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	Mon, 23 Mar 2026 06:17:58 +0000
Date: Sun, 22 Mar 2026 23:17:58 -0700
From: Christoph Hellwig <hch@infradead.org>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Zorro Lang <zlang@redhat.com>, linux-xfs@vger.kernel.org,
	Tal Zussman <tz2294@columbia.edu>, axboe@kernel.dk,
	linux-block@vger.kernel.org
Subject: Re: [Bug][xfstests xfs/556] inconsistent {HARDIRQ-ON-W} ->
 {IN-HARDIRQ-W} usage
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References: <20260319194303.efw4wcu7c4idhthz@doltdoltdolt>
 <20260320163444.GE6223@frogsfrogsfrogs>
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On Fri, Mar 20, 2026 at 09:34:44AM -0700, Darrick J. Wong wrote:
> --- a/fs/iomap/bio.c
> +++ b/fs/iomap/bio.c
> @@ -8,7 +8,15 @@
>  #include "internal.h"
>  #include "trace.h"
>  
> -static void iomap_read_end_io(struct bio *bio)
> +struct iomap_failed_bio {
> +	struct list_head io_list;
> +	struct bio *bio;
> +};

Between this and the blockdev dontcache work I really wish we could
have a generic offload using a percpu lit and workqueue.

Also I don't think we need the separate list here, a linked list using
bi_next should be sufficient and avoid the allocation in the failure
path.