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. > > > > To avoid this issue and still be able to perform time-consuming checks > > at open() time the block device driver can provide open_finish(). If it > > does opening the device proceeds even when an error is returned from > > open(), bd_mutex is released and open_finish() is called. If > > open_finish() succeeds the device is now open, if it fails release() is > > called. > > > > When -ERESTARTSYS is returned from open() blkdev_get may loop without > > calling open_finish(). On -ERESTARTSYS open_finish() is not called. > > > > Move a ret = 0 assignment up in the if/else branching to avoid returning > > -ENXIO. Previously the return value was ignored on the unhandled branch. > > This just doesn't make much sense. There is no point in messing up > the block API for ugly workarounds like that. If you have ideas how to do this better then share them. Thanks Michal