On Tue, May 2, 2017 at 10:30 AM, Christoph Hellwig <hch@xxxxxx> wrote: > On Fri, Apr 28, 2017 at 05:00:01PM +0300, Amir Goldstein wrote: >> Copy the uuid of the filesystem to struct super_block s_uuid field, >> as several other filesystems already do. Copy regardless of the nouuid >> mount option, because other filesystems also do not guaranty uniqueness >> of the s_uuid field in super_block struct. > > No guaranteeing uniqueness will create problems, don't do that. How can it create problems if uniqueness is not guaranteed with Current s_uuid? Even if we did make the xfs uuid table code generic It couldn't be the vfs default. Filesystems will have to opt in. > > Other file system didn't use to do the uuid table check that XFS did > either, and that's a fatal bug. In the long run we'll need to move > this check to the VFS now that we have s_uuid. > > Also while checking for a nul uuid is probably ok we need to formalize > that at least that the check is needed. Preferably by adding a little > inline helper for it, and documenting it. Makes sense. I'll post a patch.
