Re: [PATCH v2 6/8] bdev: add open_finish.

[Matthew Wilcox]

On Thu, Oct 24, 2019 at 10:55:14AM +0200, Michal Suchánek wrote:
> On Wed, Oct 23, 2019 at 07:22:32PM -0700, Christoph Hellwig wrote:
> > On Wed, Oct 23, 2019 at 02:52:45PM +0200, Michal Suchanek wrote:
> > > Opening a block device may require a long operation such as waiting for
> > > the cdrom tray to close. Performing this operation with locks held locks
> > > out other attempts to open the device. These processes waiting to open
> > > the device are not killable.

You can use mutex_lock_killable() to fix that.