From: Like Xu <like.xu.linux@gmail.com>
To: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v4 09/12] KVM: x86/pmu: Forget PERFCTR_CORE if the min num of counters isn't met
Date: Tue, 14 Feb 2023 13:07:54 +0800 [thread overview]
Message-ID: <20230214050757.9623-10-likexu@tencent.com> (raw)
In-Reply-To: <20230214050757.9623-1-likexu@tencent.com>
From: Like Xu <likexu@tencent.com>
KVM should sanity check the number of counters enumerated by perf and
explicitly drop PERFCTR_CORE support if the min isn't met. E.g. if KVM
needs 6 counters and perf says there are 4, then something is wrong and
enumerating 6 to the guest is only going to cause more issues.
Opportunistically, the existing kvm_cpu_cap_check_and_set() makes it
easier to simplify the host check before setting the PERFCTR_CORE flag.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Like Xu <likexu@tencent.com>
---
arch/x86/kvm/svm/svm.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index dd21e8b1a259..f4a4691b4f4e 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4910,9 +4910,14 @@ static __init void svm_set_cpu_caps(void)
boot_cpu_has(X86_FEATURE_AMD_SSBD))
kvm_cpu_cap_set(X86_FEATURE_VIRT_SSBD);
- /* AMD PMU PERFCTR_CORE CPUID */
- if (enable_pmu && boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
- kvm_cpu_cap_set(X86_FEATURE_PERFCTR_CORE);
+ if (enable_pmu) {
+ if (kvm_pmu_cap.num_counters_gp < AMD64_NUM_COUNTERS_CORE) {
+ kvm_pmu_cap.num_counters_gp = AMD64_NUM_COUNTERS;
+ } else {
+ /* AMD PMU PERFCTR_CORE CPUID */
+ kvm_cpu_cap_check_and_set(X86_FEATURE_PERFCTR_CORE);
+ }
+ }
/* CPUID 0x8000001F (SME/SEV features) */
sev_set_cpu_caps();
--
2.39.1
next prev parent reply other threads:[~2023-02-14 5:09 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-14 5:07 [PATCH v4 00/12] KVM: x86: Add AMD Guest PerfMonV2 PMU support Like Xu
2023-02-14 5:07 ` [PATCH v4 01/12] KVM: x86/pmu: Rename pmc_is_enabled() to pmc_is_globally_enabled() Like Xu
2023-02-14 5:07 ` [PATCH v4 02/12] KVM: VMX: Refactor intel_pmu_set_msr() to align with other set_msr() helpers Like Xu
2023-02-16 21:13 ` Sean Christopherson
2023-02-21 8:44 ` Like Xu
2023-03-23 7:43 ` Like Xu
2023-03-23 14:28 ` Sean Christopherson
2023-02-14 5:07 ` [PATCH v4 03/12] KVM: x86/pmu: Rewrite reprogram_counters() to improve performance Like Xu
2023-02-14 5:07 ` [PATCH v4 04/12] KVM: x86/pmu: Expose reprogram_counters() in pmu.h Like Xu
2023-02-14 5:07 ` [PATCH v4 05/12] KVM: x86/pmu: Error when user sets the GLOBAL_STATUS reserved bits Like Xu
2023-04-06 23:45 ` Sean Christopherson
2023-04-07 5:08 ` Like Xu
2023-04-07 15:43 ` Sean Christopherson
2023-02-14 5:07 ` [PATCH v4 06/12] KVM: x86/pmu: Make part of the Intel v2 PMU MSRs handling x86 generic Like Xu
2023-04-06 23:57 ` Sean Christopherson
2023-04-07 1:39 ` Sean Christopherson
2023-02-14 5:07 ` [PATCH v4 07/12] KVM: x86/cpuid: Use fast return for cpuid "0xa" leaf when !enable_pmu Like Xu
2023-04-06 23:59 ` Sean Christopherson
2023-02-14 5:07 ` [PATCH v4 08/12] KVM: x86/pmu: Disable vPMU if the minimum num of counters isn't met Like Xu
2023-04-07 0:06 ` Sean Christopherson
2023-04-07 0:23 ` Sean Christopherson
2023-02-14 5:07 ` Like Xu [this message]
2023-04-07 0:32 ` [PATCH v4 09/12] KVM: x86/pmu: Forget PERFCTR_CORE if the min " Sean Christopherson
2023-02-14 5:07 ` [PATCH v4 10/12] KVM: x86/cpuid: Add X86_FEATURE_PERFMON_V2 as a scattered flag Like Xu
2023-04-07 0:41 ` Sean Christopherson
2023-02-14 5:07 ` [PATCH v4 11/12] KVM: x86/svm/pmu: Add AMD PerfMonV2 support Like Xu
2023-04-07 1:35 ` Sean Christopherson
2023-04-07 7:08 ` Like Xu
2023-04-07 14:44 ` Sean Christopherson
2023-04-10 11:34 ` Like Xu
2023-02-14 5:07 ` [PATCH v4 12/12] KVM: x86/cpuid: Add AMD CPUID ExtPerfMonAndDbg leaf 0x80000022 Like Xu
2023-04-07 1:50 ` Sean Christopherson
2023-04-07 7:19 ` Like Xu
2023-04-07 2:02 ` [PATCH v4 00/12] KVM: x86: Add AMD Guest PerfMonV2 PMU support Sean Christopherson
2023-04-07 7:28 ` Like Xu
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=20230214050757.9623-10-likexu@tencent.com \
--to=like.xu.linux@gmail.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=seanjc@google.com \
/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;
as well as URLs for NNTP newsgroup(s).