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Date:   Fri, 31 Mar 2023 22:28:58 -0400
From:   Kent Overstreet <kent.overstreet@linux.dev>
To:     Phillip Lougher <phillip@squashfs.org.uk>
Cc:     linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
        willy@infradead.org, axboe@kernel.dk,
        Ming Lei <ming.lei@redhat.com>
Subject: Re: [PATCH 1/2] block: Rework bio_for_each_segment_all()
Message-ID: <ZCeW6j44aHGI/v5Q@moria.home.lan>
References: <20230327174402.1655365-1-kent.overstreet@linux.dev>
 <20230327174402.1655365-2-kent.overstreet@linux.dev>
 <52a5bd5c-d3a1-71d7-e1e5-7965501818bd@squashfs.org.uk>
 <ZCXNDQ6Eslhj+9g5@moria.home.lan>
 <4753802a-685f-ab56-fed2-22d6eb4cfccd@squashfs.org.uk>
 <5ab59623-4317-5aff-5173-d7285b5b224c@squashfs.org.uk>
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On Fri, Mar 31, 2023 at 02:10:15AM +0100, Phillip Lougher wrote:
> On 30/03/2023 19:59, Phillip Lougher wrote:
> > 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
> > 
> > 
> 
> Hi,
> 
> This is a Google drive link to a file that triggers the issue.
> 
> https://drive.google.com/file/d/1-3-a1BKq62hZGQ6ynioreMSWFMuCV9B4/view?usp=sharing
> 
> To reproduce the issue
> 
> % mount -t squashfs <the file> /mnt -o errors=panic
> 
> then either one of the following will produce a panic
> 
> % ls /mnt
> % find /mnt -type f | xargs wc > /dev/null

Appears to be fixed now - updated version of the patchset is at
https://evilpiepirate.org/git/bcachefs.git bio_folio_iter

Can you confirm, then I'll mail out the updated series?