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Date:   Mon, 15 Aug 2022 22:16:29 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Johannes Erdfelt <johannes@erdfelt.com>,
        Ingo Molnar <mingo@redhat.com>, live-patching@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        "x86@kernel.org" <x86@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: ftrace regression with CONFIG_UNWINDER_FRAME_POINTER
Message-ID: <YvqpnfM9ZdRO6oXa@zn.tnic>
References: <20220815195828.GE3948@sventech.com>
 <20220815160646.0dca7227@gandalf.local.home>
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On Mon, Aug 15, 2022 at 04:06:46PM -0400, Steven Rostedt wrote:
> On Mon, 15 Aug 2022 12:58:28 -0700
> Johannes Erdfelt <johannes@erdfelt.com> wrote:
> 
> > I recently ran across an oops with ftrace when using the frame pointer
> > unwinder. It does not affect Linus' tree (tested 6.0-rc1), but it does
> > affect 5.15.60 and 5.10.136 (at least, have not tested other kernels).
> > 
> > It appears to be related to the recently merged retbleed mitigations,
> 
> If you believe this, then Cc those that are involved with those
> mitigations, which I did.

Sounds like this one:

https://lore.kernel.org/all/Yu2H%2FRdg%2FU4bHWaY@quatroqueijos/

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette