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Date: Mon, 2 Mar 2026 10:23:06 +0000
From: Mark Rutland <mark.rutland@arm.com>
To: Khaja Hussain Shaik Khaji <khaja.khaji@oss.qualcomm.com>
Cc: ada.coupriediaz@arm.com, catalin.marinas@arm.com, dev.jain@arm.com,
	linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org,
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	yang@os.amperecomputing.com
Subject: Re: [PATCH v2 1/2] arm64: kprobes: disable preemption across XOL
 single-step
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References: <aZSdkGjy2BXUL0bT@J2N7QTR9R3.cambridge.arm.com>
 <20260302101905.3591689-1-khaja.khaji@oss.qualcomm.com>
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In-Reply-To: <20260302101905.3591689-1-khaja.khaji@oss.qualcomm.com>

On Mon, Mar 02, 2026 at 03:49:05PM +0530, Khaja Hussain Shaik Khaji wrote:
> On Tue, Feb 17, 2026 at 04:55:44PM +0000, Mark Rutland wrote:
> > Since DAIF is masked, we won't take an IRQ to preempt during XOL.
> > Can you please share an example failure that you have seen?
> > I believe other architectures are likely affected by the same problem.
> 
> Thank you for the review. You were correct on all counts.
> 
> I confirmed the issue is not related to scheduling or preemption, and the
> v1/v2 approach was based on an incorrect assumption. I’m dropping that
> line of reasoning.
> 
> I’ve since identified the actual root cause and have a new fix ready,
> which I’ll send shortly as v3.

Ok.

As above, *please* include an observed failure in the commit message. It
will be the first thing we ask for otherwise.

Mark.