Re: [PATCH blktests] tests/md: add test 005 for raid1 deadlock under I/O, limit changes and recovery

[Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>]

On Sep 10, 2026 / 12:09, Jack Wang wrote:
> From: Jack Wang <jinpu.wang@cloud.ionos.com>
> 
> Add a regression test for a deadlock reported against raid1 with an
> internal bitmap, where concurrent I/O, queue limit updates
> (max_sectors_kb) and device fail/remove/add (recovery) cycles can
> deadlock.
> 
> The test creates a raid1 array with an internal bitmap on two brd
> devices, drives it with fio while repeatedly toggling
> max_sectors_kb and cycling one member through fail/remove/add, and
> flags a likely deadlock if any of these steps fail to make progress
> within a bounded timeout.
> 
> Link: https://lore.kernel.org/linux-raid/CAMGffE=heGA3y8FjQ0Sm1jj-kd-=H9Y54WozKASSEZhc9UNKjA@mail.gmail.com/T/#t
> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>

Thanks for the patch. Overall, the patch looks good to me. I have one comment in
line. Also, I ran the test case on v7.3-rc4 kernel, and confirmed it avois the
hang. When I applied the kernel side fix v2 series [*] on top of v7.3-rc4
kernel, and confirmed that the test case passes. Good.

[*] https://lore.kernel.org/linux-block/20260910081114.1605746-1-jinpu.wang@ionos.com/

I will wait for the kernel side patches get settled on Linus master branch
before applying this patch. Thanks!


[...]

> diff --git a/tests/md/005 b/tests/md/005
> new file mode 100755
> index 000000000000..5493d0edc933
> --- /dev/null
> +++ b/tests/md/005
> @@ -0,0 +1,142 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-3.0+
> +# Copyright (C) 2026 Jack Wang
> +#
> +# Regression test for a deadlock reported against raid1 with an internal
> +# bitmap, where concurrent I/O, queue limit updates (max_sectors_kb) and
> +# device fail/remove/add cycles (recovery) can deadlock.
> +#
> +# See: https://lore.kernel.org/linux-raid/CAMGffE=heGA3y8FjQ0Sm1jj-kd-=H9Y54WozKASSEZhc9UNKjA@mail.gmail.com/T/#t
> +
> +. tests/md/rc
> +. common/brd
> +. common/fio
> +
> +DESCRIPTION="test for raid1 deadlock with internal bitmap under I/O, queue limit changes and fail/remove/add"

This description line looks a bit lengthy. How about to make it shorter as
follows?

"raid1 internal bitmap race among I/O, queue limit changes and fail/remove/add"

If you are okay with it, I can fold in the change when I apply the patch.