Re: [PATCH] writeback: don't warn on an unregistered BDI in __mark_inode_dirty

[Jan Kara <jack@suse.cz>]

On Mon 28-09-20 14:26:13, Christoph Hellwig wrote:
> BDIs get unregistered during device removal, and this WARN can be
> trivially triggered by hot-removing a NVMe device while running fsx
> It is otherwise harmless as we still hold a BDI reference, and the
> writeback has been shut down already.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> 
> I have a vague memory someone else sent this patch alredy, but couldn't
> find it in my mailing list folder.  But given that my current NVMe
> tests trigger it easily I'd rather get it fixed ASAP.

Did this patch get lost? I don't see it upstream or in Jens' tree. FWIW I
agree the warning may result in false positive so I'm OK with removing it.
So feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> 
>  fs/fs-writeback.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
> index e6005c78bfa93e..acfb55834af23c 100644
> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -2321,10 +2321,6 @@ void __mark_inode_dirty(struct inode *inode, int flags)
>  
>  			wb = locked_inode_to_wb_and_lock_list(inode);
>  
> -			WARN((wb->bdi->capabilities & BDI_CAP_WRITEBACK) &&
> -			     !test_bit(WB_registered, &wb->state),
> -			     "bdi-%s not registered\n", bdi_dev_name(wb->bdi));
> -
>  			inode->dirtied_when = jiffies;
>  			if (dirtytime)
>  				inode->dirtied_time_when = jiffies;
> -- 
> 2.28.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR