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Date: Sun, 16 Oct 2016 09:01:30 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>,
        Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
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        Masami Hiramatsu <mhiramat@kernel.org>,
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Subject: Re: [PATCH v5] kprobes: unpoison stack in jprobe_return() for KASAN
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* Dmitry Vyukov <dvyukov@google.com> wrote:

> On Sat, Oct 15, 2016 at 8:30 AM, Ingo Molnar <mingo@kernel.org> wrote:
> >
> > * Dmitry Vyukov <dvyukov@google.com> wrote:
> >
> >> KASAN stack instrumentation poisons stack redzones on function entry
> >> and unpoisons them on function exit. If a function exits abnormally
> >> (e.g. with a longjmp like jprobe_return()), stack redzones are left
> >> poisoned. Later this leads to random KASAN false reports.
> >>
> >> Unpoison stack redzones in the frames we are going to jump over
> >> before doing actual longjmp in jprobe_return().
> >
> > Does this affect any other architecture besides arm64? If not then it might make
> > the most sense to merge this via the arm64 tree.
> 
> 
> This is mostly for x86_64. This patch fixes KASAN false positives
> related to jprobe on x86_64.

Indeed: I should have read the patch beyond the diffstat.

> Arm64 related part is only a function rename. As I introduce a
> function similar to an existing one, Mark asked to me rename the
> existing function to clarify the difference between the two.

Fair enough!

Thanks,

	Ingo