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* [PULL 24/50] arm64: KVM: Inject a Virtual SError if it was pending
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

If we have caught an SError whilst exiting, we've tagged the
exit code with the pending information. In that case, let's
re-inject the error into the guest, after having adjusted
the PC if required.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/handle_exit.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 08afc69a..a204adf 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -170,6 +170,26 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
 {
 	exit_handle_fn exit_handler;
 
+	if (ARM_SERROR_PENDING(exception_index)) {
+		u8 hsr_ec = ESR_ELx_EC(kvm_vcpu_get_hsr(vcpu));
+
+		/*
+		 * HVC/SMC already have an adjusted PC, which we need
+		 * to correct in order to return to after having
+		 * injected the SError.
+		 */
+		if (hsr_ec == ESR_ELx_EC_HVC32 || hsr_ec == ESR_ELx_EC_HVC64 ||
+		    hsr_ec == ESR_ELx_EC_SMC32 || hsr_ec == ESR_ELx_EC_SMC64) {
+			u32 adj =  kvm_vcpu_trap_il_is32bit(vcpu) ? 4 : 2;
+			*vcpu_pc(vcpu) -= adj;
+		}
+
+		kvm_inject_vabt(vcpu);
+		return 1;
+	}
+
+	exception_index = ARM_EXCEPTION_CODE(exception_index);
+
 	switch (exception_index) {
 	case ARM_EXCEPTION_IRQ:
 		return 1;
-- 
2.9.0

^ permalink raw reply related

* [PULL 23/50] arm64: KVM: Allow an exit code to be tagged with an SError
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

Similarily to EL1, an asynchronous abort can be triggered whilst
running at EL2. But instead of making that a new error code,
we need to communicate it to the rest of KVM together with
the exit reason. So let's hijack a single bit that allows the
exception code to be tagged with a "pending SError" information.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_asm.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index d177e7e..18f7465 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -20,6 +20,10 @@
 
 #include <asm/virt.h>
 
+#define ARM_EXIT_WITH_SERROR_BIT  31
+#define ARM_EXCEPTION_CODE(x)	  ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT))
+#define ARM_SERROR_PENDING(x)	  !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT))
+
 #define ARM_EXCEPTION_IRQ	  0
 #define ARM_EXCEPTION_EL1_SERROR  1
 #define ARM_EXCEPTION_TRAP	  2
-- 
2.9.0

^ permalink raw reply related

* [PULL 22/50] arm64: KVM: Route asynchronous aborts
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

As we now have some basic handling to EL1-triggered aborts, we can
actually report them to KVM.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/hyp/hyp-entry.S | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index d6cae54..d2f6640 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -120,6 +120,12 @@ el1_irq:
 	mov	x0, #ARM_EXCEPTION_IRQ
 	b	__guest_exit
 
+el1_error:
+	stp     x0, x1, [sp, #-16]!
+	mrs	x1, tpidr_el2
+	mov	x0, #ARM_EXCEPTION_EL1_SERROR
+	b	__guest_exit
+
 ENTRY(__hyp_do_panic)
 	mov	lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\
 		      PSR_MODE_EL1h)
@@ -148,7 +154,6 @@ ENDPROC(\label)
 	invalid_vector	el1_sync_invalid
 	invalid_vector	el1_irq_invalid
 	invalid_vector	el1_fiq_invalid
-	invalid_vector	el1_error_invalid
 
 	.ltorg
 
@@ -168,10 +173,10 @@ ENTRY(__kvm_hyp_vector)
 	ventry	el1_sync			// Synchronous 64-bit EL1
 	ventry	el1_irq				// IRQ 64-bit EL1
 	ventry	el1_fiq_invalid			// FIQ 64-bit EL1
-	ventry	el1_error_invalid		// Error 64-bit EL1
+	ventry	el1_error			// Error 64-bit EL1
 
 	ventry	el1_sync			// Synchronous 32-bit EL1
 	ventry	el1_irq				// IRQ 32-bit EL1
 	ventry	el1_fiq_invalid			// FIQ 32-bit EL1
-	ventry	el1_error_invalid		// Error 32-bit EL1
+	ventry	el1_error			// Error 32-bit EL1
 ENDPROC(__kvm_hyp_vector)
-- 
2.9.0

^ permalink raw reply related

* [PULL 21/50] arm64: KVM: Add EL1 async abort handler
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

If we've exited the guest because it has triggered an asynchronous
abort from EL1, a possible course of action is to let it know it
screwed up by giving it a Virtual Abort to chew on.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/handle_exit.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index fa96fe2..08afc69a 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -173,6 +173,9 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
 	switch (exception_index) {
 	case ARM_EXCEPTION_IRQ:
 		return 1;
+	case ARM_EXCEPTION_EL1_SERROR:
+		kvm_inject_vabt(vcpu);
+		return 1;
 	case ARM_EXCEPTION_TRAP:
 		/*
 		 * See ARM ARM B1.14.1: "Hyp traps on instructions
-- 
2.9.0

^ permalink raw reply related

* [PULL 20/50] arm64: KVM: Add exception code to report EL1 asynchronous aborts
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

So far, we don't have a code to indicate that we've taken an
asynchronous abort from EL1. Let's add one.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_asm.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 7561f63..d177e7e 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -21,9 +21,10 @@
 #include <asm/virt.h>
 
 #define ARM_EXCEPTION_IRQ	  0
-#define ARM_EXCEPTION_TRAP	  1
+#define ARM_EXCEPTION_EL1_SERROR  1
+#define ARM_EXCEPTION_TRAP	  2
 /* The hyp-stub will return this for any kvm_call_hyp() call */
-#define ARM_EXCEPTION_HYP_GONE	  2
+#define ARM_EXCEPTION_HYP_GONE	  3
 
 #define KVM_ARM64_DEBUG_DIRTY_SHIFT	0
 #define KVM_ARM64_DEBUG_DIRTY		(1 << KVM_ARM64_DEBUG_DIRTY_SHIFT)
-- 
2.9.0

^ permalink raw reply related

* [PULL 19/50] arm64: KVM: Add Virtual Abort injection helper
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

Now that we're able to context switch the HCR_EL2.VA bit, let's
introduce a helper that injects an Abort into a vcpu.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_emulate.h |  1 +
 arch/arm64/kvm/inject_fault.c        | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index b336434d..fd9d5fd 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -38,6 +38,7 @@ bool kvm_condition_valid32(const struct kvm_vcpu *vcpu);
 void kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr);
 
 void kvm_inject_undefined(struct kvm_vcpu *vcpu);
+void kvm_inject_vabt(struct kvm_vcpu *vcpu);
 void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
 void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
 
diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c
index 898c0e6..da6a8cf 100644
--- a/arch/arm64/kvm/inject_fault.c
+++ b/arch/arm64/kvm/inject_fault.c
@@ -231,3 +231,15 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu)
 	else
 		inject_undef64(vcpu);
 }
+
+/**
+ * kvm_inject_vabt - inject an async abort / SError into the guest
+ * @vcpu: The VCPU to receive the exception
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ */
+void kvm_inject_vabt(struct kvm_vcpu *vcpu)
+{
+	vcpu_set_hcr(vcpu, vcpu_get_hcr(vcpu) | HCR_VSE);
+}
-- 
2.9.0

^ permalink raw reply related

* [PULL 18/50] arm64: KVM: Preserve pending vSError in world switch
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

The HCR_EL2.VSE bit is used to signal an SError to a guest, and has
the peculiar feature of getting cleared when the guest has taken
the abort (this is the only bit that behaves as such in this register).

This means that if we signal such an abort, we must leave it
in the guest context until it disappears from HCR_EL2, and at which
point it must be cleared from the context. This is achieved by
reading back from HCR_EL2 until the guest takes the fault.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/hyp/switch.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index b3a66c5..8246de2 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -110,6 +110,15 @@ static hyp_alternate_select(__deactivate_traps_arch,
 
 static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu)
 {
+	/*
+	 * If we pended a virtual abort, preserve it until it gets
+	 * cleared. See D1.14.3 (Virtual Interrupts) for details, but
+	 * the crucial bit is "On taking a vSError interrupt,
+	 * HCR_EL2.VSE is cleared to 0."
+	 */
+	if (vcpu->arch.hcr_el2 & HCR_VSE)
+		vcpu->arch.hcr_el2 = read_sysreg(hcr_el2);
+
 	__deactivate_traps_arch()();
 	write_sysreg(0, hstr_el2);
 	write_sysreg(read_sysreg(mdcr_el2) & MDCR_EL2_HPMN_MASK, mdcr_el2);
-- 
2.9.0

^ permalink raw reply related

* [PULL 17/50] arm64: KVM: Rename HCR_VA to HCR_VSE
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

HCR_VA is a leftover from ARMv7, On ARMv8, this is HCR_VSE
(which stands for Virtual System Error), and has better
defined semantics.

Let's rename the constant.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_arm.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index 4b5c977..2a2752b 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -50,7 +50,7 @@
 #define HCR_BSU		(3 << 10)
 #define HCR_BSU_IS	(UL(1) << 10)
 #define HCR_FB		(UL(1) << 9)
-#define HCR_VA		(UL(1) << 8)
+#define HCR_VSE		(UL(1) << 8)
 #define HCR_VI		(UL(1) << 7)
 #define HCR_VF		(UL(1) << 6)
 #define HCR_AMO		(UL(1) << 5)
@@ -80,7 +80,7 @@
 #define HCR_GUEST_FLAGS (HCR_TSC | HCR_TSW | HCR_TWE | HCR_TWI | HCR_VM | \
 			 HCR_TVM | HCR_BSU_IS | HCR_FB | HCR_TAC | \
 			 HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW)
-#define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF)
+#define HCR_VIRT_EXCP_MASK (HCR_VSE | HCR_VI | HCR_VF)
 #define HCR_INT_OVERRIDE   (HCR_FMO | HCR_IMO)
 #define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H)
 
-- 
2.9.0

^ permalink raw reply related

* [PULL 16/50] arm64: KVM: vgic-v2: Enable GICV access from HYP if access from guest is unsafe
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

So far, we've been disabling KVM on systems where the GICV region couldn't
be safely given to a guest. Now that we're able to handle this access
safely by emulating it in HYP, we can enable this feature when we detect
an unsafe configuration.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-v2.c | 69 +++++++++++++++++++++++++++------------------
 1 file changed, 42 insertions(+), 27 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
index b8da901..0a063af 100644
--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -278,12 +278,14 @@ int vgic_v2_map_resources(struct kvm *kvm)
 		goto out;
 	}
 
-	ret = kvm_phys_addr_ioremap(kvm, dist->vgic_cpu_base,
-				    kvm_vgic_global_state.vcpu_base,
-				    KVM_VGIC_V2_CPU_SIZE, true);
-	if (ret) {
-		kvm_err("Unable to remap VGIC CPU to VCPU\n");
-		goto out;
+	if (!static_branch_unlikely(&vgic_v2_cpuif_trap)) {
+		ret = kvm_phys_addr_ioremap(kvm, dist->vgic_cpu_base,
+					    kvm_vgic_global_state.vcpu_base,
+					    KVM_VGIC_V2_CPU_SIZE, true);
+		if (ret) {
+			kvm_err("Unable to remap VGIC CPU to VCPU\n");
+			goto out;
+		}
 	}
 
 	dist->ready = true;
@@ -312,45 +314,51 @@ int vgic_v2_probe(const struct gic_kvm_info *info)
 		return -ENXIO;
 	}
 
-	if (!PAGE_ALIGNED(info->vcpu.start)) {
-		kvm_err("GICV physical address 0x%llx not page aligned\n",
-			(unsigned long long)info->vcpu.start);
-		return -ENXIO;
-	}
+	if (!PAGE_ALIGNED(info->vcpu.start) ||
+	    !PAGE_ALIGNED(resource_size(&info->vcpu))) {
+		kvm_info("GICV region size/alignment is unsafe, using trapping (reduced performance)\n");
+		kvm_vgic_global_state.vcpu_base_va = ioremap(info->vcpu.start,
+							     resource_size(&info->vcpu));
+		if (!kvm_vgic_global_state.vcpu_base_va) {
+			kvm_err("Cannot ioremap GICV\n");
+			return -ENOMEM;
+		}
 
-	if (!PAGE_ALIGNED(resource_size(&info->vcpu))) {
-		kvm_err("GICV size 0x%llx not a multiple of page size 0x%lx\n",
-			(unsigned long long)resource_size(&info->vcpu),
-			PAGE_SIZE);
-		return -ENXIO;
+		ret = create_hyp_io_mappings(kvm_vgic_global_state.vcpu_base_va,
+					     kvm_vgic_global_state.vcpu_base_va + resource_size(&info->vcpu),
+					     info->vcpu.start);
+		if (ret) {
+			kvm_err("Cannot map GICV into hyp\n");
+			goto out;
+		}
+
+		static_branch_enable(&vgic_v2_cpuif_trap);
 	}
 
 	kvm_vgic_global_state.vctrl_base = ioremap(info->vctrl.start,
 						   resource_size(&info->vctrl));
 	if (!kvm_vgic_global_state.vctrl_base) {
 		kvm_err("Cannot ioremap GICH\n");
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto out;
 	}
 
 	vtr = readl_relaxed(kvm_vgic_global_state.vctrl_base + GICH_VTR);
 	kvm_vgic_global_state.nr_lr = (vtr & 0x3f) + 1;
 
-	ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
-	if (ret) {
-		kvm_err("Cannot register GICv2 KVM device\n");
-		iounmap(kvm_vgic_global_state.vctrl_base);
-		return ret;
-	}
-
 	ret = create_hyp_io_mappings(kvm_vgic_global_state.vctrl_base,
 				     kvm_vgic_global_state.vctrl_base +
 					 resource_size(&info->vctrl),
 				     info->vctrl.start);
 	if (ret) {
 		kvm_err("Cannot map VCTRL into hyp\n");
-		kvm_unregister_device_ops(KVM_DEV_TYPE_ARM_VGIC_V2);
-		iounmap(kvm_vgic_global_state.vctrl_base);
-		return ret;
+		goto out;
+	}
+
+	ret = kvm_register_vgic_device(KVM_DEV_TYPE_ARM_VGIC_V2);
+	if (ret) {
+		kvm_err("Cannot register GICv2 KVM device\n");
+		goto out;
 	}
 
 	kvm_vgic_global_state.can_emulate_gicv2 = true;
@@ -361,4 +369,11 @@ int vgic_v2_probe(const struct gic_kvm_info *info)
 	kvm_info("vgic-v2@%llx\n", info->vctrl.start);
 
 	return 0;
+out:
+	if (kvm_vgic_global_state.vctrl_base)
+		iounmap(kvm_vgic_global_state.vctrl_base);
+	if (kvm_vgic_global_state.vcpu_base_va)
+		iounmap(kvm_vgic_global_state.vcpu_base_va);
+
+	return ret;
 }
-- 
2.9.0

^ permalink raw reply related

* [PULL 15/50] arm64: KVM: vgic-v2: Add GICV access from HYP
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

Now that we have the necessary infrastructure to handle MMIO accesses
in HYP, perform the GICV access on behalf of the guest. This requires
checking that the access is strictly 32bit, properly aligned, and
falls within the expected range.

When all condition are satisfied, we perform the access and tell
the rest of the HYP code that the instruction has been correctly
emulated.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 include/kvm/arm_vgic.h        |  3 +++
 virt/kvm/arm/hyp/vgic-v2-sr.c | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 8eb1501..bb46c03 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -50,6 +50,9 @@ struct vgic_global {
 	/* Physical address of vgic virtual cpu interface */
 	phys_addr_t		vcpu_base;
 
+	/* GICV mapping */
+	void __iomem		*vcpu_base_va;
+
 	/* virtual control interface mapping */
 	void __iomem		*vctrl_base;
 
diff --git a/virt/kvm/arm/hyp/vgic-v2-sr.c b/virt/kvm/arm/hyp/vgic-v2-sr.c
index 3e2a62e..a052f20 100644
--- a/virt/kvm/arm/hyp/vgic-v2-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v2-sr.c
@@ -19,6 +19,7 @@
 #include <linux/irqchip/arm-gic.h>
 #include <linux/kvm_host.h>
 
+#include <asm/kvm_emulate.h>
 #include <asm/kvm_hyp.h>
 
 static void __hyp_text save_maint_int_state(struct kvm_vcpu *vcpu,
@@ -171,6 +172,44 @@ void __hyp_text __vgic_v2_restore_state(struct kvm_vcpu *vcpu)
 #ifdef CONFIG_ARM64
 bool __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
 {
+	struct kvm *kvm = kern_hyp_va(vcpu->kvm);
+	struct vgic_dist *vgic = &kvm->arch.vgic;
+	phys_addr_t fault_ipa;
+	void __iomem *addr;
+	int rd;
+
+	/* Build the full address */
+	fault_ipa  = kvm_vcpu_get_fault_ipa(vcpu);
+	fault_ipa |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0);
+
+	/* If not for GICV, move on */
+	if (fault_ipa <  vgic->vgic_cpu_base ||
+	    fault_ipa >= (vgic->vgic_cpu_base + KVM_VGIC_V2_CPU_SIZE))
 		return false;
+
+	/* Reject anything but a 32bit access */
+	if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32))
+		return false;
+
+	/* Not aligned? Don't bother */
+	if (fault_ipa & 3)
+		return false;
+
+	rd = kvm_vcpu_dabt_get_rd(vcpu);
+	addr  = kern_hyp_va((kern_hyp_va(&kvm_vgic_global_state))->vcpu_base_va);
+	addr += fault_ipa - vgic->vgic_cpu_base;
+
+	if (kvm_vcpu_dabt_iswrite(vcpu)) {
+		u32 data = vcpu_data_guest_to_host(vcpu,
+						   vcpu_get_reg(vcpu, rd),
+						   sizeof(u32));
+		writel_relaxed(data, addr);
+	} else {
+		u32 data = readl_relaxed(addr);
+		vcpu_set_reg(vcpu, rd, vcpu_data_host_to_guest(vcpu, data,
+							       sizeof(u32)));
+	}
+
+	return true;
 }
 #endif
-- 
2.9.0

^ permalink raw reply related

* [PULL 14/50] arm64: KVM: vgic-v2: Add the GICV emulation infrastructure
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

In order to efficiently perform the GICV access on behalf of the
guest, we need to be able to avoid going back all the way to
the host kernel.

For this, we introduce a new hook in the world switch code,
conveniently placed just after populating the fault info.
At that point, we only have saved/restored the GP registers,
and we can quickly perform all the required checks (data abort,
translation fault, valid faulting syndrome, not an external
abort, not a PTW).

Coming back from the emulation code, we need to skip the emulated
instruction. This involves an additional bit of save/restore in
order to be able to access the guest's PC (and possibly CPSR if
this is a 32bit guest).

At this stage, no emulation code is provided.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_hyp.h |  1 +
 arch/arm64/kvm/hyp/switch.c      | 32 ++++++++++++++++++++++++++++++++
 include/kvm/arm_vgic.h           |  3 +++
 virt/kvm/arm/hyp/vgic-v2-sr.c    |  7 +++++++
 virt/kvm/arm/vgic/vgic-v2.c      |  2 ++
 5 files changed, 45 insertions(+)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index cff5105..88ec3ac 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -123,6 +123,7 @@ typeof(orig) * __hyp_text fname(void)					\
 
 void __vgic_v2_save_state(struct kvm_vcpu *vcpu);
 void __vgic_v2_restore_state(struct kvm_vcpu *vcpu);
+bool __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu);
 
 void __vgic_v3_save_state(struct kvm_vcpu *vcpu);
 void __vgic_v3_restore_state(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 35d2e09..b3a66c5 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -17,6 +17,7 @@
 
 #include <linux/types.h>
 #include <asm/kvm_asm.h>
+#include <asm/kvm_emulate.h>
 #include <asm/kvm_hyp.h>
 
 static bool __hyp_text __fpsimd_enabled_nvhe(void)
@@ -232,6 +233,21 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
 	return true;
 }
 
+static void __hyp_text __skip_instr(struct kvm_vcpu *vcpu)
+{
+	*vcpu_pc(vcpu) = read_sysreg_el2(elr);
+
+	if (vcpu_mode_is_32bit(vcpu)) {
+		vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(spsr);
+		kvm_skip_instr32(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+		write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, spsr);
+	} else {
+		*vcpu_pc(vcpu) += 4;
+	}
+
+	write_sysreg_el2(*vcpu_pc(vcpu), elr);
+}
+
 int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpu_context *host_ctxt;
@@ -270,6 +286,22 @@ again:
 	if (exit_code == ARM_EXCEPTION_TRAP && !__populate_fault_info(vcpu))
 		goto again;
 
+	if (static_branch_unlikely(&vgic_v2_cpuif_trap) &&
+	    exit_code == ARM_EXCEPTION_TRAP) {
+		bool valid;
+
+		valid = kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_DABT_LOW &&
+			kvm_vcpu_trap_get_fault_type(vcpu) == FSC_FAULT &&
+			kvm_vcpu_dabt_isvalid(vcpu) &&
+			!kvm_vcpu_dabt_isextabt(vcpu) &&
+			!kvm_vcpu_dabt_iss1tw(vcpu);
+
+		if (valid && __vgic_v2_perform_cpuif_access(vcpu)) {
+			__skip_instr(vcpu);
+			goto again;
+		}
+	}
+
 	fp_enabled = __fpsimd_enabled();
 
 	__sysreg_save_guest_state(guest_ctxt);
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 19b698e..8eb1501 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -20,6 +20,7 @@
 #include <linux/kvm.h>
 #include <linux/irqreturn.h>
 #include <linux/spinlock.h>
+#include <linux/static_key.h>
 #include <linux/types.h>
 #include <kvm/iodev.h>
 #include <linux/list.h>
@@ -265,6 +266,8 @@ struct vgic_cpu {
 	bool lpis_enabled;
 };
 
+extern struct static_key_false vgic_v2_cpuif_trap;
+
 int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write);
 void kvm_vgic_early_init(struct kvm *kvm);
 int kvm_vgic_create(struct kvm *kvm, u32 type);
diff --git a/virt/kvm/arm/hyp/vgic-v2-sr.c b/virt/kvm/arm/hyp/vgic-v2-sr.c
index 7cffd93..3e2a62e 100644
--- a/virt/kvm/arm/hyp/vgic-v2-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v2-sr.c
@@ -167,3 +167,10 @@ void __hyp_text __vgic_v2_restore_state(struct kvm_vcpu *vcpu)
 	writel_relaxed(cpu_if->vgic_vmcr, base + GICH_VMCR);
 	vcpu->arch.vgic_cpu.live_lrs = live_lrs;
 }
+
+#ifdef CONFIG_ARM64
+bool __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
+{
+		return false;
+}
+#endif
diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
index 0bf6709..b8da901 100644
--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -294,6 +294,8 @@ out:
 	return ret;
 }
 
+DEFINE_STATIC_KEY_FALSE(vgic_v2_cpuif_trap);
+
 /**
  * vgic_v2_probe - probe for a GICv2 compatible interrupt controller in DT
  * @node:	pointer to the DT node
-- 
2.9.0

^ permalink raw reply related

* [PULL 13/50] arm64: KVM: Make kvm_skip_instr32 available to HYP
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

As we plan to do some emulation at HYP, let's make kvm_skip_instr32
as part of the hyp_text section. This doesn't preclude the kernel
from using it.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/aarch32.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/aarch32.c b/virt/kvm/arm/aarch32.c
index ba4417b..528af4b 100644
--- a/virt/kvm/arm/aarch32.c
+++ b/virt/kvm/arm/aarch32.c
@@ -23,6 +23,7 @@
 
 #include <linux/kvm_host.h>
 #include <asm/kvm_emulate.h>
+#include <asm/kvm_hyp.h>
 
 #ifndef CONFIG_ARM64
 #define COMPAT_PSR_T_BIT	PSR_T_BIT
@@ -108,7 +109,7 @@ bool kvm_condition_valid32(const struct kvm_vcpu *vcpu)
  *
  * IT[7:0] -> CPSR[26:25],CPSR[15:10]
  */
-static void kvm_adjust_itstate(struct kvm_vcpu *vcpu)
+static void __hyp_text kvm_adjust_itstate(struct kvm_vcpu *vcpu)
 {
 	unsigned long itbits, cond;
 	unsigned long cpsr = *vcpu_cpsr(vcpu);
@@ -138,7 +139,7 @@ static void kvm_adjust_itstate(struct kvm_vcpu *vcpu)
  * kvm_skip_instr - skip a trapped instruction and proceed to the next
  * @vcpu: The vcpu pointer
  */
-void kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr)
+void __hyp_text kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr)
 {
 	bool is_thumb;
 
-- 
2.9.0

^ permalink raw reply related

* [PULL 12/50] arm: KVM: Use common AArch32 conditional execution code
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

Add the bit of glue and const-ification that is required to use
the code inherited from the arm64 port, and move over to it.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/include/asm/kvm_emulate.h | 34 ++++++++++---
 arch/arm/kvm/Makefile              |  1 +
 arch/arm/kvm/emulate.c             | 97 --------------------------------------
 virt/kvm/arm/aarch32.c             |  5 ++
 4 files changed, 33 insertions(+), 104 deletions(-)

diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h
index ee5328f..448d63c 100644
--- a/arch/arm/include/asm/kvm_emulate.h
+++ b/arch/arm/include/asm/kvm_emulate.h
@@ -40,18 +40,28 @@ static inline void vcpu_set_reg(struct kvm_vcpu *vcpu, u8 reg_num,
 	*vcpu_reg(vcpu, reg_num) = val;
 }
 
-bool kvm_condition_valid(struct kvm_vcpu *vcpu);
-void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr);
+bool kvm_condition_valid32(const struct kvm_vcpu *vcpu);
+void kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr);
 void kvm_inject_undefined(struct kvm_vcpu *vcpu);
 void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
 void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
 
+static inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
+{
+	return kvm_condition_valid32(vcpu);
+}
+
+static inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
+{
+	kvm_skip_instr32(vcpu, is_wide_instr);
+}
+
 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
 {
 	vcpu->arch.hcr = HCR_GUEST_MASK;
 }
 
-static inline unsigned long vcpu_get_hcr(struct kvm_vcpu *vcpu)
+static inline unsigned long vcpu_get_hcr(const struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.hcr;
 }
@@ -61,7 +71,7 @@ static inline void vcpu_set_hcr(struct kvm_vcpu *vcpu, unsigned long hcr)
 	vcpu->arch.hcr = hcr;
 }
 
-static inline bool vcpu_mode_is_32bit(struct kvm_vcpu *vcpu)
+static inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu)
 {
 	return 1;
 }
@@ -71,9 +81,9 @@ static inline unsigned long *vcpu_pc(struct kvm_vcpu *vcpu)
 	return &vcpu->arch.ctxt.gp_regs.usr_regs.ARM_pc;
 }
 
-static inline unsigned long *vcpu_cpsr(struct kvm_vcpu *vcpu)
+static inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
 {
-	return &vcpu->arch.ctxt.gp_regs.usr_regs.ARM_cpsr;
+	return (unsigned long *)&vcpu->arch.ctxt.gp_regs.usr_regs.ARM_cpsr;
 }
 
 static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
@@ -93,11 +103,21 @@ static inline bool vcpu_mode_priv(struct kvm_vcpu *vcpu)
 	return cpsr_mode > USR_MODE;;
 }
 
-static inline u32 kvm_vcpu_get_hsr(struct kvm_vcpu *vcpu)
+static inline u32 kvm_vcpu_get_hsr(const struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.fault.hsr;
 }
 
+static inline int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu)
+{
+	u32 hsr = kvm_vcpu_get_hsr(vcpu);
+
+	if (hsr & HSR_CV)
+		return (hsr & HSR_COND) >> HSR_COND_SHIFT;
+
+	return -1;
+}
+
 static inline unsigned long kvm_vcpu_get_hfar(struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.fault.hxfar;
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index 10d77a6..339ec88 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_KVM_ARM_HOST) += hyp/
 obj-y += kvm-arm.o init.o interrupts.o
 obj-y += arm.o handle_exit.o guest.o mmu.o emulate.o reset.o
 obj-y += coproc.o coproc_a15.o coproc_a7.o mmio.o psci.o perf.o
+obj-y += $(KVM)/arm/aarch32.o
 
 obj-y += $(KVM)/arm/vgic/vgic.o
 obj-y += $(KVM)/arm/vgic/vgic-init.o
diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
index eda9ddd..ff9acd1 100644
--- a/arch/arm/kvm/emulate.c
+++ b/arch/arm/kvm/emulate.c
@@ -161,103 +161,6 @@ unsigned long *vcpu_spsr(struct kvm_vcpu *vcpu)
 	}
 }
 
-/*
- * A conditional instruction is allowed to trap, even though it
- * wouldn't be executed.  So let's re-implement the hardware, in
- * software!
- */
-bool kvm_condition_valid(struct kvm_vcpu *vcpu)
-{
-	unsigned long cpsr, cond, insn;
-
-	/*
-	 * Exception Code 0 can only happen if we set HCR.TGE to 1, to
-	 * catch undefined instructions, and then we won't get past
-	 * the arm_exit_handlers test anyway.
-	 */
-	BUG_ON(!kvm_vcpu_trap_get_class(vcpu));
-
-	/* Top two bits non-zero?  Unconditional. */
-	if (kvm_vcpu_get_hsr(vcpu) >> 30)
-		return true;
-
-	cpsr = *vcpu_cpsr(vcpu);
-
-	/* Is condition field valid? */
-	if ((kvm_vcpu_get_hsr(vcpu) & HSR_CV) >> HSR_CV_SHIFT)
-		cond = (kvm_vcpu_get_hsr(vcpu) & HSR_COND) >> HSR_COND_SHIFT;
-	else {
-		/* This can happen in Thumb mode: examine IT state. */
-		unsigned long it;
-
-		it = ((cpsr >> 8) & 0xFC) | ((cpsr >> 25) & 0x3);
-
-		/* it == 0 => unconditional. */
-		if (it == 0)
-			return true;
-
-		/* The cond for this insn works out as the top 4 bits. */
-		cond = (it >> 4);
-	}
-
-	/* Shift makes it look like an ARM-mode instruction */
-	insn = cond << 28;
-	return arm_check_condition(insn, cpsr) != ARM_OPCODE_CONDTEST_FAIL;
-}
-
-/**
- * adjust_itstate - adjust ITSTATE when emulating instructions in IT-block
- * @vcpu:	The VCPU pointer
- *
- * When exceptions occur while instructions are executed in Thumb IF-THEN
- * blocks, the ITSTATE field of the CPSR is not advanced (updated), so we have
- * to do this little bit of work manually. The fields map like this:
- *
- * IT[7:0] -> CPSR[26:25],CPSR[15:10]
- */
-static void kvm_adjust_itstate(struct kvm_vcpu *vcpu)
-{
-	unsigned long itbits, cond;
-	unsigned long cpsr = *vcpu_cpsr(vcpu);
-	bool is_arm = !(cpsr & PSR_T_BIT);
-
-	if (is_arm || !(cpsr & PSR_IT_MASK))
-		return;
-
-	cond = (cpsr & 0xe000) >> 13;
-	itbits = (cpsr & 0x1c00) >> (10 - 2);
-	itbits |= (cpsr & (0x3 << 25)) >> 25;
-
-	/* Perform ITAdvance (see page A-52 in ARM DDI 0406C) */
-	if ((itbits & 0x7) == 0)
-		itbits = cond = 0;
-	else
-		itbits = (itbits << 1) & 0x1f;
-
-	cpsr &= ~PSR_IT_MASK;
-	cpsr |= cond << 13;
-	cpsr |= (itbits & 0x1c) << (10 - 2);
-	cpsr |= (itbits & 0x3) << 25;
-	*vcpu_cpsr(vcpu) = cpsr;
-}
-
-/**
- * kvm_skip_instr - skip a trapped instruction and proceed to the next
- * @vcpu: The vcpu pointer
- */
-void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
-{
-	bool is_thumb;
-
-	is_thumb = !!(*vcpu_cpsr(vcpu) & PSR_T_BIT);
-	if (is_thumb && !is_wide_instr)
-		*vcpu_pc(vcpu) += 2;
-	else
-		*vcpu_pc(vcpu) += 4;
-	kvm_adjust_itstate(vcpu);
-}
-
-
 /******************************************************************************
  * Inject exceptions into the guest
  */
diff --git a/virt/kvm/arm/aarch32.c b/virt/kvm/arm/aarch32.c
index cb02e56..ba4417b 100644
--- a/virt/kvm/arm/aarch32.c
+++ b/virt/kvm/arm/aarch32.c
@@ -24,6 +24,11 @@
 #include <linux/kvm_host.h>
 #include <asm/kvm_emulate.h>
 
+#ifndef CONFIG_ARM64
+#define COMPAT_PSR_T_BIT	PSR_T_BIT
+#define COMPAT_PSR_IT_MASK	PSR_IT_MASK
+#endif
+
 /*
  * stolen from arch/arm/kernel/opcodes.c
  *
-- 
2.9.0

^ permalink raw reply related

* [PULL 11/50] arm64: KVM: Move the AArch32 conditional execution to common code
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

It would make some sense to share the conditional execution code
between 32 and 64bit. In order to achieve this, let's move that
code to virt/kvm/arm/aarch32.c. While we're at it, drop a
superfluous BUG_ON() that wasn't that useful.

Following patches will migrate the 32bit port to that code base.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/kvm/emulate.c                             | 4 +---
 arch/arm64/kvm/Makefile                            | 3 ++-
 arch/arm64/kvm/emulate.c => virt/kvm/arm/aarch32.c | 4 +---
 3 files changed, 4 insertions(+), 7 deletions(-)
 rename arch/arm64/kvm/emulate.c => virt/kvm/arm/aarch32.c (97%)

diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
index af93e3f..eda9ddd 100644
--- a/arch/arm/kvm/emulate.c
+++ b/arch/arm/kvm/emulate.c
@@ -221,9 +221,7 @@ static void kvm_adjust_itstate(struct kvm_vcpu *vcpu)
 	unsigned long cpsr = *vcpu_cpsr(vcpu);
 	bool is_arm = !(cpsr & PSR_T_BIT);
 
-	BUG_ON(is_arm && (cpsr & PSR_IT_MASK));
-
-	if (!(cpsr & PSR_IT_MASK))
+	if (is_arm || !(cpsr & PSR_IT_MASK))
 		return;
 
 	cond = (cpsr & 0xe000) >> 13;
diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
index 695eb3c..d50a82a 100644
--- a/arch/arm64/kvm/Makefile
+++ b/arch/arm64/kvm/Makefile
@@ -16,9 +16,10 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/e
 kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/arm.o $(ARM)/mmu.o $(ARM)/mmio.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/psci.o $(ARM)/perf.o
 
-kvm-$(CONFIG_KVM_ARM_HOST) += emulate.o inject_fault.o regmap.o
+kvm-$(CONFIG_KVM_ARM_HOST) += inject_fault.o regmap.o
 kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o
 kvm-$(CONFIG_KVM_ARM_HOST) += guest.o debug.o reset.o sys_regs.o sys_regs_generic_v8.o
+kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/aarch32.o
 
