On Tue, Jan 10, 2012 at 09:17:06PM +0100, Jan Kara wrote: > On Tue 10-01-12 13:12:55, Josef Bacik wrote: > > If we are journalling data (ie journal=data or big symlinks) we can discard > > buffers and move them to different transactions to make sure they get cleaned up > > properly. The problem is b_modified could still be set from the last > > transaction that touched it, so putting it on the currently running transaction > > or setting it up to be put on the next transaction will run into problems if the > > buffer gets reused in that transaction as the space accounting logic won't be > > done, which will result in panics at commit time because t_nr_buffers will end > > up being more than t_outstanding_credits. Thanks to Jan Kara for pointing out > > the other part of this problem a few months ago. Thanks, > Ho hum, I'm inclined to apply this just because it makes sense. But I > still don't see how a transaction can reuse a buffer from BJ_Forget list. > We attach there only truncated buffers and their underlying block can be > reallocated only after the transaction freeing them is committed. So have > you some incentive that this patch indeed fixes the t_outstanding_credits > assertion you were hunting? > So more the problem is where we set b_next_transaction, since it could be reallocated in the next transaction after the current transaction commits and then we're really screwed. I have no real evidence to prove that this is causing my problem yet, but it's definitely wrong and I want to get it fixed before I forget it :). Thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
