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Date: Sun, 21 Jan 2024 10:33:23 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Matthieu Baerts <matttbe@kernel.org>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>, x86@kernel.org,
 Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
 Borislav Petkov <bp@alien8.de>, Peter Zijlstra <peterz@infradead.org>,
 linux-kernel@vger.kernel.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 v2] x86/kprobes: Drop removed INT3 handling code
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On Sun, 21 Jan 2024 10:31:44 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:

> My guess is that qemu does not treat the IPI being sent as a memory
> barrier, and then the CPUs do not see a consistent memory view after
> the IPIs are sent. That's a bug in qemu!

More specifically, I bet qemu may be doing a dcache barrier, but not an
icache barrier in the interrupt. If the code is already in qemu's
pipeline, it may not be flushing it like real hardware would do.

-- Steve