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-init.o
diff --git a/arch/arm64/kvm/emulate.c b/virt/kvm/arm/aarch32.c
similarity index 97%
rename from arch/arm64/kvm/emulate.c
rename to virt/kvm/arm/aarch32.c
index 40098ad..cb02e56 100644
--- a/arch/arm64/kvm/emulate.c
+++ b/virt/kvm/arm/aarch32.c
@@ -109,9 +109,7 @@ static void kvm_adjust_itstate(struct kvm_vcpu *vcpu)
 	unsigned long cpsr = *vcpu_cpsr(vcpu);
 	bool is_arm = !(cpsr & COMPAT_PSR_T_BIT);
 
-	BUG_ON(is_arm && (cpsr & COMPAT_PSR_IT_MASK));
-
-	if (!(cpsr & COMPAT_PSR_IT_MASK))
+	if (is_arm || !(cpsr & COMPAT_PSR_IT_MASK))
 		return;
 
 	cond = (cpsr & 0xe000) >> 13;
-- 
2.9.0

^ permalink raw reply related

* [PULL 10/50] arm64: KVM: Move kvm_vcpu_get_condition out of emulate.c
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

In order to make emulate.c more generic, move the arch-specific
manupulation bits out of emulate.c.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_emulate.h | 10 ++++++++++
 arch/arm64/kvm/emulate.c             | 11 -----------
 2 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 4cdeae3..b336434d 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -147,6 +147,16 @@ static inline u32 kvm_vcpu_get_hsr(const struct kvm_vcpu *vcpu)
 	return vcpu->arch.fault.esr_el2;
 }
 
+static inline int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu)
+{
+	u32 esr = kvm_vcpu_get_hsr(vcpu);
+
+	if (esr & ESR_ELx_CV)
+		return (esr & ESR_ELx_COND_MASK) >> ESR_ELx_COND_SHIFT;
+
+	return -1;
+}
+
 static inline unsigned long kvm_vcpu_get_hfar(const struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.fault.far_el2;
diff --git a/arch/arm64/kvm/emulate.c b/arch/arm64/kvm/emulate.c
index f87d8fb..40098ad 100644
--- a/arch/arm64/kvm/emulate.c
+++ b/arch/arm64/kvm/emulate.c
@@ -22,7 +22,6 @@
  */
 
 #include <linux/kvm_host.h>
-#include <asm/esr.h>
 #include <asm/kvm_emulate.h>
 
 /*
@@ -52,16 +51,6 @@ static const unsigned short cc_map[16] = {
 	0			/* NV                     */
 };
 
-static int kvm_vcpu_get_condition(const struct kvm_vcpu *vcpu)
-{
-	u32 esr = kvm_vcpu_get_hsr(vcpu);
-
-	if (esr & ESR_ELx_CV)
-		return (esr & ESR_ELx_COND_MASK) >> ESR_ELx_COND_SHIFT;
-
-	return -1;
-}
-
 /*
  * Check if a trapped instruction should have been executed or not.
  */
-- 
2.9.0

^ permalink raw reply related

* [PULL 09/50] arm64: KVM: VHE: reset PSTATE.PAN on entry to EL2
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Vladimir Murzin <vladimir.murzin@arm.com>

SCTLR_EL2.SPAN bit controls what happens with the PSTATE.PAN bit on an
exception. However, this bit has no effect on the PSTATE.PAN when
HCR_EL2.E2H or HCR_EL2.TGE is unset. Thus when VHE is used and
exception taken from a guest PSTATE.PAN bit left unchanged and we
continue with a value guest has set.

To address that always reset PSTATE.PAN on entry from EL1.

Fixes: 1f364c8c48a0 ("arm64: VHE: Add support for running Linux in EL2 mode")

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: <stable@vger.kernel.org> # v4.6+
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/hyp/entry.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index 3967c231..b5926ee 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -96,6 +96,8 @@ ENTRY(__guest_exit)
 
 	add	x1, x1, #VCPU_CONTEXT
 
+	ALTERNATIVE(nop, SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN)
+
 	// Store the guest regs x2 and x3
 	stp	x2, x3,   [x1, #CPU_XREG_OFFSET(2)]
 
-- 
2.9.0

^ permalink raw reply related

* [PULL 08/50] KVM: arm/arm64: Get rid of exported aliases to static functions
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

When rewriting the assembly code to C code, it was useful to have
exported aliases or static functions so that we could keep the existing
common C code unmodified and at the same time rewrite arm64 from
assembly to C code, and later do the arm part.

Now when both are done, we really don't need this level of indirection
anymore, and it's time to save a few lines and brain cells.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/kvm/hyp/switch.c       |  4 +---
 arch/arm/kvm/hyp/tlb.c          | 15 ++++-----------
 arch/arm64/kvm/hyp/debug-sr.c   |  4 +---
 arch/arm64/kvm/hyp/switch.c     |  4 +---
 arch/arm64/kvm/hyp/tlb.c        | 13 +++----------
 arch/arm64/kvm/hyp/vgic-v3-sr.c |  4 +---
 6 files changed, 11 insertions(+), 33 deletions(-)

diff --git a/arch/arm/kvm/hyp/switch.c b/arch/arm/kvm/hyp/switch.c
index b13caa9..37b3365 100644
--- a/arch/arm/kvm/hyp/switch.c
+++ b/arch/arm/kvm/hyp/switch.c
@@ -134,7 +134,7 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
 	return true;
 }
 
-static int __hyp_text __guest_run(struct kvm_vcpu *vcpu)
+int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpu_context *host_ctxt;
 	struct kvm_cpu_context *guest_ctxt;
@@ -191,8 +191,6 @@ again:
 	return exit_code;
 }
 
-__alias(__guest_run) int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
-
 static const char * const __hyp_panic_string[] = {
 	[ARM_EXCEPTION_RESET]      = "\nHYP panic: RST   PC:%08x CPSR:%08x",
 	[ARM_EXCEPTION_UNDEFINED]  = "\nHYP panic: UNDEF PC:%08x CPSR:%08x",
diff --git a/arch/arm/kvm/hyp/tlb.c b/arch/arm/kvm/hyp/tlb.c
index a263600..7296528 100644
--- a/arch/arm/kvm/hyp/tlb.c
+++ b/arch/arm/kvm/hyp/tlb.c
@@ -34,7 +34,7 @@
  * As v7 does not support flushing per IPA, just nuke the whole TLB
  * instead, ignoring the ipa value.
  */
-static void __hyp_text __tlb_flush_vmid(struct kvm *kvm)
+void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm)
 {
 	dsb(ishst);
 
@@ -50,21 +50,14 @@ static void __hyp_text __tlb_flush_vmid(struct kvm *kvm)
 	write_sysreg(0, VTTBR);
 }
 
-__alias(__tlb_flush_vmid) void __kvm_tlb_flush_vmid(struct kvm *kvm);
-
-static void __hyp_text __tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
+void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
 {
-	__tlb_flush_vmid(kvm);
+	__kvm_tlb_flush_vmid(kvm);
 }
 
-__alias(__tlb_flush_vmid_ipa) void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm,
-							    phys_addr_t ipa);
-
-static void __hyp_text __tlb_flush_vm_context(void)
+void __hyp_text __kvm_flush_vm_context(void)
 {
 	write_sysreg(0, TLBIALLNSNHIS);
 	write_sysreg(0, ICIALLUIS);
 	dsb(ish);
 }
-
-__alias(__tlb_flush_vm_context) void __kvm_flush_vm_context(void);
diff --git a/arch/arm64/kvm/hyp/debug-sr.c b/arch/arm64/kvm/hyp/debug-sr.c
index 33342a7..4ba5c90 100644
--- a/arch/arm64/kvm/hyp/debug-sr.c
+++ b/arch/arm64/kvm/hyp/debug-sr.c
@@ -131,9 +131,7 @@ void __hyp_text __debug_cond_restore_host_state(struct kvm_vcpu *vcpu)
 		vcpu->arch.debug_flags &= ~KVM_ARM64_DEBUG_DIRTY;
 }
 
-static u32 __hyp_text __debug_read_mdcr_el2(void)
+u32 __hyp_text __kvm_get_mdcr_el2(void)
 {
 	return read_sysreg(mdcr_el2);
 }
-
-__alias(__debug_read_mdcr_el2) u32 __kvm_get_mdcr_el2(void);
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 5a84b45..35d2e09 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -232,7 +232,7 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
 	return true;
 }
 
-static int __hyp_text __guest_run(struct kvm_vcpu *vcpu)
+int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpu_context *host_ctxt;
 	struct kvm_cpu_context *guest_ctxt;
@@ -293,8 +293,6 @@ again:
 	return exit_code;
 }
 
-__alias(__guest_run) int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
-
 static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n";
 
 static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par)
diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/tlb.c
index be8177c..9cc0ea7 100644
--- a/arch/arm64/kvm/hyp/tlb.c
+++ b/arch/arm64/kvm/hyp/tlb.c
@@ -17,7 +17,7 @@
 
 #include <asm/kvm_hyp.h>
 
-static void __hyp_text __tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
+void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
 {
 	dsb(ishst);
 
@@ -48,10 +48,7 @@ static void __hyp_text __tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
 	write_sysreg(0, vttbr_el2);
 }
 
-__alias(__tlb_flush_vmid_ipa) void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm,
-							    phys_addr_t ipa);
-
-static void __hyp_text __tlb_flush_vmid(struct kvm *kvm)
+void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm)
 {
 	dsb(ishst);
 
@@ -67,14 +64,10 @@ static void __hyp_text __tlb_flush_vmid(struct kvm *kvm)
 	write_sysreg(0, vttbr_el2);
 }
 
-__alias(__tlb_flush_vmid) void __kvm_tlb_flush_vmid(struct kvm *kvm);
-
-static void __hyp_text __tlb_flush_vm_context(void)
+void __hyp_text __kvm_flush_vm_context(void)
 {
 	dsb(ishst);
 	asm volatile("tlbi alle1is	\n"
 		     "ic ialluis	  ": : );
 	dsb(ish);
 }
-
-__alias(__tlb_flush_vm_context) void __kvm_flush_vm_context(void);
diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c
index 5f8f80b..ee1ea63 100644
--- a/arch/arm64/kvm/hyp/vgic-v3-sr.c
+++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c
@@ -335,9 +335,7 @@ void __hyp_text __vgic_v3_init_lrs(void)
 		__gic_v3_set_lr(0, i);
 }
 
-static u64 __hyp_text __vgic_v3_read_ich_vtr_el2(void)
+u64 __hyp_text __vgic_v3_get_ich_vtr_el2(void)
 {
 	return read_gicreg(ICH_VTR_EL2);
 }
-
-__alias(__vgic_v3_read_ich_vtr_el2) u64 __vgic_v3_get_ich_vtr_el2(void);
-- 
2.9.0

^ permalink raw reply related

* [PULL 07/50] arm64/kvm: remove unused stub functions
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Mark Rutland <mark.rutland@arm.com>

Now that 32-bit KVM no longer performs cache maintenance for page table
updates, we no longer need empty stubs for arm64. Remove them.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: kvmarm at lists.cs.columbia.edu
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/include/asm/kvm_mmu.h | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index b6bb834..8f99ab6 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -166,12 +166,6 @@ void kvm_clear_hyp_idmap(void);
 #define	kvm_set_pte(ptep, pte)		set_pte(ptep, pte)
 #define	kvm_set_pmd(pmdp, pmd)		set_pmd(pmdp, pmd)
 
-static inline void kvm_clean_pgd(pgd_t *pgd) {}
-static inline void kvm_clean_pmd(pmd_t *pmd) {}
-static inline void kvm_clean_pmd_entry(pmd_t *pmd) {}
-static inline void kvm_clean_pte(pte_t *pte) {}
-static inline void kvm_clean_pte_entry(pte_t *pte) {}
-
 static inline pte_t kvm_s2pte_mkwrite(pte_t pte)
 {
 	pte_val(pte) |= PTE_S2_RDWR;
-- 
2.9.0

^ permalink raw reply related

* [PULL 06/50] arm/kvm: excise redundant cache maintenance
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Mark Rutland <mark.rutland@arm.com>

When modifying Stage-2 page tables, we perform cache maintenance to
account for non-coherent page table walks. However, this is unnecessary,
as page table walks are guaranteed to be coherent in the presence of the
virtualization extensions.

Per ARM DDI 0406C.c, section B1.7 ("The Virtualization Extensions"), the
virtualization extensions mandate the multiprocessing extensions.

Per ARM DDI 0406C.c, section B3.10.1 ("General TLB maintenance
requirements"), as described in the sub-section titled "TLB maintenance
operations and the memory order model", this maintenance is not required
in the presence of the multiprocessing extensions.

Hence, we need not perform this cache maintenance when modifying Stage-2
entries.

This patch removes the logic for performing the redundant maintenance.
To ensure visibility and ordering of updates, a dsb(ishst) that was
otherwise implicit in the maintenance is folded into kvm_set_pmd() and
kvm_set_pte().

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: kvmarm at lists.cs.columbia.edu
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/include/asm/kvm_mmu.h | 28 ++--------------------------
 arch/arm/kvm/mmu.c             |  2 --
 2 files changed, 2 insertions(+), 28 deletions(-)

diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index 3bb803d..74a44727 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -63,37 +63,13 @@ void kvm_clear_hyp_idmap(void);
 static inline void kvm_set_pmd(pmd_t *pmd, pmd_t new_pmd)
 {
 	*pmd = new_pmd;
-	flush_pmd_entry(pmd);
+	dsb(ishst);
 }
 
 static inline void kvm_set_pte(pte_t *pte, pte_t new_pte)
 {
 	*pte = new_pte;
-	/*
-	 * flush_pmd_entry just takes a void pointer and cleans the necessary
-	 * cache entries, so we can reuse the function for ptes.
-	 */
-	flush_pmd_entry(pte);
-}
-
-static inline void kvm_clean_pgd(pgd_t *pgd)
-{
-	clean_dcache_area(pgd, PTRS_PER_S2_PGD * sizeof(pgd_t));
-}
-
-static inline void kvm_clean_pmd(pmd_t *pmd)
-{
-	clean_dcache_area(pmd, PTRS_PER_PMD * sizeof(pmd_t));
-}
-
-static inline void kvm_clean_pmd_entry(pmd_t *pmd)
-{
-	clean_pmd_entry(pmd);
-}
-
-static inline void kvm_clean_pte(pte_t *pte)
-{
-	clean_pte_table(pte);
+	dsb(ishst);
 }
 
 static inline pte_t kvm_s2pte_mkwrite(pte_t pte)
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 29d0b23..344755d 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -744,7 +744,6 @@ int kvm_alloc_stage2_pgd(struct kvm *kvm)
 	if (!pgd)
 		return -ENOMEM;
 
-	kvm_clean_pgd(pgd);
 	kvm->arch.pgd = pgd;
 	return 0;
 }
@@ -936,7 +935,6 @@ static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
 		if (!cache)
 			return 0; /* ignore calls from kvm_set_spte_hva */
 		pte = mmu_memory_cache_alloc(cache);
-		kvm_clean_pte(pte);
 		pmd_populate_kernel(NULL, pmd, pte);
 		get_page(virt_to_page(pmd));
 	}
-- 
2.9.0

^ permalink raw reply related

* [PULL 05/50] KVM: arm: vgic: Drop build compatibility hack for older kernel versions
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Marc Zyngier <marc.zyngier@arm.com>

As kvm_set_routing_entry() was changing prototype between 4.7 and 4.8,
an ugly hack was put in place in order to survive both building in
-next and the merge window.

Now that everything has been merged, let's dump the compatibility
hack for good.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-irqfd.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-irqfd.c b/virt/kvm/arm/vgic/vgic-irqfd.c
index b31a51a..d918dcf 100644
--- a/virt/kvm/arm/vgic/vgic-irqfd.c
+++ b/virt/kvm/arm/vgic/vgic-irqfd.c
@@ -46,15 +46,9 @@ static int vgic_irqfd_set_irq(struct kvm_kernel_irq_routing_entry *e,
  * @ue: user api routing entry handle
  * return 0 on success, -EINVAL on errors.
  */
-#ifdef KVM_CAP_X2APIC_API
 int kvm_set_routing_entry(struct kvm *kvm,
 			  struct kvm_kernel_irq_routing_entry *e,
 			  const struct kvm_irq_routing_entry *ue)
-#else
-/* Remove this version and the ifdefery once merged into 4.8 */
-int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e,
-			  const struct kvm_irq_routing_entry *ue)
-#endif
 {
 	int r = -EINVAL;
 
-- 
2.9.0

^ permalink raw reply related

* [PULL 04/50] arm64: KVM: Optimize __guest_enter/exit() to save a few instructions
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

From: Shanker Donthineni <shankerd@codeaurora.org>

We are doing an unnecessary stack push/pop operation when restoring
the guest registers x0-x18 in __guest_enter(). This patch saves the
two instructions by using x18 as a base register. No need to store
the vcpu context pointer in stack because it is redundant, the same
information is available in tpidr_el2. The function __guest_exit()
calling convention is slightly modified, caller only pushes the regs
x0-x1 to stack instead of regs x0-x3.

Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm64/kvm/hyp/entry.S     | 101 ++++++++++++++++++++---------------------
 arch/arm64/kvm/hyp/hyp-entry.S |  37 ++++++---------
 2 files changed, 63 insertions(+), 75 deletions(-)

diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index ce9e5e5..3967c231 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -55,79 +55,78 @@
  */
 ENTRY(__guest_enter)
 	// x0: vcpu
-	// x1: host/guest context
-	// x2-x18: clobbered by macros
+	// x1: host context
+	// x2-x17: clobbered by macros
+	// x18: guest context
 
 	// Store the host regs
 	save_callee_saved_regs x1
 
-	// Preserve vcpu & host_ctxt for use at exit time
-	stp	x0, x1, [sp, #-16]!
+	// Store the host_ctxt for use at exit time
+	str	x1, [sp, #-16]!
 
-	add	x1, x0, #VCPU_CONTEXT
+	add	x18, x0, #VCPU_CONTEXT
 
-	// Prepare x0-x1 for later restore by pushing them onto the stack
-	ldp	x2, x3, [x1, #CPU_XREG_OFFSET(0)]
-	stp	x2, x3, [sp, #-16]!
+	// Restore guest regs x0-x17
+	ldp	x0, x1,   [x18, #CPU_XREG_OFFSET(0)]
+	ldp	x2, x3,   [x18, #CPU_XREG_OFFSET(2)]
+	ldp	x4, x5,   [x18, #CPU_XREG_OFFSET(4)]
+	ldp	x6, x7,   [x18, #CPU_XREG_OFFSET(6)]
+	ldp	x8, x9,   [x18, #CPU_XREG_OFFSET(8)]
+	ldp	x10, x11, [x18, #CPU_XREG_OFFSET(10)]
+	ldp	x12, x13, [x18, #CPU_XREG_OFFSET(12)]
+	ldp	x14, x15, [x18, #CPU_XREG_OFFSET(14)]
+	ldp	x16, x17, [x18, #CPU_XREG_OFFSET(16)]
 
-	// x2-x18
-	ldp	x2, x3,   [x1, #CPU_XREG_OFFSET(2)]
-	ldp	x4, x5,   [x1, #CPU_XREG_OFFSET(4)]
-	ldp	x6, x7,   [x1, #CPU_XREG_OFFSET(6)]
-	ldp	x8, x9,   [x1, #CPU_XREG_OFFSET(8)]
-	ldp	x10, x11, [x1, #CPU_XREG_OFFSET(10)]
-	ldp	x12, x13, [x1, #CPU_XREG_OFFSET(12)]
-	ldp	x14, x15, [x1, #CPU_XREG_OFFSET(14)]
-	ldp	x16, x17, [x1, #CPU_XREG_OFFSET(16)]
-	ldr	x18,      [x1, #CPU_XREG_OFFSET(18)]
-
-	// x19-x29, lr
-	restore_callee_saved_regs x1
-
-	// Last bits of the 64bit state
-	ldp	x0, x1, [sp], #16
+	// Restore guest regs x19-x29, lr
+	restore_callee_saved_regs x18
+
+	// Restore guest reg x18
+	ldr	x18,      [x18, #CPU_XREG_OFFSET(18)]
 
 	// Do not touch any register after this!
 	eret
 ENDPROC(__guest_enter)
 
 ENTRY(__guest_exit)
-	// x0: vcpu
-	// x1: return code
-	// x2-x3: free
-	// x4-x29,lr: vcpu regs
-	// vcpu x0-x3 on the stack
-
-	add	x2, x0, #VCPU_CONTEXT
-
-	stp	x4, x5,   [x2, #CPU_XREG_OFFSET(4)]
-	stp	x6, x7,   [x2, #CPU_XREG_OFFSET(6)]
-	stp	x8, x9,   [x2, #CPU_XREG_OFFSET(8)]
-	stp	x10, x11, [x2, #CPU_XREG_OFFSET(10)]
-	stp	x12, x13, [x2, #CPU_XREG_OFFSET(12)]
-	stp	x14, x15, [x2, #CPU_XREG_OFFSET(14)]
-	stp	x16, x17, [x2, #CPU_XREG_OFFSET(16)]
-	str	x18,      [x2, #CPU_XREG_OFFSET(18)]
-
-	ldp	x6, x7, [sp], #16	// x2, x3
-	ldp	x4, x5, [sp], #16	// x0, x1
-
-	stp	x4, x5, [x2, #CPU_XREG_OFFSET(0)]
-	stp	x6, x7, [x2, #CPU_XREG_OFFSET(2)]
+	// x0: return code
+	// x1: vcpu
+	// x2-x29,lr: vcpu regs
+	// vcpu x0-x1 on the stack
+
+	add	x1, x1, #VCPU_CONTEXT
+
+	// Store the guest regs x2 and x3
+	stp	x2, x3,   [x1, #CPU_XREG_OFFSET(2)]
+
+	// Retrieve the guest regs x0-x1 from the stack
+	ldp	x2, x3, [sp], #16	// x0, x1
+
+	// Store the guest regs x0-x1 and x4-x18
+	stp	x2, x3,   [x1, #CPU_XREG_OFFSET(0)]
+	stp	x4, x5,   [x1, #CPU_XREG_OFFSET(4)]
+	stp	x6, x7,   [x1, #CPU_XREG_OFFSET(6)]
+	stp	x8, x9,   [x1, #CPU_XREG_OFFSET(8)]
+	stp	x10, x11, [x1, #CPU_XREG_OFFSET(10)]
+	stp	x12, x13, [x1, #CPU_XREG_OFFSET(12)]
+	stp	x14, x15, [x1, #CPU_XREG_OFFSET(14)]
+	stp	x16, x17, [x1, #CPU_XREG_OFFSET(16)]
+	str	x18,      [x1, #CPU_XREG_OFFSET(18)]
+
+	// Store the guest regs x19-x29, lr
+	save_callee_saved_regs x1
 
-	save_callee_saved_regs x2
+	// Restore the host_ctxt from the stack
+	ldr	x2, [sp], #16
 
-	// Restore vcpu & host_ctxt from the stack
-	// (preserving return code in x1)
-	ldp	x0, x2, [sp], #16
 	// Now restore the host regs
 	restore_callee_saved_regs x2
 
-	mov	x0, x1
 	ret
 ENDPROC(__guest_exit)
 
 ENTRY(__fpsimd_guest_restore)
+	stp	x2, x3, [sp, #-16]!
 	stp	x4, lr, [sp, #-16]!
 
