On Thu, 2017-11-30 at 08:33:22 UTC, Ravi Bangoria wrote:
> When user tries to group imc (In-Memory Collections) event with
> normal event, (sometime) kernel crashes with following log:
>
> Faulting instruction address: 0x00000000
> [link register ] c00000000010ce88 power_check_constraints+0x128/0x980
> ...
> c00000000010e238 power_pmu_event_init+0x268/0x6f0
> c0000000002dc60c perf_try_init_event+0xdc/0x1a0
> c0000000002dce88 perf_event_alloc+0x7b8/0xac0
> c0000000002e92e0 SyS_perf_event_open+0x530/0xda0
> c00000000000b004 system_call+0x38/0xe0
>
> 'event_base' field of 'struct hw_perf_event' is used as flags for
> normal hw events and used as memory address for imc events. While
> grouping these two types of events, collect_events() tries to
> interpret imc 'event_base' as a flag, which causes a corruption
> resulting in a crash.
>
> Consider only those events which belongs to 'perf_hw_context' in
> collect_events().
>
> Signed-off-by: Ravi Bangoria <[email protected]>
> Reviewed-By: Madhavan Srinivasan <[email protected]>
Applied to powerpc fixes, thanks.
https://git.kernel.org/powerpc/c/5aa04b3eb6fca63d2e9827be656dca
cheers