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Date:   Mon, 11 Oct 2021 14:07:15 +0100
From:   Lee Jones <lee.jones@linaro.org>
To:     Andi Kleen <ak@linux.intel.com>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        syzbot <syzbot+84fe685c02cd112a2ac3@syzkaller.appspotmail.com>,
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        linux-kernel@vger.kernel.org, mingo@redhat.com,
        syzkaller-bugs@googlegroups.com, tglx@linutronix.de,
        x86@kernel.org, Andy Lutomirski <luto@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>, tkjos@google.com
Subject: Re: [syzbot] KASAN: stack-out-of-bounds Read in profile_pc
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On Thu, 03 Jun 2021, Andi Kleen wrote:

> 
> > True, ftrace does have function profiling (function_profile_enabled).
> > 
> > Steve, is there a way to enable that on the kernel cmdline?
> 
> That's not really comparable. function profiling has a lot more overhead.
> Also there is various code which has ftrace instrumentation disabled.
> 
> I don't think why you want to kill the old profiler. It's rarely used, but
> when you need it usually works. It's always good to have simple fall backs.
> And it's not that it's a lot of difficult code.

sysbot is still sending out reports on this:

  https://syzkaller.appspot.com/bug?id=00c965d957410afc0d40cac5343064e0a98b9ecd

Are you guys still planning on sending out a fix?

Is there anything I can do to help?

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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