[tip:perf/urgent] perf/x86: Apply more accurate check on hypervisor platform
From: tip-bot for Zhenzhong Duan
Date: Thu Jul 25 2019 - 14:08:04 EST
Commit-ID: 5ea3f6fb37b79da33ac9211df336fd2b9f47c39f
Gitweb: https://git.kernel.org/tip/5ea3f6fb37b79da33ac9211df336fd2b9f47c39f
Author: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxxx>
AuthorDate: Thu, 25 Jul 2019 10:39:26 +0800
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 25 Jul 2019 15:41:30 +0200
perf/x86: Apply more accurate check on hypervisor platform
check_msr is used to fix a bug report in guest where KVM doesn't support
LBR MSR and cause #GP.
The msr check is bypassed on real HW to workaround a false failure,
see commit d0e1a507bdc7 ("perf/x86/intel: Disable check_msr for real HW")
When running a guest with CONFIG_HYPERVISOR_GUEST not set or "nopv"
enabled, current check isn't enough and #GP could trigger.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/1564022366-18293-1-git-send-email-zhenzhong.duan@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/events/intel/core.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index b35519cbc8b4..c9075fc75cb6 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -20,7 +20,6 @@
#include <asm/intel-family.h>
#include <asm/apic.h>
#include <asm/cpu_device_id.h>
-#include <asm/hypervisor.h>
#include "../perf_event.h"
@@ -4053,7 +4052,7 @@ static bool check_msr(unsigned long msr, u64 mask)
* Disable the check for real HW, so we don't
* mess with potentionaly enabled registers:
*/
- if (hypervisor_is_type(X86_HYPER_NATIVE))
+ if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
return true;
/*