Re: [PATCH 01/13] nbd: use the correct block_device in nbd_ioctl

[Jan Kara <jack@suse.cz>]

On Thu 24-03-22 18:11:48, Christoph Hellwig wrote:
> On Thu, Mar 24, 2022 at 02:23:22PM +0100, Jan Kara wrote:
> > Should't we call __invalidate_device() for the partition bdev here? Because
> > if the NBD device has partitions, filesystem will be mounted on this
> > partition and we want to invalidate it. Similarly the partition buffer
> > cache is different from the buffer cache of the whole device and we should
> > invalidate the partition one. In fact in cases like this I think we need
> > to invalidate all the partitions and filesystems that are there on this
> > disk so neither the old, nor the new code looks quite correct to me. Am I
> > missing something?
> 
> Well, that assumes just one partition is used, which kinda defeats the
> purpose of partitions.  I can exclude the __invalidate_device to not
> change from one kind of broken to another, but I suspect the real
> question is why we have this __invalidate_device call at all.

I suppose it tries to cleanup after effectively hot-unplugging the device.
But I think we don't need to untangle that in this patch set. I'd just
prefer we would not change one questionable behavior for another similarly
questionable one...

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR