From: David Brazdil <dbrazdil@google.com>
To: kvmarm@lists.cs.columbia.edu
Cc: Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>,
James Morse <james.morse@arm.com>,
Julien Thierry <julien.thierry.kdev@gmail.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Dennis Zhou <dennis@kernel.org>, Tejun Heo <tj@kernel.org>,
Christoph Lameter <cl@linux.com>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, kernel-team@android.com,
David Brazdil <dbrazdil@google.com>,
Andrew Scull <ascull@google.com>
Subject: [PATCH v4 04/10] kvm: arm64: Remove __hyp_this_cpu_read
Date: Tue, 22 Sep 2020 21:49:04 +0100 [thread overview]
Message-ID: <20200922204910.7265-5-dbrazdil@google.com> (raw)
In-Reply-To: <20200922204910.7265-1-dbrazdil@google.com>
this_cpu_ptr is meant for use in kernel proper because it selects between
TPIDR_EL1/2 based on nVHE/VHE. __hyp_this_cpu_ptr was used in hyp to always
select TPIDR_EL2. Unify all users behind this_cpu_ptr and friends by
selecting _EL2 register under __KVM_NVHE_HYPERVISOR__. VHE continues
selecting the register using alternatives.
Under CONFIG_DEBUG_PREEMPT, the kernel helpers perform a preemption check
which is omitted by the hyp helpers. Preserve the behavior for nVHE by
overriding the corresponding macros under __KVM_NVHE_HYPERVISOR__. Extend
the checks into VHE hyp code.
Acked-by: Andrew Scull <ascull@google.com>
Signed-off-by: David Brazdil <dbrazdil@google.com>
---
arch/arm64/include/asm/kvm_asm.h | 20 ----------------
arch/arm64/include/asm/percpu.h | 28 +++++++++++++++++++++--
arch/arm64/kvm/hyp/include/hyp/debug-sr.h | 4 ++--
arch/arm64/kvm/hyp/include/hyp/switch.h | 8 +++----
arch/arm64/kvm/hyp/nvhe/switch.c | 2 +-
arch/arm64/kvm/hyp/vhe/switch.c | 2 +-
arch/arm64/kvm/hyp/vhe/sysreg-sr.c | 4 ++--
7 files changed, 36 insertions(+), 32 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index c085032e2e3e..c196eec25498 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -143,26 +143,6 @@ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ];
addr; \
})
-/*
- * Home-grown __this_cpu_{ptr,read} variants that always work at HYP,
- * provided that sym is really a *symbol* and not a pointer obtained from
- * a data structure. As for SHIFT_PERCPU_PTR(), the creative casting keeps
- * sparse quiet.
- */
-#define __hyp_this_cpu_ptr(sym) \
- ({ \
- void *__ptr; \
- __verify_pcpu_ptr(&sym); \
- __ptr = hyp_symbol_addr(sym); \
- __ptr += read_sysreg(tpidr_el2); \
- (typeof(sym) __kernel __force *)__ptr; \
- })
-
-#define __hyp_this_cpu_read(sym) \
- ({ \
- *__hyp_this_cpu_ptr(sym); \
- })
-
#define __KVM_EXTABLE(from, to) \
" .pushsection __kvm_ex_table, \"a\"\n" \
" .align 3\n" \
diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h
index 0b6409b89e5e..1599e17379d8 100644
--- a/arch/arm64/include/asm/percpu.h
+++ b/arch/arm64/include/asm/percpu.h
@@ -19,7 +19,16 @@ static inline void set_my_cpu_offset(unsigned long off)
:: "r" (off) : "memory");
}
-static inline unsigned long __my_cpu_offset(void)
+static inline unsigned long __hyp_my_cpu_offset(void)
+{
+ /*
+ * Non-VHE hyp code runs with preemption disabled. No need to hazard
+ * the register access against barrier() as in __kern_my_cpu_offset.
+ */
+ return read_sysreg(tpidr_el2);
+}
+
+static inline unsigned long __kern_my_cpu_offset(void)
{
unsigned long off;
@@ -35,7 +44,12 @@ static inline unsigned long __my_cpu_offset(void)
return off;
}
-#define __my_cpu_offset __my_cpu_offset()
+
+#ifdef __KVM_NVHE_HYPERVISOR__
+#define __my_cpu_offset __hyp_my_cpu_offset()
+#else
+#define __my_cpu_offset __kern_my_cpu_offset()
+#endif
#define PERCPU_RW_OPS(sz) \
static inline unsigned long __percpu_read_##sz(void *ptr) \
@@ -227,4 +241,14 @@ PERCPU_RET_OP(add, add, ldadd)
#include <asm-generic/percpu.h>
+/* Redefine macros for nVHE hyp under DEBUG_PREEMPT to avoid its dependencies. */
+#if defined(__KVM_NVHE_HYPERVISOR__) && defined(CONFIG_DEBUG_PREEMPT)
+#undef this_cpu_ptr
+#define this_cpu_ptr raw_cpu_ptr
+#undef __this_cpu_read
+#define __this_cpu_read raw_cpu_read
+#undef __this_cpu_write
+#define __this_cpu_write raw_cpu_write
+#endif
+
#endif /* __ASM_PERCPU_H */
diff --git a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h
index 5e28ea6aa097..4ebe9f558f3a 100644
--- a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h
+++ b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h
@@ -135,7 +135,7 @@ static inline void __debug_switch_to_guest_common(struct kvm_vcpu *vcpu)
if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
return;
- host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
@@ -154,7 +154,7 @@ static inline void __debug_switch_to_host_common(struct kvm_vcpu *vcpu)
if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
return;
- host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 5b6b8fa00f0a..f150407fa798 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -386,7 +386,7 @@ static inline bool __hyp_handle_ptrauth(struct kvm_vcpu *vcpu)
!esr_is_ptrauth_trap(kvm_vcpu_get_esr(vcpu)))
return false;
- ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
__ptrauth_save_key(ctxt, APIA);
__ptrauth_save_key(ctxt, APIB);
__ptrauth_save_key(ctxt, APDA);
@@ -495,7 +495,7 @@ static inline void __set_guest_arch_workaround_state(struct kvm_vcpu *vcpu)
* guest wants it disabled, so be it...
