Re: [PATCH v2 1/4] perf/core: check return value of perf_event_read IPI

From	David Carrillo-Cisneros <davidcc@google.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2 1/4] perf/core: check return value of perf_event_read IPI
Date	2016-08-17 23:00 +0200
Message-ID	<s7g6l-6kR-11@gated-at.bofh.it> (permalink)
References	<s3mN3-6xA-1@gated-at.bofh.it> <s3mN4-6xA-13@gated-at.bofh.it> <s4I8O-1sK-11@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

> > The call to smp_call_function_single in perf_event_read() may fail and,
> > when it does, its error value is the one to return.
> >
> Please also describe the symptoms of the bug - under what circumstances may the
> smp-call fail and how does the user notice?
>
> Thanks,
>
>         Ingo
generic_exec_single only fails if cpu is invalid or not online, which
currently is not supposed to happen. Since perf_event_read's error is
not checked, I guess a WARN_ON_ONCE is needed. I'll post a rebased
version with this change.

Thanks,
David

Back to linux.kernel | Previous | Next | Find similar | Unroll thread

Thread

Re: [PATCH v2 1/4] perf/core: check return value of perf_event_read IPI David Carrillo-Cisneros <davidcc@google.com> - 2016-08-17 23:00 +0200

csiph-web