Re: [PATCH RFC 2/3] btrfs: consolidate device_list_mutex in prepare_sprout to its parent

[Anand Jain <anand.jain@oracle.com>]

On 23/08/2021 18:34, Anand Jain wrote:
> On 21/08/2021 23:00, Su Yue wrote:
>>
>> On Sat 21 Aug 2021 at 22:57, Su Yue <l@damenly.su> wrote:
>>
>>> On Fri 20 Aug 2021 at 16:53, Anand Jain <anand.jain@oracle.com>
>>> wrote:
>>>
>>>>>> @@ -2366,6 +2366,8 @@ static int btrfs_prepare_sprout(struct
>>>>>> btrfs_fs_info *fs_info)
>>>>>>      u64 super_flags;
>>>>>>
>>>>>>      lockdep_assert_held(&uuid_mutex);
>>>>>> +    lockdep_assert_held(&fs_devices->device_list_mutex);
>>>>>> +
>>>>>>
>>>>> Just a reminder: clone_fs_devices() still takes the mutex in
>>>>> misc-next.
>>>>    As I am checking clone_fs_devices() does not take any lock.
>>>>   Could you pls recheck?
>>>>
>>>
>>> Hmmmm... misc-next:
>>>
>>> https://github.com/kdave/btrfs-devel/blob/e05983195f31374ad51a0f3712efec381397f3cb/fs/btrfs/volumes.c#L381 
>>>
>>
>> Sorry, it should be
>>
>> https://github.com/kdave/btrfs-devel/blob/misc-next/fs/btrfs/volumes.c#L995 
>>
> 
> 
>   Some of the Git commands stopped working. I had to run git fsck.
>   Now I see mutex in close_fs_devices(), not sure if I was blind to it 
> before.
>   Anyway, this is a bad patch. I am working to fix it.
> 

  Git errors were distracting. But why I didn't see the 
device_list_mutex is because I had the following patch [1] in my 
workspace, which is not yet integrated to the misc-next / commented.

  [1] btrfs: fix lockdep warning while mounting sprout fs
 
https://lore.kernel.org/linux-btrfs/8325002d-f8a6-a9b7-a27d-4cf62cbbc672@oracle.com/

  So as of now, I can say this patch needs the above patch.

  Could you please apply the above patch before this patch for tests?

Thanks, Anand