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From: Sasha Levin <sashal@kernel.org>
To: stable@vger.kernel.org
Cc: Sasha Levin <sashal@kernel.org>,
	Lu Baolu <baolu.lu@linux.intel.com>,
	Dmytro Maluka <dmaluka@chromium.org>,
	Samiullah Khawaja <skhawaja@google.com>,
	Kevin Tian <kevin.tian@intel.com>,
	Joerg Roedel <joerg.roedel@amd.com>,
	David Woodhouse <dwmw2@infradead.org>,
	Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	"Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Adrian Bunk <bunk@stusta.de>,
	iommu@lists.linux.dev,
	linux-kernel@vger.kernel.org,
	Konstantin Andreev <andreev@swemel.ru>
Subject: Re: [PATCH 6.12.y] iommu/vt-d: Clear Present bit before tearing down context entry
Date: Thu, 16 Jul 2026 21:37:32 -0400
Message-ID: <20260716232340.0005-stable-reply@kernel.org>
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On Wed, Jul 15, 2026 at 01:21:23AM +0300, Konstantin Andreev wrote:
> When tearing down a context entry, the current implementation zeros the
> entire 128-bit entry using multiple 64-bit writes. This creates a window
> where the hardware can fetch a "torn" entry — where some fields are
> already zeroed while the 'Present' bit is still set — leading to
> unpredictable behavior or spurious faults.

Queued for 6.12, thanks.

-- 
Thanks,
Sasha