On Mon, Oct 17, 2016 at 10:24:13PM -0700, Christoph Hellwig wrote: > On Mon, Oct 17, 2016 at 06:10:51PM -0700, Darrick J. Wong wrote: > > As part of the inode block map intent log item recovery process, we had > > to set the IRECOVERY flag to prevent an unlinked inode from being > > truncated during the first iput call. This required us to set MS_ACTIVE > > so that iput puts the inode on the lru instead of immediately evicting > > the inode. > > > > Unfortunately, if the mount fails later on, the inodes that have been > > loaded (root dir and realtime) actually need to be evicted since we're > > aborting the mount. If we don't clear MS_ACTIVE in the failure step, > > those inodes are not evicted and therefore leak. The leak was found > > by running xfs/130 and rmmoding xfs immediately after the test. > > Actually that was an item I wanted to sort out about reflink before > we got it merged.. > > Can you explain why we even added the MS_ACTIVE flag? Is it > to fool iput_final into keeping the inode on the lru? In a way, yes. We don't need to keep it on the LRU necessarily, we just need it not to think "Oh, this inode has i_nlink == 0 so we can truncate all the blocks and free the inode" prior to the end of bmap intent processing. > I'd really prefer if we could just do it in our own ->drop_inode call > then instead of messing with MS_ACTIVE. The difficulty here is that without MS_ACTIVE, the vfs will always evict the inode when i_count == 0. I suppose bmap intent processing could bump up i_count and stash the inode somewhere to prevent the i_count from hitting zero until after we're done recovering the log... ...but otherwise I'm sorta stumped about how to do that. (Not so much 'stumped' as 'getting a headcold', bleargh) --D -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
