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Date:   Fri, 22 Jul 2022 20:17:25 +0530
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To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Jiri Olsa <olsajiri@gmail.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
From:   Ravi Bangoria <ravi.bangoria@amd.com>
Subject: Question on perf event context swap at process switch
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Hi Peter,

Consider two processes having clone contexts (for example, two children of
the same parent). While process switch between these two, the perf event
context would get swapped but event->hw.target will point to other sibling's
task_struct. If that process exit just after one context swap, _free_event()
will call put_task_context() on sibling process' task_struct. Wouldn't it
result into fatal error later?

Thanks,
Ravi