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    SubjectRe: [PATCH] perf,x86: fix kernel crash with PEBS/BTS after suspend/resume
    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


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