	 * really have PWC. Only level we have PWC is in L0 and for nested
> +	 * invalidate at L0 we always do kvm_flush_lpid() which does
> +	 * radix__flush_all_lpid(). For range invalidate at any level, we
> +	 * are not removing the higher level page tables and hence there is
> +	 * no PWC invalidate needed.
> +	 */
> +	if (type & H_RPTI_TYPE_PWC) {
> +		ret = do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_PWC);
> +		if (ret)
> +			return H_P4;
> +	}
> +#endif
> +
> +	if (start == 0 && end == -1)
> +		return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_TLB);
> +
> +	if (type & H_RPTI_TYPE_TLB) {
> +		struct mmu_psize_def *def;
> +
> +		for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
> +			def = &mmu_psize_defs[psize];
> +			if (!(pg_sizes & def->h_rpt_pgsize))
> +				continue;
> +
> +			ret = do_tlb_invalidate_nested_tlb(vcpu, lpid,
> +							   (1UL << def->shift),
> +							   ap, start, end);
> +			if (ret)
> +				return H_P4;
> +		}
> +	}
> +	return H_SUCCESS;
> +}
> +
>  /* Used to convert a nested guest real address to a L1 guest real address */
>  static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
>  				       struct kvm_nested_guest *gp,

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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