Lendacky, Thomas 3966c3feca x86/perf/amd: Remove need to check "running" bit in NMI handler ... Spurious interrupt support was added to perf in the following commit, almost a decade ago: 63e6be6d98 ("perf, x86: Catch spurious interrupts after disabling counters") The two previous patches (resolving the race condition when disabling a PMC and NMI latency mitigation) allow for the removal of this older spurious interrupt support. Currently in x86_pmu_stop(), the bit for the PMC in the active_mask bitmap is cleared before disabling the PMC, which sets up a race condition. This race condition was mitigated by introducing the running bitmap. That race condition can be eliminated by first disabling the PMC, waiting for PMC reset on overflow and then clearing the bit for the PMC in the active_mask bitmap. The NMI handler will not re-enable a disabled counter. If x86_pmu_stop() is called from the perf NMI handler, the NMI latency mitigation support will guard against any unhandled NMI messages. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>		2019-04-10 13:03:18 +02:00
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boot	x86/boot: Fix incorrect ifdeffery scope	2019-03-27 14:00:51 +01:00
configs	Merge branch 'akpm' (patches from Andrew)	2019-03-07 19:25:37 -08:00
crypto
entry	pidfd patches for v5.1-rc1	2019-03-16 13:47:14 -07:00
events	x86/perf/amd: Remove need to check "running" bit in NMI handler	2019-04-10 13:03:18 +02:00
hyperv	x86/hyperv: Prevent potential NULL pointer dereference	2019-03-21 12:24:39 +01:00
ia32
include	A collection of x86 and ARM bugfixes, and some improvements to documentation.	2019-03-31 08:55:59 -07:00
kernel	x86/resctrl: Remove unused variable	2019-03-24 22:09:27 +01:00
kvm	KVM: x86: update %rip after emulating IO	2019-03-28 17:29:04 +01:00
lib	x86/lib: Fix indentation issue, remove extra tab	2019-03-21 12:24:38 +01:00
math-emu
mm	x86/mm: Don't exceed the valid physical address space	2019-03-28 14:13:51 +01:00
net
oprofile
pci
platform	x86/realmode: Make set_real_mode_mem() static inline	2019-03-29 10:16:27 +01:00
power
purgatory
ras
realmode	x86/realmode: Make set_real_mode_mem() static inline	2019-03-29 10:16:27 +01:00
tools
um
video
xen	Merge branch 'akpm' (patches from Andrew)	2019-03-12 10:39:53 -07:00
.gitignore
Kbuild
Kconfig	x86/smp: Enforce CONFIG_HOTPLUG_CPU when SMP=y	2019-03-28 13:34:58 +01:00
Kconfig.cpu
Kconfig.debug
Makefile	x86/retpolines: Disable switch jump tables when retpolines are enabled	2019-03-28 13:39:48 +01:00
Makefile_32.cpu
Makefile.um