Messages in this thread | | | Date | Fri, 15 Mar 2013 14:53:35 -0600 | Subject | Re: [PATCH] perf,x86: fix kernel crash with PEBS/BTS after suspend/resume | From | Shuah Khan <> |
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On Fri, Mar 15, 2013 at 2:31 PM, Greg KH <gregkh@linuxfoundation.org> wrote: > On Fri, Mar 15, 2013 at 02:26:07PM +0100, Stephane Eranian wrote: >> >> This patch fixes a kernel crash when using precise sampling (PEBS) >> after a suspend/resume. Turns out the CPU notifier code is not invoked >> on CPU0 (BP). Therefore, the DS_AREA (used by PEBS) is not restored properly >> by the kernel and keeps it power-on/resume value of 0 causing any PEBS >> measurement to crash when running on CPU0. >> >> The workaround is to add a hook in the actual resume code to restore >> the DS Area MSR value. It is invoked for all CPUS. So for all but CPU0, >> the DS_AREA will be restored twice but this is harmless. >> >> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> >> Signed-off-by: Stephane Eranian <eranian@google.com> >> --- > > Is this needed for the 3.8 or older kernels as well? > > thanks, > > greg k-h
Just about to ask the same question. Patch applies to 3.8, 3.4, 3.2 and 3.5. But needs some massaging for 3.0. I have the kernels built, haven't started testing yet.
-- Shuah
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