Re: [PATCH 1/2] md/raid0: Free r0conf memory when register integrity failed

From: Xiao Ni <xni@redhat.com>
To: Guoqing Jiang <guoqing.jiang@linux.dev>
Cc: Song Liu <song@kernel.org>, Nigel Croxon <ncroxon@redhat.com>,
	linux-raid <linux-raid@vger.kernel.org>
Subject: Re: [PATCH 1/2] md/raid0: Free r0conf memory when register integrity failed
Date: Fri, 10 Dec 2021 09:34:20 +0800	[thread overview]
Message-ID: <CALTww293ewiXD8s0b-sLbdFZgnxMZh=5e4Fj=WMB+ifoJcNP7g@mail.gmail.com> (raw)
In-Reply-To: <978b1c0a-2ba0-d736-8e3c-99a15997b7d5@linux.dev>

On Fri, Dec 10, 2021 at 9:22 AM Guoqing Jiang <guoqing.jiang@linux.dev> wrote:
>
>
>
> On 12/10/21 2:02 AM, Song Liu wrote:
> > On Wed, Dec 8, 2021 at 9:55 PM Xiao Ni<xni@redhat.com>  wrote:
> >> It doesn't free memory when register integrity failed. And move
> >> free conf codes into a single function.
> >>
> >> Signed-off-by: Xiao Ni<xni@redhat.com>
> >> ---
> >>   drivers/md/raid0.c | 18 +++++++++++++++---
> >>   1 file changed, 15 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
> >> index 62c8b6adac70..3fa47df1c60e 100644
> >> --- a/drivers/md/raid0.c
> >> +++ b/drivers/md/raid0.c
> >> @@ -356,6 +356,7 @@ static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks
> >>          return array_sectors;
> >>   }
> >>
> >> +static void free_conf(struct r0conf *conf);
> >>   static void raid0_free(struct mddev *mddev, void *priv);
> >>
> >>   static int raid0_run(struct mddev *mddev)
> >> @@ -413,19 +414,30 @@ static int raid0_run(struct mddev *mddev)
> >>          dump_zones(mddev);
> >>
> >>          ret = md_integrity_register(mddev);
> >> +       if (ret)
> >> +               goto free;
> >>
> >>          return ret;
> >> +
> >> +free:
> >> +       free_conf(conf);
> > Can we just use raid0_free() here? Also, after freeing conf,
> > we should set mddev->private to NULL.
>
> Agree, like what raid1_run did. And we might need to check the
> return value of pers->run in level_store as well.

Yes. It needs to check the return value and try to reback to the original
state. I planed to fix this in the following days not this patch. This patch
only fix the NULL reference problem after reshape.

In fact, no only we need to check pers->run in level_store, we also need
to check integrity during reshape. Now integrity only supports
raid0/raid1/raid10,
so it needs to do some jobs related with integrity (unregister/register)

I plan to fix these two problems in the next patches. Is it OK?

Regards
Xiao