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Date: Thu, 19 Jun 2025 10:48:13 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
	bpf@vger.kernel.org, x86@kernel.org,
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	Jens Remus <jremus@linux.ibm.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v10 07/14] unwind_user/deferred: Make unwind deferral
 requests NMI-safe
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On Thu, Jun 19, 2025 at 10:44:27AM +0200, Peter Zijlstra wrote:

> Luckily, x86 dropped support for !CMPXCHG8B right along with !TSC. So on
> x86 we good with timestamps, even on 32bit.

Well, not entirely true, local_clock() is not guaranteed monotonic. So
you might be in for quite a bit of hurt if you rely on that.