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Message-ID: <4753802a-685f-ab56-fed2-22d6eb4cfccd@squashfs.org.uk>
Date:   Thu, 30 Mar 2023 19:59:46 +0100
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Subject: Re: [PATCH 1/2] block: Rework bio_for_each_segment_all()
To:     Kent Overstreet <kent.overstreet@linux.dev>
Cc:     linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
        willy@infradead.org, axboe@kernel.dk,
        Ming Lei <ming.lei@redhat.com>
References: <20230327174402.1655365-1-kent.overstreet@linux.dev>
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 <52a5bd5c-d3a1-71d7-e1e5-7965501818bd@squashfs.org.uk>
 <ZCXNDQ6Eslhj+9g5@moria.home.lan>
From:   Phillip Lougher <phillip@squashfs.org.uk>
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On 30/03/2023 18:55, Kent Overstreet wrote:
> On Wed, Mar 29, 2023 at 05:50:27PM +0100, Phillip Lougher wrote:
>> There is a problem with the above code, on testing I get the following
>> results:
>>
>> Index 78018785329, offset 49, bvec.bv_len 1024: In same bio, metadata length
>> 32780
> 
> Could you share how you're doing your testing? I set up a basic test
> (created images using every compression type, tested reading them) and
> so far I'm not able to reproduce this.

I use a very large Squashfs file that triggers the edge case.

That is too big to post, and so I'll see if I can artifically generate
a small Squashfs filesystem that triggers the edge case.

Phillip