From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1CC4C4332F for ; Thu, 11 Nov 2021 02:08:05 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 634D0619E1 for ; Thu, 11 Nov 2021 02:08:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 634D0619E1 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 152FB4B25B; Wed, 10 Nov 2021 21:08:05 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@google.com Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jxo18AGvrEJS; Wed, 10 Nov 2021 21:08:03 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4219F4B260; Wed, 10 Nov 2021 21:08:03 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A86DD4B15A for ; Wed, 10 Nov 2021 21:08:02 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id wnmVy1jfxNoy for ; Wed, 10 Nov 2021 21:08:01 -0500 (EST) Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id BDCE24B25C for ; Wed, 10 Nov 2021 21:07:59 -0500 (EST) Received: by mail-pf1-f201.google.com with SMTP id k63-20020a628442000000b004812ea67c34so3074787pfd.2 for ; Wed, 10 Nov 2021 18:07:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=BFR/1q5iLt3yf5kWLtXoY89YerPRd53Fbf8elisWPU4=; b=EyJdNG55YlgiJw0AhwmBWiBKFN2bqclVs6tFme/MMuM8bhcjKJQBF0OcoJBKQN4Yga axZl4D8H01llZcE+B1lMipS7te9ff2VOp7tm63SOZ0bYgRPgOvv7dz7am2CWgxpg0t7P MNRfZq3ijQaVJG2uCad7xkxWh1HPBFRFulQ+NTiiERVK6s/+qvvEEXRWQscxLcYr8ons RAPjBHbZ9nw0KZopTSMI8rlJItEVAXh71vLtMjT3aiL6FIEsbFQlPdO+7CY5ZUb3d8zc 4THP+pE5BT9GJwVdJXE8nIpJ82zKI4sbu9siyG5CLHKeyWKTSNq0cqo3I766dA0RjB8y OjyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=BFR/1q5iLt3yf5kWLtXoY89YerPRd53Fbf8elisWPU4=; b=nvVpG3mPPs3j5WhV90L5+uRJi2JjFrwLL6ocDCoarVxsCA2lI43b7wipJh+sd4RrFl PT59DhTWGdI9e1lRULwdVMZYP22468QwsF1UNltM1CPKakdk4ktBra8L5nPngu0fHwJJ s7OhAujIalM/bBgKNxOmgzhIMm4appfaMEDir5kYY+IKT6l7UVX7MIkTYottjWsS4U64 cKJh9xNRO3olXfzmfun7ne+MyL7b99eWyf+ost0zUUr9dkOIc6HpsI3hHzdHgOgvFvJL dKBhZsBdTkWSOv+oY1VksveHb95VrLQTxvTDFjwQYSt3sk29GHftW9sKCDqLn3s78LNA F11Q== X-Gm-Message-State: AOAM531USy0hnKmChedKrkqsp6+pe8QFDPIhQ18lhGFYcO9xTg0rDQlh BxWs9Fx+Jw+3XOZkTwQ2bwVaGCxAGRw= X-Google-Smtp-Source: ABdhPJzd8hxvmP15QQtACiUYvwIBDjhv9tE00/OdnnHyX3h6LjesiRmUGTAqyb2RSiJlII09jv6jyEbG1Qo= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a17:90a:c403:: with SMTP id i3mr23027931pjt.203.1636596478856; Wed, 10 Nov 2021 18:07:58 -0800 (PST) Date: Thu, 11 Nov 2021 02:07:32 +0000 In-Reply-To: <20211111020738.2512932-1-seanjc@google.com> Message-Id: <20211111020738.2512932-12-seanjc@google.com> Mime-Version: 1.0 References: <20211111020738.2512932-1-seanjc@google.com> X-Mailer: git-send-email 2.34.0.rc0.344.g81b53c2807-goog Subject: [PATCH v4 11/17] KVM: x86: More precisely identify NMI from guest when handling PMI From: Sean Christopherson To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Will Deacon , Mark Rutland , Russell King , Marc Zyngier , Catalin Marinas , Guo Ren , Nick Hu , Greentime Hu , Vincent Chen , Paul Walmsley , Palmer Dabbelt , Albert Ou , Thomas Gleixner , Borislav Petkov , Dave Hansen , x86@kernel.org, Paolo Bonzini , Boris Ostrovsky , Juergen Gross Cc: Wanpeng Li , kvm@vger.kernel.org, Alexander Shishkin , "H. Peter Anvin" , linux-riscv@lists.infradead.org, Jiri Olsa , kvmarm@lists.cs.columbia.edu, Stefano Stabellini , Like Xu , Joerg Roedel , linux-csky@vger.kernel.org, xen-devel@lists.xenproject.org, Zhu Lingshan , Namhyung Kim , Artem Kashkanov , linux-arm-kernel@lists.infradead.org, Jim Mattson , Like Xu , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Vitaly