*/
if (__needs_ssbd_off(vcpu) &&
- __hyp_this_cpu_read(arm64_ssbd_callback_required))
+ __this_cpu_read(arm64_ssbd_callback_required))
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL);
#endif
}
@@ -507,7 +507,7 @@ static inline void __set_host_arch_workaround_state(struct kvm_vcpu *vcpu)
* If the guest has disabled the workaround, bring it back on.
*/
if (__needs_ssbd_off(vcpu) &&
- __hyp_this_cpu_read(arm64_ssbd_callback_required))
+ __this_cpu_read(arm64_ssbd_callback_required))
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL);
#endif
}
@@ -521,7 +521,7 @@ static inline void __kvm_unexpected_el2_exception(void)
entry = hyp_symbol_addr(__start___kvm_ex_table);
end = hyp_symbol_addr(__stop___kvm_ex_table);
- host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
while (entry < end) {
addr = (unsigned long)&entry->insn + entry->insn;
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index 0970442d2dbc..cc4f8e790fb3 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -175,7 +175,7 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
vcpu = kern_hyp_va(vcpu);
- host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
host_ctxt->__hyp_running_vcpu = vcpu;
guest_ctxt = &vcpu->arch.ctxt;
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index c1da4f86ccac..575e8054f116 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -108,7 +108,7 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *guest_ctxt;
u64 exit_code;
- host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
host_ctxt->__hyp_running_vcpu = vcpu;
guest_ctxt = &vcpu->arch.ctxt;
diff --git a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c
index 996471e4c138..2a0b8c88d74f 100644
--- a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c
@@ -66,7 +66,7 @@ void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt;
struct kvm_cpu_context *host_ctxt;
- host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
__sysreg_save_user_state(host_ctxt);
/*
@@ -100,7 +100,7 @@ void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt;
struct kvm_cpu_context *host_ctxt;
- host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
deactivate_traps_vhe_put();
__sysreg_save_el1_state(guest_ctxt);
--
2.28.0.681.g6f77f65b4e-goog
next prev parent reply other threads:[~2020-09-22 20:49 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-22 20:49 [PATCH v4 00/10] Independent per-CPU data section for nVHE David Brazdil
2020-09-22 20:49 ` [PATCH v4 01/10] kvm: arm64: Partially link nVHE hyp code, simplify HYPCOPY David Brazdil
2020-09-22 20:49 ` [PATCH v4 02/10] kvm: arm64: Move nVHE hyp namespace macros to hyp_image.h David Brazdil
2020-09-22 20:49 ` [PATCH v4 03/10] kvm: arm64: Only define __kvm_ex_table for CONFIG_KVM David Brazdil
2020-09-22 20:49 ` David Brazdil [this message]
2020-09-29 17:30 ` [PATCH v4 04/10] kvm: arm64: Remove __hyp_this_cpu_read Will Deacon
2020-09-22 20:49 ` [PATCH v4 05/10] kvm: arm64: Remove hyp_adr/ldr_this_cpu David Brazdil
2020-09-29 17:34 ` Will Deacon
2020-09-29 17:46 ` Marc Zyngier
2020-09-22 20:49 ` [PATCH v4 06/10] kvm: arm64: Add helpers for accessing nVHE hyp per-cpu vars David Brazdil
2020-09-22 20:49 ` [PATCH v4 07/10] kvm: arm64: Duplicate arm64_ssbd_callback_required for nVHE hyp David Brazdil
2020-09-29 17:37 ` Will Deacon
2020-09-22 20:49 ` [PATCH v4 08/10] kvm: arm64: Create separate instances of kvm_host_data for VHE/nVHE David Brazdil
2020-09-22 20:49 ` [PATCH v4 09/10] kvm: arm64: Set up hyp percpu data for nVHE David Brazdil
2020-09-29 17:50 ` Will Deacon
2020-09-22 20:49 ` [PATCH v4 10/10] kvm: arm64: Remove unnecessary hyp mappings David Brazdil
2020-09-29 17:49 ` Will Deacon
2020-09-24 10:10 ` [PATCH v4 00/10] Independent per-CPU data section for nVHE Christopher Lameter
2020-10-02 8:19 ` Marc Zyngier
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200922204910.7265-5-dbrazdil@google.com \
--to=dbrazdil@google.com \
--cc=ascull@google.com \
--cc=catalin.marinas@arm.com \
--cc=cl@linux.com \
--cc=dennis@kernel.org \
--cc=james.morse@arm.com \
--cc=julien.thierry.kdev@gmail.com \
--cc=kernel-team@android.com \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=maz@kernel.org \
--cc=suzuki.poulose@arm.com \
--cc=tj@kernel.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox