Hello, I've been into a source of lockdep warning I got with XFS when testing my filesystem freezing patches. The culprit seems to be that when doing direct IO, XFS starts a transaction in xfs_setfilesize_trans_alloc() and attaches that transaction to endio structure. Then it goes on and starts another transaction in xfs_iomap_write_direct() which creates a possible deadlock with filesystem freezing (if the second transaction start happens after we start blocking new transactions, it gets blocked, but the first transaction isn't ever completed). So first I wanted to ask whether my analysis is correct. If yes, I was also wondering whether this cannot cause a deadlock (at least in theory) if the second transaction would block waiting for log space but we couldn't possibly free enough of it due to the first transaction being held open? If freezing deadlock is the only problem with this code, then I guess we could avoid waiting for filesystem freezing when starting the second transaction (although it might end up being rather ugly). Or if anyone else has other idea how to solve this, I'm listening ;). Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
