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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Waiman Long <longman@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
	Clark Williams <clrkwllms@kernel.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-rt-devel@lists.linux.dev
Subject: Re: [PATCH] arm64/entry: Don't disable preemption in
 debug_exception_enter() with RT kernel
Message-ID: <20260520061920.XCqBHe0x@linutronix.de>
References: <20260519222524.886454-1-longman@redhat.com>
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In-Reply-To: <20260519222524.886454-1-longman@redhat.com>

On 2026-05-19 18:25:24 [-0400], Waiman Long wrote:
> Commit d8bb6718c4db ("arm64: Make debug exception handlers visible from
> RCU") introduces debug_exception_enter() and debug_exception_exit()
> where preemption is explicitly disabled. With a PREEMPT_RT debug kernel,
> the following bug report can happen.
=E2=80=A6

What kernel is this? I have backport (which is being tested) for v6.6
and v6.12, the patches are from v6.17-rc1.

Sebastian