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authorLike Xu <likexu@tencent.com>2021-08-02 15:08:50 +0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-08-15 13:03:32 +0200
commit254f73e235eec6d278fec6eb463225bbfc75b617 (patch)
tree5c12140ced055828582f1b418ddfcbf6bd9fff79 /arch/x86
parentff056817560d72363b463ddac27822dc8c121280 (diff)
perf/x86/amd: Don't touch the AMD64_EVENTSEL_HOSTONLY bit inside the guest
commit df51fe7ea1c1c2c3bfdb81279712fdd2e4ea6c27 upstream. If we use "perf record" in an AMD Milan guest, dmesg reports a #GP warning from an unchecked MSR access error on MSR_F15H_PERF_CTLx: [] unchecked MSR access error: WRMSR to 0xc0010200 (tried to write 0x0000020000110076) at rIP: 0xffffffff8106ddb4 (native_write_msr+0x4/0x20) [] Call Trace: [] amd_pmu_disable_event+0x22/0x90 [] x86_pmu_stop+0x4c/0xa0 [] x86_pmu_del+0x3a/0x140 The AMD64_EVENTSEL_HOSTONLY bit is defined and used on the host, while the guest perf driver should avoid such use. Fixes: 1018faa6cf23 ("perf/x86/kvm: Fix Host-Only/Guest-Only counting with SVM disabled") Signed-off-by: Like Xu <likexu@tencent.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Tested-by: Kim Phillips <kim.phillips@amd.com> Tested-by: Liam Merwick <liam.merwick@oracle.com> Link: https://lkml.kernel.org/r/20210802070850.35295-1-likexu@tencent.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/events/perf_event.h3
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index bfe16631fd1d..ccd14aca30e7 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -792,9 +792,10 @@ void x86_pmu_stop(struct perf_event *event, int flags);
static inline void x86_pmu_disable_event(struct perf_event *event)
{
+ u64 disable_mask = __this_cpu_read(cpu_hw_events.perf_ctr_virt_mask);
struct hw_perf_event *hwc = &event->hw;
- wrmsrl(hwc->config_base, hwc->config);
+ wrmsrl(hwc->config_base, hwc->config & ~disable_mask);
}
void x86_pmu_enable_event(struct perf_event *event);