A regression is seen where mddev devices stay permanently after they
are stopped due to an elevated reference count.
This was tracked down to an extra mddev_get() in md_seq_start().
It only happened rarely because most of the time the md_seq_start()
is called with a zero offset. The path with an extra mddev_get() only
happens when it starts with a non-zero offset.
The commit noted below changed an mddev_get() to check its success
but inadevrtantly left the original call in. Remove the extra call.
Fixes: 12a6caf27324 ("md: only delete entries from all_mddevs when the disk is freed")
Signed-off-by: Logan Gunthorpe <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Acked-by: Guoqing Jiang <[email protected]>
---
drivers/md/md.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index afaf36b2f6ab..9dc0175280b4 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8154,7 +8154,6 @@ static void *md_seq_start(struct seq_file *seq, loff_t *pos)
list_for_each(tmp,&all_mddevs)
if (!l--) {
mddev = list_entry(tmp, struct mddev, all_mddevs);
- mddev_get(mddev);
if (!mddev_get(mddev))
continue;
spin_unlock(&all_mddevs_lock);
--
2.30.2
Dear Logan,
Thank you for the updated series. One nit below, which could be
corrected by the maintainer before applying.
Am 08.09.22 um 18:15 schrieb Logan Gunthorpe:
> A regression is seen where mddev devices stay permanently after they
> are stopped due to an elevated reference count.
>
> This was tracked down to an extra mddev_get() in md_seq_start().
>
> It only happened rarely because most of the time the md_seq_start()
> is called with a zero offset. The path with an extra mddev_get() only
> happens when it starts with a non-zero offset.
>
> The commit noted below changed an mddev_get() to check its success
> but inadevrtantly left the original call in. Remove the extra call.
inadvertently
> Fixes: 12a6caf27324 ("md: only delete entries from all_mddevs when the disk is freed")
> Signed-off-by: Logan Gunthorpe <[email protected]>
> Reviewed-by: Christoph Hellwig <[email protected]>
> Acked-by: Guoqing Jiang <[email protected]>
> ---
> drivers/md/md.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index afaf36b2f6ab..9dc0175280b4 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -8154,7 +8154,6 @@ static void *md_seq_start(struct seq_file *seq, loff_t *pos)
> list_for_each(tmp,&all_mddevs)
> if (!l--) {
> mddev = list_entry(tmp, struct mddev, all_mddevs);
> - mddev_get(mddev);
> if (!mddev_get(mddev))
> continue;
> spin_unlock(&all_mddevs_lock);
Kind regards,
Paul