Re: PROBLEM: repeatable lockup on RAID-6 with LUKS dm-crypt on NVMe devices when rsyncing many files

[Christian Theune <ct@flyingcircus.io>]

Hi

> On 5. Nov 2024, at 02:20, Yu Kuai <yukuai1@huaweicloud.com> wrote:
> 
> Thanks for the test, and sorry that I just realized my patch doesn't fix
> the problem I noticed. :(
> 
> Please test again with the following patch on the top. I'm confident
> that this is a real problem at least.
> 
> Thanks for the testing!
> Kuai
> 
> diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
> index 04f32173839a..7ec6a5d2d166 100644
> --- a/drivers/md/raid5.c
> +++ b/drivers/md/raid5.c
> @@ -4042,7 +4042,7 @@ static void handle_stripe_clean_event(struct r5conf *conf,
>                             test_bit(R5_SkipCopy, &dev->flags))) {
>                                /* We can return any write requests */
>                                struct bio *wbi, *wbi2;
> -                               bool written = false;
> +                               bool written;
> 
>                                pr_debug("Return write for disc %d\n", i);
>                                if (test_and_clear_bit(R5_Discard, &dev->flags))
> @@ -4053,6 +4053,7 @@ static void handle_stripe_clean_event(struct r5conf *conf,
>                                do_endio = true;
> 
> returnbi:
> +                               written = false;
>                                dev->page = dev->orig_page;
>                                wbi = dev->written;
>                                dev->written = NULL;

Heh - I stared at your first patch earlier and had somewhat of a hunch that the looping part would need a reset but I didn’t quite trust my intuition as I don’t know the code well enough … ;)

I’m booting with this additional change now and will report back again later.

Christian

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