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Date: Fri, 16 Jan 2026 14:34:32 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Francois Dugast <francois.dugast@intel.com>
Cc: intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Matthew
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Subject: Re: [PATCH v6 1/5] mm/zone_device: Reinitialize large zone device
 private folios
Message-Id: <20260116143432.50b98d6dc965b94f3b915333@linux-foundation.org>
In-Reply-To: <20260116111325.1736137-2-francois.dugast@intel.com>
References: <20260116111325.1736137-1-francois.dugast@intel.com>
	<20260116111325.1736137-2-francois.dugast@intel.com>
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On Fri, 16 Jan 2026 12:10:16 +0100 Francois Dugast <francois.dugast@intel.com> wrote:

> Reinitialize metadata for large zone device private folios in
> zone_device_page_init prior to creating a higher-order zone device
> private folio. This step is necessary when the folio’s order changes
> dynamically between zone_device_page_init calls to avoid building a
> corrupt folio. As part of the metadata reinitialization, the dev_pagemap
> must be passed in from the caller because the pgmap stored in the folio
> page may have been overwritten with a compound head.
> 
> Without this fix, individual pages could have invalid pgmap fields and
> flags (with PG_locked being notably problematic) due to prior different
> order allocations, which can, and will, result in kernel crashes.

Is it OK to leave 6.18.x without this fixed?