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Date: Sat, 10 Jan 2026 05:56:36 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Qu Wenruo <wqu@suse.com>
Cc: linux-btrfs@vger.kernel.org, linux-mm@kvack.org,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	Johannes Thumshirn <johannes.thumshirn@wdc.com>
Subject: Re: [PATCH v3 1/3] btrfs: use bdev_rw_virt() to read and scratch the
 disk super block
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References: <cover.1768017091.git.wqu@suse.com>
 <829db7e054cd290b5aed0b337cd219da128ac0e7.1768017091.git.wqu@suse.com>
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On Sat, Jan 10, 2026 at 02:26:19PM +1030, Qu Wenruo wrote:
> Furthermore read_cache_page*() can race with device block size setting,
> thus requires extra locking.

What?  There's supposed to be sufficient locking to prevent this.
Is there a bug report I can look at?