diff options
| author |   CodyYao-oc <CodyYao-oc@zhaoxin.com> | 2021-06-07 10:53:35 +0800 |
|---|---|---|
| committer |   Peter Zijlstra <peterz@infradead.org> | 2021-06-10 10:04:40 +0200 |
| commit | a8383dfb2138742a1bb77b481ada047aededa2ba (patch) | |
| tree | 2b05d96e731a709a051f92cbf2c3de834d5ff1e1 /arch/x86/kernel/cpu/perfctr-watchdog.c | |
| parent | irq_work: Make irq_work_queue() NMI-safe again (diff) | |
| download | linux-dev-a8383dfb2138742a1bb77b481ada047aededa2ba.tar.xz linux-dev-a8383dfb2138742a1bb77b481ada047aededa2ba.zip | |
x86/nmi_watchdog: Fix old-style NMI watchdog regression on old Intel CPUs
The following commit:
3a4ac121c2ca ("x86/perf: Add hardware performance events support for Zhaoxin CPU.")
Got the old-style NMI watchdog logic wrong and broke it for basically every
Intel CPU where it was active. Which is only truly old CPUs, so few people noticed.
On CPUs with perf events support we turn off the old-style NMI watchdog, so it
was pretty pointless to add the logic for X86_VENDOR_ZHAOXIN to begin with ... :-/
Anyway, the fix is to restore the old logic and add a 'break'.
[ mingo: Wrote a new changelog. ]
Fixes: 3a4ac121c2ca ("x86/perf: Add hardware performance events support for Zhaoxin CPU.")
Signed-off-by: CodyYao-oc <CodyYao-oc@zhaoxin.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210607025335.9643-1-CodyYao-oc@zhaoxin.com
Diffstat (limited to 'arch/x86/kernel/cpu/perfctr-watchdog.c')
| -rw-r--r-- | arch/x86/kernel/cpu/perfctr-watchdog.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c index 3ef5868ac588..7aecb2fc3186 100644 --- a/arch/x86/kernel/cpu/perfctr-watchdog.c +++ b/arch/x86/kernel/cpu/perfctr-watchdog.c @@ -63,7 +63,7 @@ static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr) case 15: return msr - MSR_P4_BPU_PERFCTR0; } - fallthrough; + break; case X86_VENDOR_ZHAOXIN: case X86_VENDOR_CENTAUR: return msr - MSR_ARCH_PERFMON_PERFCTR0; @@ -96,7 +96,7 @@ static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr) case 15: return msr - MSR_P4_BSU_ESCR0; } - fallthrough; + break; case X86_VENDOR_ZHAOXIN: case X86_VENDOR_CENTAUR: return msr - MSR_ARCH_PERFMON_EVENTSEL0; |