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Date: Wed, 22 Mar 2023 16:12:36 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Cc: <linux-fsdevel@vger.kernel.org>, <nvdimm@lists.linux.dev>,
 <dan.j.williams@intel.com>, <willy@infradead.org>, <jack@suse.cz>
Subject: Re: [PATCH] fsdax: dedupe should compare the min of two iters'
 length
Message-Id: <20230322161236.f90c21c8f668f551ee19d80b@linux-foundation.org>
In-Reply-To: <1679469958-2-1-git-send-email-ruansy.fnst@fujitsu.com>
References: <1679469958-2-1-git-send-email-ruansy.fnst@fujitsu.com>
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On Wed, 22 Mar 2023 07:25:58 +0000 Shiyang Ruan <ruansy.fnst@fujitsu.com> wrote:

> In an dedupe corporation iter loop, the length of iomap_iter decreases
> because it implies the remaining length after each iteration.  The
> compare function should use the min length of the current iters, not the
> total length.

Please describe the user-visible runtime effects of this flaw, thanks.