Re: [dm-devel] DM's filesystem lookup in dm_get_dev_t() [was: Re: linux-next: manual merge of the device-mapper tree with Linus' tree]

From: Christoph Hellwig
Date: Wed Dec 23 2020 - 03:07:38 EST


On Tue, Dec 22, 2020 at 09:06:04PM +0000, Alasdair G Kergon wrote:
> I have not read the background about whatever the new problem is - I'm
> jumping in cold seeing this message - but from the very beginning of
> device-mapper we have strongly recommended that userspace supplies the
> block device in the form MAJOR:MINOR and all our own tools do that. We
> guarantee not to deadlock in these places when this is done.
>
> We also accept the device in the form of a path name as we know there
> are times when this is safe and convenient, but then we offer no
> guarantees - we place the responsibility upon userspace only to do this
> when it knows it is safe to do so i.e. no race and no deadlock.

644bda6f346038bce7ad3ed48f7044c10dde6d47 changes that by accepting all
kinds of weirdo formats :(