The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f4b027c5c8199abd4fb6f00d67d380548dbfdfa8 Mon Sep 17 00:00:00 2001 From: Sean Christopherson seanjc@google.com Date: Thu, 11 Nov 2021 02:07:24 +0000 Subject: [PATCH] KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest
Override the Processor Trace (PT) interrupt handler for guest mode if and only if PT is configured for host+guest mode, i.e. is being used independently by both host and guest. If PT is configured for system mode, the host fully controls PT and must handle all events.
Fixes: 8479e04e7d6b ("KVM: x86: Inject PMI for KVM guest") Reported-by: Alexander Shishkin alexander.shishkin@linux.intel.com Reported-by: Artem Kashkanov artem.kashkanov@intel.com Signed-off-by: Sean Christopherson seanjc@google.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Acked-by: Paolo Bonzini pbonzini@redhat.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20211111020738.2512932-4-seanjc@google.com
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index e5d8700319cc..41e858df5795 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1516,6 +1516,7 @@ struct kvm_x86_init_ops { int (*disabled_by_bios)(void); int (*check_processor_compatibility)(void); int (*hardware_setup)(void); + bool (*intel_pt_intr_in_guest)(void);
struct kvm_x86_ops *runtime_ops; }; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index ba66c171d951..7d90c8d443ac 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7865,6 +7865,7 @@ static struct kvm_x86_init_ops vmx_init_ops __initdata = { .disabled_by_bios = vmx_disabled_by_bios, .check_processor_compatibility = vmx_check_processor_compat, .hardware_setup = hardware_setup, + .intel_pt_intr_in_guest = vmx_pt_mode_is_host_guest,
.runtime_ops = &vmx_x86_ops, }; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 50f0cd16f2d4..760c4e3a8326 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8510,7 +8510,7 @@ static struct perf_guest_info_callbacks kvm_guest_cbs = { .is_in_guest = kvm_is_in_guest, .is_user_mode = kvm_is_user_mode, .get_guest_ip = kvm_get_guest_ip, - .handle_intel_pt_intr = kvm_handle_intel_pt_intr, + .handle_intel_pt_intr = NULL, };
#ifdef CONFIG_X86_64 @@ -11222,6 +11222,8 @@ int kvm_arch_hardware_setup(void *opaque) memcpy(&kvm_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops)); kvm_ops_static_call_update();
+ if (ops->intel_pt_intr_in_guest && ops->intel_pt_intr_in_guest()) + kvm_guest_cbs.handle_intel_pt_intr = kvm_handle_intel_pt_intr; perf_register_guest_info_callbacks(&kvm_guest_cbs);
if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES)) @@ -11252,6 +11254,7 @@ int kvm_arch_hardware_setup(void *opaque) void kvm_arch_hardware_unsetup(void) { perf_unregister_guest_info_callbacks(&kvm_guest_cbs); + kvm_guest_cbs.handle_intel_pt_intr = NULL;
static_call(kvm_x86_hardware_unsetup)(); }