From 7d14919c0d475a795c0127631ac8ecb2b0f31831 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 23 Aug 2018 11:51:43 +0100 Subject: arm64: KVM: Only force FPEXC32_EL2.EN if trapping FPSIMD If trapping FPSIMD in the context of an AArch32 guest, it is critical to set FPEXC32_EL2.EN to 1 so that the trapping is taken to EL2 and not EL1. Conversely, it is just as critical *not* to set FPEXC32_EL2.EN to 1 if we're not going to trap FPSIMD, as we then corrupt the existing VFP state. Moving the call to __activate_traps_fpsimd32 to the point where we know for sure that we are going to trap ensures that we don't set that bit spuriously. Fixes: e6b673b741ea ("KVM: arm64: Optimise FPSIMD handling to reduce guest/host thrashing") Cc: stable@vger.kernel.org # v4.18 Cc: Dave Martin Reported-by: Alexander Graf Tested-by: Alexander Graf Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm64/kvm/hyp/switch.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index d496ef579859..ca46153d7915 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -98,8 +98,10 @@ static void activate_traps_vhe(struct kvm_vcpu *vcpu) val = read_sysreg(cpacr_el1); val |= CPACR_EL1_TTA; val &= ~CPACR_EL1_ZEN; - if (!update_fp_enabled(vcpu)) + if (!update_fp_enabled(vcpu)) { val &= ~CPACR_EL1_FPEN; + __activate_traps_fpsimd32(vcpu); + } write_sysreg(val, cpacr_el1); @@ -114,8 +116,10 @@ static void __hyp_text __activate_traps_nvhe(struct kvm_vcpu *vcpu) val = CPTR_EL2_DEFAULT; val |= CPTR_EL2_TTA | CPTR_EL2_TZ; - if (!update_fp_enabled(vcpu)) + if (!update_fp_enabled(vcpu)) { val |= CPTR_EL2_TFP; + __activate_traps_fpsimd32(vcpu); + } write_sysreg(val, cptr_el2); } @@ -129,7 +133,6 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE)) write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2); - __activate_traps_fpsimd32(vcpu); if (has_vhe()) activate_traps_vhe(vcpu); else -- cgit v1.2.3-59-g8ed1b From a35381e10dc46dd75e65e4b3832d9a0005d48d44 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 23 Aug 2018 10:18:14 +0100 Subject: KVM: Remove obsolete kvm_unmap_hva notifier backend kvm_unmap_hva is long gone, and we only have kvm_unmap_hva_range to deal with. Drop the now obsolete code. Fixes: fb1522e099f0 ("KVM: update to new mmu_notifier semantic v2") Cc: James Hogan Reviewed-by: Paolo Bonzini Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/include/asm/kvm_host.h | 1 - arch/arm64/include/asm/kvm_host.h | 1 - arch/mips/include/asm/kvm_host.h | 1 - arch/mips/kvm/mmu.c | 10 ---------- arch/x86/include/asm/kvm_host.h | 1 - arch/x86/kvm/mmu.c | 5 ----- virt/kvm/arm/mmu.c | 12 ------------ virt/kvm/arm/trace.h | 15 --------------- 8 files changed, 46 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 79906cecb091..3ad482d2f1eb 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -223,7 +223,6 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, struct kvm_vcpu_events *events); #define KVM_ARCH_WANT_MMU_NOTIFIER -int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end); void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index f26055f2306e..8e6d46df38aa 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -357,7 +357,6 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, struct kvm_vcpu_events *events); #define KVM_ARCH_WANT_MMU_NOTIFIER -int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end); void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h index a9af1d2dcd69..2c1c53d12179 100644 --- a/arch/mips/include/asm/kvm_host.h +++ b/arch/mips/include/asm/kvm_host.h @@ -931,7 +931,6 @@ enum kvm_mips_fault_result kvm_trap_emul_gva_fault(struct kvm_vcpu *vcpu, bool write); #define KVM_ARCH_WANT_MMU_NOTIFIER -int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end); void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c index ee64db032793..d8dcdb350405 100644 --- a/arch/mips/kvm/mmu.c +++ b/arch/mips/kvm/mmu.c @@ -512,16 +512,6 @@ static int kvm_unmap_hva_handler(struct kvm *kvm, gfn_t gfn, gfn_t gfn_end, return 1; } -int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) -{ - unsigned long end = hva + PAGE_SIZE; - - handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL); - - kvm_mips_callbacks->flush_shadow_all(kvm); - return 0; -} - int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) { handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL); diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 00ddb0c9e612..e6a33420b871 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1450,7 +1450,6 @@ asmlinkage void kvm_spurious_fault(void); ____kvm_handle_fault_on_reboot(insn, "") #define KVM_ARCH_WANT_MMU_NOTIFIER -int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end); int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end); int kvm_test_age_hva(struct kvm *kvm, unsigned long hva); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index a282321329b5..d440154e8938 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1853,11 +1853,6 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, return kvm_handle_hva_range(kvm, hva, hva + 1, data, handler); } -int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) -{ - return kvm_handle_hva(kvm, hva, 0, kvm_unmap_rmapp); -} - int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) { return kvm_handle_hva_range(kvm, start, end, 0, kvm_unmap_rmapp); diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index 111a660be3be..ed162a6c57c5 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1817,18 +1817,6 @@ static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *dat return 0; } -int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) -{ - unsigned long end = hva + PAGE_SIZE; - - if (!kvm->arch.pgd) - return 0; - - trace_kvm_unmap_hva(hva); - handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL); - return 0; -} - int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) { diff --git a/virt/kvm/arm/trace.h b/virt/kvm/arm/trace.h index e53b596f483b..57b3edebbb40 100644 --- a/virt/kvm/arm/trace.h +++ b/virt/kvm/arm/trace.h @@ -134,21 +134,6 @@ TRACE_EVENT(kvm_mmio_emulate, __entry->vcpu_pc, __entry->instr, __entry->cpsr) ); -TRACE_EVENT(kvm_unmap_hva, - TP_PROTO(unsigned long hva), - TP_ARGS(hva), - - TP_STRUCT__entry( - __field( unsigned long, hva ) - ), - - TP_fast_assign( - __entry->hva = hva; - ), - - TP_printk("mmu notifier unmap hva: %#08lx", __entry->hva) -); - TRACE_EVENT(kvm_unmap_hva_range, TP_PROTO(unsigned long start, unsigned long end), TP_ARGS(start, end), -- cgit v1.2.3-59-g8ed1b From df3190e22016abf74ef67c9691e9fa1012a66bd5 Mon Sep 17 00:00:00 2001 From: Steven Price Date: Mon, 13 Aug 2018 17:04:53 +0100 Subject: arm64: KVM: Remove pgd_lock The lock has never been used and the page tables are protected by mmu_lock in struct kvm. Reviewed-by: Suzuki K Poulose Signed-off-by: Steven Price Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm64/include/asm/kvm_host.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 8e6d46df38aa..3d6d7336f871 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -61,8 +61,7 @@ struct kvm_arch { u64 vmid_gen; u32 vmid; - /* 1-level 2nd stage table and lock */ - spinlock_t pgd_lock; + /* 1-level 2nd stage table, protected by kvm->mmu_lock */ pgd_t *pgd; /* VTTBR value associated with above pgd and vmid */ -- cgit v1.2.3-59-g8ed1b