diff options
| author | Borislav Petkov <bp@suse.de> | 2019-05-08 19:02:48 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-05-24 21:27:13 +0200 |
| commit | a80c4ec10ed9632c44c829452dc40a0443ff4e85 (patch) | |
| tree | 352205c09ecfb0a07d31e0d464042df3aaaebfd5 | |
| parent | 6f2f84532c153d32a5e53b6083b06a3e24368d30 (diff) | |
x86/kvm/pmu: Set AMD's virt PMU version to 1
After commit:
672ff6cff80c ("KVM: x86: Raise #GP when guest vCPU do not support PMU")
my AMD guests started #GPing like this:
general protection fault: 0000 [#1] PREEMPT SMP
CPU: 1 PID: 4355 Comm: bash Not tainted 5.1.0-rc6+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:x86_perf_event_update+0x3b/0xa0
with Code: pointing to RDPMC. It is RDPMC because the guest has the
hardware watchdog CONFIG_HARDLOCKUP_DETECTOR_PERF enabled which uses
perf. Instrumenting kvm_pmu_rdpmc() some, showed that it fails due to:
if (!pmu->version)
return 1;
which the above commit added. Since AMD's PMU leaves the version at 0,
that causes the #GP injection into the guest.
Set pmu->version arbitrarily to 1 and move it above the non-applicable
struct kvm_pmu members.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: kvm@vger.kernel.org
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Mihai Carabas <mihai.carabas@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: stable@vger.kernel.org
Fixes: 672ff6cff80c ("KVM: x86: Raise #GP when guest vCPU do not support PMU")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/pmu_amd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kvm/pmu_amd.c b/arch/x86/kvm/pmu_amd.c index 1495a735b38e..50fa9450fcf1 100644 --- a/arch/x86/kvm/pmu_amd.c +++ b/arch/x86/kvm/pmu_amd.c @@ -269,10 +269,10 @@ static void amd_pmu_refresh(struct kvm_vcpu *vcpu) pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1; pmu->reserved_bits = 0xffffffff00200000ull; + pmu->version = 1; /* not applicable to AMD; but clean them to prevent any fall out */ pmu->counter_bitmask[KVM_PMC_FIXED] = 0; pmu->nr_arch_fixed_counters = 0; - pmu->version = 0; pmu->global_status = 0; } |