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Date: Thu, 5 Jun 2025 14:51:52 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Jan Kara <jack@suse.cz>
Cc: Chi Zhiling <chizhiling@163.com>, willy@infradead.org,
 josef@toxicpanda.com, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org, Chi Zhiling <chizhiling@kylinos.cn>
Subject: Re: [PATCH] readahead: fix return value of page_cache_next_miss()
 when no hole is found
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References: <20250605054935.2323451-1-chizhiling@163.com>
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On Thu, 5 Jun 2025 10:22:23 +0200 Jan Kara <jack@suse.cz> wrote:

> On Thu 05-06-25 13:49:35, Chi Zhiling wrote:
> > From: Chi Zhiling <chizhiling@kylinos.cn>
> > 
> > max_scan in page_cache_next_miss always decreases to zero when no hole
> > is found, causing the return value to be index + 0.
> > 
> > Fix this by preserving the max_scan value throughout the loop.
> > 
> > Fixes: 901a269ff3d5 ("filemap: fix page_cache_next_miss() when no hole found")
> > Signed-off-by: Chi Zhiling <chizhiling@kylinos.cn>
> 
> Indeed. Thanks for catching this. Don't know how I missed that. Feel free
> to add:
> 
> Reviewed-by: Jan Kara <jack@suse.cz>
> 

Thanks.  It's a simple patch - do we expect it to have significant
runtime effects?