Re: [syzbot] [block?] WARNING in blkdev_put (2)

[Julian Ruess <julianr@linux.ibm.com>]

On Thu, 2023-03-02 at 20:33 +0100, Alexander Egorenkov wrote:
> 
> Hi,
> 
> we are seeing a similar problem on s390x architecture when
> partitioning
> a NVMe disk on linux-next.
> 
> 
>   [   70.403015]  nvme0n1: p1
>   [   70.403197] ------------[ cut here ]------------
>   [   70.403199] WARNING: CPU: 8 PID: 2452 at block/bdev.c:845
> blkdev_put+0x280/0x298

...

> The problem appeared about a week ago.
> 
> Regards
> Alex

Hi all,

I bisected this to:

commit e5cfefa97bccf956ea0bb6464c1f6c84fd7a8d9f                       
Author: Yu Kuai <yukuai3@huawei.com>                                  
Date:   Fri Feb 17 10:22:00 2023 +0800                                
                                                                                      
    block: fix scan partition for exclusively open device again       
                                                                                      
    As explained in commit 36369f46e917 ("block: Do not reread
partition table        
    on exclusively open device"), reread partition on the device that
is              
    exclusively opened by someone else is problematic.                
                                                                                      
    This patch will make sure partition scan will only be proceed if
current          
    thread open the device exclusively, or the device is not opened   
    exclusively, and in the later case, other scanners and exclusive
openers          
    will be blocked temporarily until partition scan is done.         
                                                                                      
    Fixes: 10c70d95c0f2 ("block: remove the bd_openers checks in
blk_drop_partitions")
    Cc: <stable@vger.kernel.org>                                      
    Suggested-by: Jan Kara <jack@suse.cz>                             
    Signed-off-by: Yu Kuai <yukuai3@huawei.com>                       
    Reviewed-by: Christoph Hellwig <hch@lst.de>                       
    Link:
https://lore.kernel.org/r/20230217022200.3092987-3-yukuai1@huaweicloud.com
 
    Signed-off-by: Jens Axboe <axboe@kernel.dk>   



Regards
Julian

-- 
Julian Ruess
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