On Fri, Oct 28, 2011 at 09:53:53AM +0200, Miklos Szeredi wrote: > On Fri, 2011-10-28 at 02:08 -0400, Christoph Hellwig wrote: > > This one gets me a repeated spew of WARN_ONs during XFS log recover, > > repeating the following pattern: > > The assumption here is that set_nlink() is called with a non-zero count. > The point of introducing set_nlink() was to verify this assumption, > otherwise pending delete accounting will be screwed up. > > If setting i_nlink to zero is not a bug in xfs we can do two things: > > 1) do a conditional clear_nlink() in xfs_setup_inode() to document that > nlink can indeed be zero > > 2) remove the warning from set_nlink(). That may hide some cases where > i_nlink was cleared without the intention of the filesystem but it will > work just fine wrt. the pending delete accounting. I suspect 2 might be the better option. The pattern we see here in XFS is pretty typical for transactional filesytems - when we mount a filesystem after an unclean shutdown we need to drop all inodes that were open but unlinked when the system crashed, and that typically means reading inodes from disk that have a zero i_nlink. Maybe some filesystems never instanciate a VFS inode for it, but I suspect many do. For XFS we will actually see it during regularly testing as we have an ioctl that simulates a shutdown and can thus trigger log recovery easily, while for others like ext4 you'd actually have to do a real reset of your (physical or virtual) machine. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
