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Commit bfdb06df authored by Like Xu's avatar Like Xu Committed by Greg Kroah-Hartman
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perf/x86/amd: Don't touch the AMD64_EVENTSEL_HOSTONLY bit inside the guest

commit df51fe7e 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: 1018faa6

 ("perf/x86/kvm: Fix Host-Only/Guest-Only counting with SVM disabled")
Signed-off-by: default avatarLike Xu <likexu@tencent.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarLiam Merwick <liam.merwick@oracle.com>
Tested-by: default avatarKim Phillips <kim.phillips@amd.com>
Tested-by: default avatarLiam Merwick <liam.merwick@oracle.com>
Link: https://lkml.kernel.org/r/20210802070850.35295-1-likexu@tencent.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 1de1a42a
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