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Date:   Fri, 25 Nov 2022 08:41:19 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc:     x86@kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        linux-kernel@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
        Huacai Chen <chenhuacai@loongson.cn>,
        Jinyang He <hejinyang@loongson.cn>,
        Tiezhu Yang <yangtiezhu@loongson.cn>,
        "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>
Subject: Re: [PATCH -tip] x86/kprobes: Handle removed INT3 in do_int3()
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References: <166933854220.2683864.10006153553442313230.stgit@devnote3>
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On Fri, Nov 25, 2022 at 10:09:02AM +0900, Masami Hiramatsu (Google) wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> Since x86 doesn't use stop_machine() to patch the kernel text,
> there is a small chance that the another CPU removes the INT3
> during do_int3(). In this case, if no INT3 notifier callbacks
> handled that, the kernel calls die() because of a stray INT3.

Please clarify; how would that happen? Should not everybody modifying
text take text_mutex ?