Re: [RFC v2] perf: Rewrite core context handling

Ravi Bangoria
2022-08-29T03:55:18Z

On 23-Aug-22 9:50 AM, Ravi Bangoria wrote:
>
>> With this, I can run 'perf test' and perf_event_tests without any error in
>> dmesg. I'll run perf fuzzer over night and see if it reports any issue.
>
> I hit kernel crash with fuzzer. I'm yet to debug it. Here is the trace:
>
> BUG: kernel NULL pointer dereference, address: 0000000000000198
> #PF: supervisor read access in kernel mode
> #PF: error_code(0x0000) - not-present page
> PGD 0 P4D 0
> Oops: 0000 [#1] PREEMPT SMP NOPTI
> CPU: 48 PID: 0 Comm: swapper/48 Not tainted 6.0.0-rc1-perf-event-context-peter-queue+ #153
> Hardware name: Dell Inc. PowerEdge R6515/07PXPY, BIOS 2.7.3 03/31/2022
> RIP: 0010:x86_pmu_enable_event+0x3c/0x120

I was able to reproduce this with vanilla v6.0-rc2 kernel.

Thanks,
Ravi