Kuznetsov X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list Reply-To: Sean Christopherson List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Differentiate between IRQ and NMI for KVM's PMC overflow callback, which was originally invoked in response to an NMI that arrived while the guest was running, but was inadvertantly changed to fire on IRQs as well when support for perf without PMU/NMI was added to KVM. In practice, this should be a nop as the PMC overflow callback shouldn't be reached, but it's a cheap and easy fix that also better documents the situation. Note, this also doesn't completely prevent false positives if perf somehow ends up calling into KVM, e.g. an NMI can arrive in host after KVM sets its flag. Fixes: dd60d217062f ("KVM: x86: Fix perf timer mode IP reporting") Reviewed-by: Paolo Bonzini Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/svm.c | 2 +- arch/x86/kvm/vmx/vmx.c | 4 +++- arch/x86/kvm/x86.c | 2 +- arch/x86/kvm/x86.h | 13 ++++++++++--- 4 files changed, 15 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index b36ca4e476c2..df6a3e0bdcde 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -3936,7 +3936,7 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu) } if (unlikely(svm->vmcb->control.exit_code == SVM_EXIT_NMI)) - kvm_before_interrupt(vcpu); + kvm_before_interrupt(vcpu, KVM_HANDLING_NMI); kvm_load_host_xsave_state(vcpu); stgi(); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0927d07b2efb..36098eb9a7f9 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6371,7 +6371,9 @@ void vmx_do_interrupt_nmi_irqoff(unsigned long entry); static void handle_interrupt_nmi_irqoff(struct kvm_vcpu *vcpu, unsigned long entry) { - kvm_before_interrupt(vcpu); + bool is_nmi = entry == (unsigned long)asm_exc_nmi_noist; + + kvm_before_interrupt(vcpu, is_nmi ? KVM_HANDLING_NMI : KVM_HANDLING_IRQ); vmx_do_interrupt_nmi_irqoff(entry); kvm_after_interrupt(vcpu); } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c8ef49385c99..e9e1a4bb1d00 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9837,7 +9837,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) * interrupts on processors that implement an interrupt shadow, the * stat.exits increment will do nicely. */ - kvm_before_interrupt(vcpu); + kvm_before_interrupt(vcpu, KVM_HANDLING_IRQ); local_irq_enable(); ++vcpu->stat.exits; local_irq_disable(); diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index d070043fd2e8..f8d2c58feadc 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -385,9 +385,16 @@ static inline bool kvm_cstate_in_guest(struct kvm *kvm) return kvm->arch.cstate_in_guest; } -static inline void kvm_before_interrupt(struct kvm_vcpu *vcpu) +enum kvm_intr_type { + /* Values are arbitrary, but must be non-zero. */ + KVM_HANDLING_IRQ = 1, + KVM_HANDLING_NMI, +}; + +static inline void kvm_before_interrupt(struct kvm_vcpu *vcpu, + enum kvm_intr_type intr) { - WRITE_ONCE(vcpu->arch.handling_intr_from_guest, 1); + WRITE_ONCE(vcpu->arch.handling_intr_from_guest, (u8)intr); } static inline void kvm_after_interrupt(struct kvm_vcpu *vcpu) @@ -397,7 +404,7 @@ static inline void kvm_after_interrupt(struct kvm_vcpu *vcpu) static inline bool kvm_handling_nmi_from_guest(struct kvm_vcpu *vcpu) { - return !!vcpu->arch.handling_intr_from_guest; + return vcpu->arch.handling_intr_from_guest == KVM_HANDLING_NMI; } static inline bool kvm_pat_valid(u64 data) -- 2.34.0.rc0.344.g81b53c2807-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm