Re: [PATCH net 1/2] vhost: use mutex_lock_nested() in vhost_dev_lock_vqs()

[David Miller]

From: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Date: Wed, 24 Jan 2018 23:46:19 +0200

> On Wed, Jan 24, 2018 at 04:38:30PM -0500, David Miller wrote:
>> From: Jason Wang <jasowang@xxxxxxxxxx>
>> Date: Tue, 23 Jan 2018 17:27:25 +0800
>> 
>> > We used to call mutex_lock() in vhost_dev_lock_vqs() which tries to
>> > hold mutexes of all virtqueues. This may confuse lockdep to report a
>> > possible deadlock because of trying to hold locks belong to same
>> > class. Switch to use mutex_lock_nested() to avoid false positive.
>> > 
>> > Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API")
>> > Reported-by: syzbot+dbb7c1161485e61b0241@xxxxxxxxxxxxxxxxxxxxxxxxx
>> > Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
>> 
>> Michael, I see you ACK'd this, meaning that you're OK with these two
>> fixes going via my net tree?
>> 
>> Thanks.
> 
> Yes - this seems to be what Jason wanted (judging by the net
> tag in the subject) and I'm fine with it.
> Thanks a lot.

Great, not a problem, done.