 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index f6d9694..d6cae54 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -27,16 +27,6 @@
 	.text
 	.pushsection	.hyp.text, "ax"
 
-.macro	save_x0_to_x3
-	stp	x0, x1, [sp, #-16]!
-	stp	x2, x3, [sp, #-16]!
-.endm
-
-.macro	restore_x0_to_x3
-	ldp	x2, x3, [sp], #16
-	ldp	x0, x1, [sp], #16
-.endm
-
 .macro do_el2_call
 	/*
 	 * Shuffle the parameters before calling the function
@@ -79,23 +69,23 @@ ENTRY(__kvm_hyp_teardown)
 ENDPROC(__kvm_hyp_teardown)
 	
 el1_sync:				// Guest trapped into EL2
-	save_x0_to_x3
+	stp	x0, x1, [sp, #-16]!
 
 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
 	mrs	x1, esr_el2
 alternative_else
 	mrs	x1, esr_el1
 alternative_endif
-	lsr	x2, x1, #ESR_ELx_EC_SHIFT
+	lsr	x0, x1, #ESR_ELx_EC_SHIFT
 
-	cmp	x2, #ESR_ELx_EC_HVC64
+	cmp	x0, #ESR_ELx_EC_HVC64
 	b.ne	el1_trap
 
-	mrs	x3, vttbr_el2		// If vttbr is valid, the 64bit guest
-	cbnz	x3, el1_trap		// called HVC
+	mrs	x1, vttbr_el2		// If vttbr is valid, the 64bit guest
+	cbnz	x1, el1_trap		// called HVC
 
 	/* Here, we're pretty sure the host called HVC. */
-	restore_x0_to_x3
+	ldp	x0, x1, [sp], #16
 
 	cmp	x0, #HVC_GET_VECTORS
 	b.ne	1f
@@ -113,22 +103,21 @@ alternative_endif
 
 el1_trap:
 	/*
-	 * x1: ESR
-	 * x2: ESR_EC
+	 * x0: ESR_EC
 	 */
 
 	/* Guest accessed VFP/SIMD registers, save host, restore Guest */
-	cmp	x2, #ESR_ELx_EC_FP_ASIMD
+	cmp	x0, #ESR_ELx_EC_FP_ASIMD
 	b.eq	__fpsimd_guest_restore
 
-	mrs	x0, tpidr_el2
-	mov	x1, #ARM_EXCEPTION_TRAP
+	mrs	x1, tpidr_el2
+	mov	x0, #ARM_EXCEPTION_TRAP
 	b	__guest_exit
 
 el1_irq:
-	save_x0_to_x3
-	mrs	x0, tpidr_el2
-	mov	x1, #ARM_EXCEPTION_IRQ
+	stp     x0, x1, [sp, #-16]!
+	mrs	x1, tpidr_el2
+	mov	x0, #ARM_EXCEPTION_IRQ
 	b	__guest_exit
 
 ENTRY(__hyp_do_panic)
-- 
2.9.0

^ permalink raw reply related

* [PULL 03/50] KVM: arm/arm64: Rename vgic_attr_regs_access to vgic_attr_regs_access_v2
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

Just a rename so we can implement a v3-specific function later.

We take the chance to get rid of the V2/V3 ops comments as well.

No functional change.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-kvm-device.c | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 19fa331..163b057 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -294,17 +294,17 @@ static bool lock_all_vcpus(struct kvm *kvm)
 	return true;
 }
 
-/** vgic_attr_regs_access: allows user space to read/write VGIC registers
- *
- * @dev: kvm device handle
- * @attr: kvm device attribute
- * @reg: address the value is read or written
- * @is_write: write flag
+/**
+ * vgic_attr_regs_access_v2 - allows user space to access VGIC v2 state
  *
+ * @dev:      kvm device handle
+ * @attr:     kvm device attribute
+ * @reg:      address the value is read or written
+ * @is_write: true if userspace is writing a register
  */
-static int vgic_attr_regs_access(struct kvm_device *dev,
-				 struct kvm_device_attr *attr,
-				 u32 *reg, bool is_write)
+static int vgic_attr_regs_access_v2(struct kvm_device *dev,
+				    struct kvm_device_attr *attr,
+				    u32 *reg, bool is_write)
 {
 	struct vgic_reg_attr reg_attr;
 	gpa_t addr;
@@ -347,8 +347,6 @@ out:
 	return ret;
 }
 
-/* V2 ops */
-
 static int vgic_v2_set_attr(struct kvm_device *dev,
 			    struct kvm_device_attr *attr)
 {
@@ -367,7 +365,7 @@ static int vgic_v2_set_attr(struct kvm_device *dev,
 		if (get_user(reg, uaddr))
 			return -EFAULT;
 
-		return vgic_attr_regs_access(dev, attr, &reg, true);
+		return vgic_attr_regs_access_v2(dev, attr, &reg, true);
 	}
 	}
 
@@ -389,7 +387,7 @@ static int vgic_v2_get_attr(struct kvm_device *dev,
 		u32 __user *uaddr = (u32 __user *)(long)attr->addr;
 		u32 reg = 0;
 
-		ret = vgic_attr_regs_access(dev, attr, &reg, false);
+		ret = vgic_attr_regs_access_v2(dev, attr, &reg, false);
 		if (ret)
 			return ret;
 		return put_user(reg, uaddr);
@@ -433,8 +431,6 @@ struct kvm_device_ops kvm_arm_vgic_v2_ops = {
 	.has_attr = vgic_v2_has_attr,
 };
 
-/* V3 ops */
-
 #ifdef CONFIG_KVM_ARM_VGIC_V3
 
 static int vgic_v3_set_attr(struct kvm_device *dev,
-- 
2.9.0

^ permalink raw reply related

* [PULL 02/50] KVM: arm/arm64: Factor out vgic_attr_regs_access functionality
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

As we are about to deal with multiple data types and situations where
the vgic should not be initialized when doing userspace accesses on the
register attributes, factor out the functionality of
vgic_attr_regs_access into smaller bits which can be reused by a new
function later.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-kvm-device.c | 100 ++++++++++++++++++++++++++----------
 1 file changed, 73 insertions(+), 27 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 1813f93..19fa331 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -233,6 +233,67 @@ int kvm_register_vgic_device(unsigned long type)
 	return ret;
 }
 
+struct vgic_reg_attr {
+	struct kvm_vcpu *vcpu;
+	gpa_t addr;
+};
+
+static int parse_vgic_v2_attr(struct kvm_device *dev,
+			      struct kvm_device_attr *attr,
+			      struct vgic_reg_attr *reg_attr)
+{
+	int cpuid;
+
+	cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >>
+		 KVM_DEV_ARM_VGIC_CPUID_SHIFT;
+
+	if (cpuid >= atomic_read(&dev->kvm->online_vcpus))
+		return -EINVAL;
+
+	reg_attr->vcpu = kvm_get_vcpu(dev->kvm, cpuid);
+	reg_attr->addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
+
+	return 0;
+}
+
+/* unlocks vcpus from @vcpu_lock_idx and smaller */
+static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
+{
+	struct kvm_vcpu *tmp_vcpu;
+
+	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
+		tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
+		mutex_unlock(&tmp_vcpu->mutex);
+	}
+}
+
+static void unlock_all_vcpus(struct kvm *kvm)
+{
+	unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
+}
+
+/* Returns true if all vcpus were locked, false otherwise */
+static bool lock_all_vcpus(struct kvm *kvm)
+{
+	struct kvm_vcpu *tmp_vcpu;
+	int c;
+
+	/*
+	 * Any time a vcpu is run, vcpu_load is called which tries to grab the
+	 * vcpu->mutex.  By grabbing the vcpu->mutex of all VCPUs we ensure
+	 * that no other VCPUs are run and fiddle with the vgic state while we
+	 * access it.
+	 */
+	kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
+		if (!mutex_trylock(&tmp_vcpu->mutex)) {
+			unlock_vcpus(kvm, c - 1);
+			return false;
+		}
+	}
+
+	return true;
+}
+
 /** vgic_attr_regs_access: allows user space to read/write VGIC registers
  *
  * @dev: kvm device handle
@@ -245,15 +306,17 @@ static int vgic_attr_regs_access(struct kvm_device *dev,
 				 struct kvm_device_attr *attr,
 				 u32 *reg, bool is_write)
 {
+	struct vgic_reg_attr reg_attr;
 	gpa_t addr;
-	int cpuid, ret, c;
-	struct kvm_vcpu *vcpu, *tmp_vcpu;
-	int vcpu_lock_idx = -1;
+	struct kvm_vcpu *vcpu;
+	int ret;
 
-	cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >>
-		 KVM_DEV_ARM_VGIC_CPUID_SHIFT;
-	vcpu = kvm_get_vcpu(dev->kvm, cpuid);
-	addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
+	ret = parse_vgic_v2_attr(dev, attr, &reg_attr);
+	if (ret)
+		return ret;
+
+	vcpu = reg_attr.vcpu;
+	addr = reg_attr.addr;
 
 	mutex_lock(&dev->kvm->lock);
 
@@ -261,24 +324,11 @@ static int vgic_attr_regs_access(struct kvm_device *dev,
 	if (ret)
 		goto out;
 
-	if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) {
-		ret = -EINVAL;
+	if (!lock_all_vcpus(dev->kvm)) {
+		ret = -EBUSY;
 		goto out;
 	}
 
-	/*
-	 * Any time a vcpu is run, vcpu_load is called which tries to grab the
-	 * vcpu->mutex.  By grabbing the vcpu->mutex of all VCPUs we ensure
-	 * that no other VCPUs are run and fiddle with the vgic state while we
-	 * access it.
-	 */
-	ret = -EBUSY;
-	kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) {
-		if (!mutex_trylock(&tmp_vcpu->mutex))
-			goto out;
-		vcpu_lock_idx = c;
-	}
-
 	switch (attr->group) {
 	case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
 		ret = vgic_v2_cpuif_uaccess(vcpu, is_write, addr, reg);
@@ -291,12 +341,8 @@ static int vgic_attr_regs_access(struct kvm_device *dev,
 		break;
 	}
 
+	unlock_all_vcpus(dev->kvm);
 out:
-	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
-		tmp_vcpu = kvm_get_vcpu(dev->kvm, vcpu_lock_idx);
-		mutex_unlock(&tmp_vcpu->mutex);
-	}
-
 	mutex_unlock(&dev->kvm->lock);
 	return ret;
 }
-- 
2.9.0

^ permalink raw reply related

* [PULL 01/50] KVM: arm/arm64: Add VGICv3 save/restore API documentation
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20160927180558.14699-1-christoffer.dall@linaro.org>

Factor out the GICv3 and ITS-specific documentation into a separate
documentation file.  Add description for how to access distributor,
redistributor, and CPU interface registers for GICv3 in this new file,
and add a group for accessing level triggered IRQ information for GICv3
as well.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 Documentation/virtual/kvm/devices/arm-vgic-its.txt |  38 ++++
 Documentation/virtual/kvm/devices/arm-vgic-v3.txt  | 206 +++++++++++++++++++++
 Documentation/virtual/kvm/devices/arm-vgic.txt     |  52 ++----
 3 files changed, 261 insertions(+), 35 deletions(-)
 create mode 100644 Documentation/virtual/kvm/devices/arm-vgic-its.txt
 create mode 100644 Documentation/virtual/kvm/devices/arm-vgic-v3.txt

diff --git a/Documentation/virtual/kvm/devices/arm-vgic-its.txt b/Documentation/virtual/kvm/devices/arm-vgic-its.txt
new file mode 100644
index 0000000..6081a5b
--- /dev/null
+++ b/Documentation/virtual/kvm/devices/arm-vgic-its.txt
@@ -0,0 +1,38 @@
+ARM Virtual Interrupt Translation Service (ITS)
+===============================================
+
+Device types supported:
+  KVM_DEV_TYPE_ARM_VGIC_ITS    ARM Interrupt Translation Service Controller
+
+The ITS allows MSI(-X) interrupts to be injected into guests. This extension is
+optional.  Creating a virtual ITS controller also requires a host GICv3 (see
+arm-vgic-v3.txt), but does not depend on having physical ITS controllers.
+
+There can be multiple ITS controllers per guest, each of them has to have
+a separate, non-overlapping MMIO region.
+
+
+Groups:
+  KVM_DEV_ARM_VGIC_GRP_ADDR
+  Attributes:
+    KVM_VGIC_ITS_ADDR_TYPE (rw, 64-bit)
+      Base address in the guest physical address space of the GICv3 ITS
+      control register frame.
+      This address needs to be 64K aligned and the region covers 128K.
+  Errors:
+    -E2BIG:  Address outside of addressable IPA range
+    -EINVAL: Incorrectly aligned address
+    -EEXIST: Address already configured
+    -EFAULT: Invalid user pointer for attr->addr.
+    -ENODEV: Incorrect attribute or the ITS is not supported.
+
+
+  KVM_DEV_ARM_VGIC_GRP_CTRL
+  Attributes:
+    KVM_DEV_ARM_VGIC_CTRL_INIT
+      request the initialization of the ITS, no additional parameter in
+      kvm_device_attr.addr.
+  Errors:
+    -ENXIO:  ITS not properly configured as required prior to setting
+             this attribute
+    -ENOMEM: Memory shortage when allocating ITS internal data
diff --git a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
new file mode 100644
index 0000000..9348b3c
--- /dev/null
+++ b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
@@ -0,0 +1,206 @@
+ARM Virtual Generic Interrupt Controller v3 and later (VGICv3)
+==============================================================
+
+
+Device types supported:
+  KVM_DEV_TYPE_ARM_VGIC_V3     ARM Generic Interrupt Controller v3.0
+
+Only one VGIC instance may be instantiated through this API.  The created VGIC
+will act as the VM interrupt controller, requiring emulated user-space devices
+to inject interrupts to the VGIC instead of directly to CPUs.  It is not
+possible to create both a GICv3 and GICv2 on the same VM.
+
+Creating a guest GICv3 device requires a host GICv3 as well.
+
+
+Groups:
+  KVM_DEV_ARM_VGIC_GRP_ADDR
+  Attributes:
+    KVM_VGIC_V3_ADDR_TYPE_DIST (rw, 64-bit)
+      Base address in the guest physical address space of the GICv3 distributor
+      register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+      This address needs to be 64K aligned and the region covers 64 KByte.
+
+    KVM_VGIC_V3_ADDR_TYPE_REDIST (rw, 64-bit)
+      Base address in the guest physical address space of the GICv3
+      redistributor register mappings. There are two 64K pages for each
+      VCPU and all of the redistributor pages are contiguous.
+      Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+      This address needs to be 64K aligned.
+  Errors:
+    -E2BIG:  Address outside of addressable IPA range
+    -EINVAL: Incorrectly aligned address
+    -EEXIST: Address already configured
+    -ENXIO:  The group or attribute is unknown/unsupported for this device
+             or hardware support is missing.
+    -EFAULT: Invalid user pointer for attr->addr.
+
+
+
+  KVM_DEV_ARM_VGIC_GRP_DIST_REGS
+  KVM_DEV_ARM_VGIC_GRP_REDIST_REGS
+  Attributes:
+    The attr field of kvm_device_attr encodes two values:
+    bits:     | 63   ....  32  |  31   ....    0 |
+    values:   |      mpidr     |      offset     |
+
+    All distributor regs are (rw, 32-bit) and kvm_device_attr.addr points to a
+    __u32 value.  64-bit registers must be accessed by separately accessing the
+    lower and higher word.
+
+    Writes to read-only registers are ignored by the kernel.
+
+    KVM_DEV_ARM_VGIC_GRP_DIST_REGS accesses the main distributor registers.
+    KVM_DEV_ARM_VGIC_GRP_REDIST_REGS accesses the redistributor of the CPU
+    specified by the mpidr.
+
+    The offset is relative to the "[Re]Distributor base address" as defined
+    in the GICv3/4 specs.  Getting or setting such a register has the same
+    effect as reading or writing the register on real hardware, except for the
+    following registers: GICD_STATUSR, GICR_STATUSR, GICD_ISPENDR,
+    GICR_ISPENDR0, GICD_ICPENDR, and GICR_ICPENDR0.  These registers behave
+    differently when accessed via this interface compared to their
+    architecturally defined behavior to allow software a full view of the
+    VGIC's internal state.
+
+    The mpidr field is used to specify which
+    redistributor is accessed.  The mpidr is ignored for the distributor.
+
+    The mpidr encoding is based on the affinity information in the
+    architecture defined MPIDR, and the field is encoded as follows:
+      | 63 .... 56 | 55 .... 48 | 47 .... 40 | 39 .... 32 |
+      |    Aff3    |    Aff2    |    Aff1    |    Aff0    |
+
+    Note that distributor fields are not banked, but return the same value
+    regardless of the mpidr used to access the register.
+
+    The GICD_STATUSR and GICR_STATUSR registers are architecturally defined such
+    that a write of a clear bit has no effect, whereas a write with a set bit
+    clears that value.  To allow userspace to freely set the values of these two
+    registers, setting the attributes with the register offsets for these two
+    registers simply sets the non-reserved bits to the value written.
+
+
+    Accesses (reads and writes) to the GICD_ISPENDR register region and
+    GICR_ISPENDR0 registers get/set the value of the latched pending state for
+    the interrupts.
+
+    This is identical to the value returned by a guest read from ISPENDR for an
+    edge triggered interrupt, but may differ for level triggered interrupts.
+    For edge triggered interrupts, once an interrupt becomes pending (whether
+    because of an edge detected on the input line or because of a guest write
+    to ISPENDR) this state is "latched", and only cleared when either the
+    interrupt is activated or when the guest writes to ICPENDR. A level
+    triggered interrupt may be pending either because the level input is held
+    high by a device, or because of a guest write to the ISPENDR register. Only
+    ISPENDR writes are latched; if the device lowers the line level then the
+    interrupt is no longer pending unless the guest also wrote to ISPENDR, and
+    conversely writes to ICPENDR or activations of the interrupt do not clear
+    the pending status if the line level is still being held high.  (These
+    rules are documented in the GICv3 specification descriptions of the ICPENDR
+    and ISPENDR registers.) For a level triggered interrupt the value accessed
+    here is that of the latch which is set by ISPENDR and cleared by ICPENDR or
+    interrupt activation, whereas the value returned by a guest read from
+    ISPENDR is the logical OR of the latch value and the input line level.
+
+    Raw access to the latch state is provided to userspace so that it can save
+    and restore the entire GIC internal state (which is defined by the
+    combination of the current input line level and the latch state, and cannot
+    be deduced from purely the line level and the value of the ISPENDR
+    registers).
+
+    Accesses to GICD_ICPENDR register region and GICR_ICPENDR0 registers have
+    RAZ/WI semantics, meaning that reads always return 0 and writes are always
+    ignored.
+
+  Errors:
+    -ENXIO: Getting or setting this register is not yet supported
+    -EBUSY: One or more VCPUs are running
+
+
+  KVM_DEV_ARM_VGIC_CPU_SYSREGS
+  Attributes:
+    The attr field of kvm_device_attr encodes two values:
+    bits:     | 63      ....       32 | 31  ....  16 | 15  ....  0 |
+    values:   |         mpidr         |      RES     |    instr    |
+
+    The mpidr field encodes the CPU ID based on the affinity information in the
+    architecture defined MPIDR, and the field is encoded as follows:
+      | 63 .... 56 | 55 .... 48 | 47 .... 40 | 39 .... 32 |
+      |    Aff3    |    Aff2    |    Aff1    |    Aff0    |
+
+    The instr field encodes the system register to access based on the fields
+    defined in the A64 instruction set encoding for system register access
+    (RES means the bits are reserved for future use and should be zero):
+
+      | 15 ... 14 | 13 ... 11 | 10 ... 7 | 6 ... 3 | 2 ... 0 |
+      |   Op 0    |    Op1    |    CRn   |   CRm   |   Op2   |
+
+    All system regs accessed through this API are (rw, 64-bit) and
+    kvm_device_attr.addr points to a __u64 value.
+
+    KVM_DEV_ARM_VGIC_CPU_SYSREGS accesses the CPU interface registers for the
+    CPU specified by the mpidr field.
+
+  Errors:
+    -ENXIO: Getting or setting this register is not yet supported
+    -EBUSY: VCPU is running
+    -EINVAL: Invalid mpidr supplied
+
+
+  KVM_DEV_ARM_VGIC_GRP_NR_IRQS
+  Attributes:
+    A value describing the number of interrupts (SGI, PPI and SPI) for
+    this GIC instance, ranging from 64 to 1024, in increments of 32.
+
+    kvm_device_attr.addr points to a __u32 value.
+
+  Errors:
+    -EINVAL: Value set is out of the expected range
+    -EBUSY: Value has already be set.
+
+
+  KVM_DEV_ARM_VGIC_GRP_CTRL
+  Attributes:
+    KVM_DEV_ARM_VGIC_CTRL_INIT
+      request the initialization of the VGIC, no additional parameter in
+      kvm_device_attr.addr.
+  Errors:
+    -ENXIO: VGIC not properly configured as required prior to calling
+     this attribute
+    -ENODEV: no online VCPU
+    -ENOMEM: memory shortage when allocating vgic internal data
+
+
+  KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO
+  Attributes:
+    The attr field of kvm_device_attr encodes the following values:
+    bits:     | 63      ....       32 | 31   ....    10 | 9  ....  0 |
+    values:   |         mpidr         |      info       |   vINTID   |
+
+    The vINTID specifies which set of IRQs is reported on.
+
+    The info field specifies which information userspace wants to get or set
+    using this interface.  Currently we support the following info values:
+
+      VGIC_LEVEL_INFO_LINE_LEVEL:
+	Get/Set the input level of the IRQ line for a set of 32 contiguously
+	numbered interrupts.
+	vINTID must be a multiple of 32.
+
+	kvm_device_attr.addr points to a __u32 value which will contain a
+	bitmap where a set bit means the interrupt level is asserted.
+
+	Bit[n] indicates the status for interrupt vINTID + n.
+
+    SGIs and any interrupt with a higher ID than the number of interrupts
+    supported, will be RAZ/WI.  LPIs are always edge-triggered and are
+    therefore not supported by this interface.
+
+    PPIs are reported per VCPU as specified in the mpidr field, and SPIs are
+    reported with the same value regardless of the mpidr specified.
+
+    The mpidr field encodes the CPU ID based on the affinity information in the
+    architecture defined MPIDR, and the field is encoded as follows:
+      | 63 .... 56 | 55 .... 48 | 47 .... 40 | 39 .... 32 |
+      |    Aff3    |    Aff2    |    Aff1    |    Aff0    |
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt
index 89182f8..76e61c8 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic.txt
@@ -1,24 +1,19 @@
-ARM Virtual Generic Interrupt Controller (VGIC)
-===============================================
+ARM Virtual Generic Interrupt Controller v2 (VGIC)
+==================================================
 
 Device types supported:
   KVM_DEV_TYPE_ARM_VGIC_V2     ARM Generic Interrupt Controller v2.0
-  KVM_DEV_TYPE_ARM_VGIC_V3     ARM Generic Interrupt Controller v3.0
-  KVM_DEV_TYPE_ARM_VGIC_ITS    ARM Interrupt Translation Service Controller
 
-Only one VGIC instance of the V2/V3 types above may be instantiated through
-either this API or the legacy KVM_CREATE_IRQCHIP api.  The created VGIC will
-act as the VM interrupt controller, requiring emulated user-space devices to
-inject interrupts to the VGIC instead of directly to CPUs.
+Only one VGIC instance may be instantiated through either this API or the
+legacy KVM_CREATE_IRQCHIP API.  The created VGIC will act as the VM interrupt
+controller, requiring emulated user-space devices to inject interrupts to the
+VGIC instead of directly to CPUs.
 
-Creating a guest GICv3 device requires a host GICv3 as well.
-GICv3 implementations with hardware compatibility support allow a guest GICv2
-as well.
+GICv3 implementations with hardware compatibility support allow creating a
+guest GICv2 through this interface.  For information on creating a guest GICv3
+device and guest ITS devices, see arm-vgic-v3.txt.  It is not possible to
+create both a GICv3 and GICv2 device on the same VM.
 
-Creating a virtual ITS controller requires a host GICv3 (but does not depend
-on having physical ITS controllers).
-There can be multiple ITS controllers per guest, each of them has to have
-a separate, non-overlapping MMIO region.
 
 Groups:
   KVM_DEV_ARM_VGIC_GRP_ADDR
@@ -32,26 +27,13 @@ Groups:
       Base address in the guest physical address space of the GIC virtual cpu
       interface register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2.
       This address needs to be 4K aligned and the region covers 4 KByte.
-
-    KVM_VGIC_V3_ADDR_TYPE_DIST (rw, 64-bit)
-      Base address in the guest physical address space of the GICv3 distributor
-      register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
-      This address needs to be 64K aligned and the region covers 64 KByte.
-
-    KVM_VGIC_V3_ADDR_TYPE_REDIST (rw, 64-bit)
-      Base address in the guest physical address space of the GICv3
-      redistributor register mappings. There are two 64K pages for each
-      VCPU and all of the redistributor pages are contiguous.
-      Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
-      This address needs to be 64K aligned.
-
-    KVM_VGIC_V3_ADDR_TYPE_ITS (rw, 64-bit)
-      Base address in the guest physical address space of the GICv3 ITS
-      control register frame. The ITS allows MSI(-X) interrupts to be
-      injected into guests. This extension is optional. If the kernel
-      does not support the ITS, the call returns -ENODEV.
-      Only valid for KVM_DEV_TYPE_ARM_VGIC_ITS.
-      This address needs to be 64K aligned and the region covers 128K.
+  Errors:
+    -E2BIG:  Address outside of addressable IPA range
+    -EINVAL: Incorrectly aligned address
+    -EEXIST: Address already configured
+    -ENXIO:  The group or attribute is unknown/unsupported for this device
+             or hardware support is missing.
+    -EFAULT: Invalid user pointer for attr->addr.
 
   KVM_DEV_ARM_VGIC_GRP_DIST_REGS
   Attributes:
-- 
2.9.0

^ permalink raw reply related

* [PULL 00/50] KVM/ARM Changes for v4.9
From: Christoffer Dall @ 2016-09-27 18:05 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Paolo and Radim,

Here are the KVM/ARM Changes for v4.9. They include:

 - Various cleanups and removal of redundant code
 - Two important fixes for not using an in-kernel irqchip
 - A bit of optimizations
 - Handle SError exceptions and present them to guests if appropriate
 - Proxying of GICV access at EL2 if guest mappings are unsafe
 - GICv3 on AArch32 on ARMv8
 - Preparations for GICv3 save/restore, including ABI docs


The following changes since commit 9ac7e3e815060efdc86b6d12448200e3c3597e01:

  KVM: nVMX: expose INS/OUTS information support (2016-09-07 19:34:30 +0200)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-for-v4.9

for you to fetch changes up to 0099b7701f5296a758d9e6b945ec96f96847cc2f:

  KVM: arm/arm64: vgic: Don't flush/sync without a working vgic (2016-09-27 18:57:35 +0200)

Thanks,
-Christoffer

---

Christoffer Dall (6):
      KVM: arm/arm64: Add VGICv3 save/restore API documentation
      KVM: arm/arm64: Factor out vgic_attr_regs_access functionality
      KVM: arm/arm64: Rename vgic_attr_regs_access to vgic_attr_regs_access_v2
      KVM: arm/arm64: Get rid of exported aliases to static functions
      KVM: arm64: Require in-kernel irqchip for PMU support
      KVM: arm/arm64: vgic: Don't flush/sync without a working vgic

Marc Zyngier (28):
      KVM: arm: vgic: Drop build compatibility hack for older kernel versions
      arm64: KVM: Move kvm_vcpu_get_condition out of emulate.c
      arm64: KVM: Move the AArch32 conditional execution to common code
      arm: KVM: Use common AArch32 conditional execution code
      arm64: KVM: Make kvm_skip_instr32 available to HYP
      arm64: KVM: vgic-v2: Add the GICV emulation infrastructure
      arm64: KVM: vgic-v2: Add GICV access from HYP
      arm64: KVM: vgic-v2: Enable GICV access from HYP if access from guest is unsafe
      arm64: KVM: Rename HCR_VA to HCR_VSE
      arm64: KVM: Preserve pending vSError in world switch
      arm64: KVM: Add Virtual Abort injection helper
      arm64: KVM: Add exception code to report EL1 asynchronous aborts
      arm64: KVM: Add EL1 async abort handler
      arm64: KVM: Route asynchronous aborts
      arm64: KVM: Allow an exit code to be tagged with an SError
      arm64: KVM: Inject a Virtual SError if it was pending
      arm64: KVM: Handle async aborts delivered while at EL2
      arm: KVM: Preserve pending Virtual Abort in world switch
      arm: KVM: Add Virtual Abort injection helper
      arm: KVM: Add HYP async abort handler
      arm: KVM: Allow an exit code to be tagged with a Virtual Abort
      arm: KVM: Handle async aborts delivered while at HYP
      arm: KVM: Inject a Virtual Abort if it was pending
      arm: KVM: Drop unreachable HYP abort handlers
      arm/arm64: KVM: Inject virtual abort when guest exits on external abort
      arm/arm64: KVM: Remove external abort test from MMIO handling
      arm64: KVM: Inject a vSerror if detecting a bad GICV access at EL2
      ARM: gic-v3: Work around definition of gic_write_bpr1

Mark Rutland (2):
      arm/kvm: excise redundant cache maintenance
      arm64/kvm: remove unused stub functions

Paolo Bonzini (1):
      KVM: ARM: cleanup kvm_timer_hyp_init

Shanker Donthineni (1):
      arm64: KVM: Optimize __guest_enter/exit() to save a few instructions

Vladimir Murzin (12):
      arm64: KVM: VHE: reset PSTATE.PAN on entry to EL2
      arm64: KVM: Use static keys for selecting the GIC backend
      arm64: KVM: Move GIC accessors to arch_gicv3.h
      arm64: KVM: Move vgic-v3 save/restore to virt/kvm/arm/hyp
      KVM: arm64: vgic-its: Introduce config option to guard ITS specific code
      KVM: arm: vgic: Fix compiler warnings when built for 32-bit
      KVM: arm: vgic: Support 64-bit data manipulation on 32-bit host systems
      ARM: Introduce MPIDR_LEVEL_SHIFT macro
      ARM: Move system register accessors to asm/cp15.h
      ARM: gic-v3: Introduce 32-to-64-bit mappings for GICv3 cpu registers
      ARM: KVM: Support vgic-v3
      arm64: KVM: Remove duplicating init code for setting VMID

 Documentation/virtual/kvm/devices/arm-vgic-its.txt |  38 ++++
 Documentation/virtual/kvm/devices/arm-vgic-v3.txt  | 206 +++++++++++++++++++++
 Documentation/virtual/kvm/devices/arm-vgic.txt     |  52 ++----
 Documentation/virtual/kvm/devices/vcpu.txt         |   4 +-
 arch/arm/include/asm/arch_gicv3.h                  | 100 ++++++++--
 arch/arm/include/asm/cp15.h                        |  15 ++
 arch/arm/include/asm/cputype.h                     |   1 +
 arch/arm/include/asm/kvm_asm.h                     |   7 +
 arch/arm/include/asm/kvm_emulate.h                 |  35 +++-
 arch/arm/include/asm/kvm_host.h                    |   5 +
 arch/arm/include/asm/kvm_hyp.h                     |  18 +-
 arch/arm/include/asm/kvm_mmu.h                     |  28 +--
 arch/arm/include/uapi/asm/kvm.h                    |   7 +
 arch/arm/kvm/Makefile                              |   3 +
 arch/arm/kvm/arm.c                                 |  12 +-
 arch/arm/kvm/coproc.c                              |  35 ++++
 arch/arm/kvm/emulate.c                             | 111 ++---------
 arch/arm/kvm/handle_exit.c                         |  49 +++--
 arch/arm/kvm/hyp/Makefile                          |   1 +
 arch/arm/kvm/hyp/entry.S                           |  31 ++++
 arch/arm/kvm/hyp/hyp-entry.S                       |  16 +-
 arch/arm/kvm/hyp/switch.c                          |  25 ++-
 arch/arm/kvm/hyp/tlb.c                             |  15 +-
 arch/arm/kvm/mmio.c                                |   6 -
 arch/arm/kvm/mmu.c                                 |   7 +-
 arch/arm64/include/asm/arch_gicv3.h                |  13 ++
 arch/arm64/include/asm/kvm_arm.h                   |   4 +-
 arch/arm64/include/asm/kvm_asm.h                   |   9 +-
 arch/arm64/include/asm/kvm_emulate.h               |  11 ++
 arch/arm64/include/asm/kvm_hyp.h                   |   1 +
 arch/arm64/include/asm/kvm_mmu.h                   |   6 -
 arch/arm64/kvm/Kconfig                             |   4 +-
 arch/arm64/kvm/Makefile                            |   3 +-
 arch/arm64/kvm/handle_exit.c                       |  23 +++
 arch/arm64/kvm/hyp/Makefile                        |   2 +-
 arch/arm64/kvm/hyp/debug-sr.c                      |   4 +-
 arch/arm64/kvm/hyp/entry.S                         | 128 ++++++++-----
 arch/arm64/kvm/hyp/hyp-entry.S                     |  73 +++++---
 arch/arm64/kvm/hyp/switch.c                        |  84 +++++++--
 arch/arm64/kvm/hyp/tlb.c                           |  13 +-
 arch/arm64/kvm/inject_fault.c                      |  12 ++
 include/kvm/arm_vgic.h                             |  18 +-
 arch/arm64/kvm/emulate.c => virt/kvm/arm/aarch32.c |  25 +--
 virt/kvm/arm/arch_timer.c                          |   6 +-
 virt/kvm/arm/hyp/vgic-v2-sr.c                      |  57 ++++++
 {arch/arm64/kvm => virt/kvm/arm}/hyp/vgic-v3-sr.c  |  17 +-
 virt/kvm/arm/pmu.c                                 |   8 +
 virt/kvm/arm/vgic/vgic-init.c                      |   4 +
 virt/kvm/arm/vgic/vgic-irqfd.c                     |   6 -
 virt/kvm/arm/vgic/vgic-kvm-device.c                | 133 ++++++++-----
 virt/kvm/arm/vgic/vgic-mmio-v3.c                   |   8 +-
 virt/kvm/arm/vgic/vgic-mmio.c                      |   2 -
 virt/kvm/arm/vgic/vgic-mmio.h                      |   4 +-
 virt/kvm/arm/vgic/vgic-v2.c                        |  71 ++++---
 virt/kvm/arm/vgic/vgic.c                           |   8 +-
 virt/kvm/arm/vgic/vgic.h                           |  54 +-----
 56 files changed, 1076 insertions(+), 562 deletions(-)
 create mode 100644 Documentation/virtual/kvm/devices/arm-vgic-its.txt
 create mode 100644 Documentation/virtual/kvm/devices/arm-vgic-v3.txt
 rename arch/arm64/kvm/emulate.c => virt/kvm/arm/aarch32.c (90%)
 rename {arch/arm64/kvm => virt/kvm/arm}/hyp/vgic-v3-sr.c (94%)

^ permalink raw reply


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