On Mon, Feb 7, 2011 at 10:52 AM, Jim Schutt <jaschut@xxxxxxxxxx> wrote: > > On Wed, 2011-01-26 at 22:18 -0700, Nick Piggin wrote: >> On Wed, Jan 26, 2011 at 9:10 AM, Yehuda Sadeh Weinraub >> <yehudasa@xxxxxxxxx> wrote: >> > On Wed, Jan 19, 2011 at 2:32 PM, Nick Piggin <npiggin@xxxxxxxxx> wrote: >> >> On Thu, Jan 20, 2011 at 9:27 AM, Yehuda Sadeh Weinraub >> >> <yehudasa@xxxxxxxxx> wrote: >> >>> On Tue, Jan 18, 2011 at 2:42 PM, Nick Piggin <npiggin@xxxxxxxxx> wrote: >> >>>> On Wed, Jan 19, 2011 at 9:32 AM, Yehuda Sadeh Weinraub >> >>> >> >>>>> There's an issue with ceph as it references the >> >>>>> dentry->d_parent(->d_inode) at dentry_release(), so setting >> >>>>> dentry->d_parent to NULL here doesn't work with ceph. Though there is >> >>>>> some workaround for it, we would like to be sure that this one is >> >>>>> really required so that we don't exacerbate the ugliness. The >> >>>>> workaround is to keep a pointer to the parent inode in the private >> >>>>> dentry structure, which will be referenced only at the .release() >> >>>>> callback. This is clearly not ideal. >> >>>> >> >>>> Hmm, I'll have to think about it. Probably we can check for >> >>>> d_count == 0 rather than parent != NULL I think? >> >>>> >> >>> >> >>> That'll solve ceph's problem, don't know about how'd affect other >> >>> stuff. We'll need to know whether this is the solution, or whether >> >>> we'd need to introduce some other band aid fix. >> >> >> >> No I think it will work fine. Basically we just need to know whether >> >> we have been deleted, and if so then we restart rather than walking >> >> back up the parent. >> >> >> >> I'll send a patch in a few days. For the meantime, it's a rathe >> >> small window for ceph to worry about. So we'll have something >> >> before -rc2 which should be OK. >> >> >> > >> > I guess that it's a bit late for -rc2, should we assume that it'll be on -rc3? >> >> Yeah, I'm sorry I've been travelling and a bit disconnected. >> >> NFS folk are having a similar problem and looks like similar >> proposed fix will do it. >> >> http://marc.info/?l=linux-fsdevel&m=129599823927039&w=2 >> >> So I think it is the best way to go to restore behaviour back to what >> filesystems already expect, to avoid more surprises in future. > > I think the following BUG indicates I'm hitting this problem? > All I have to do to cause it is unlink a file. > > My ceph client kernel is 8dbdea8444 (master branch) from > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git > + e41cdbb6c5 (master branch) + a3f5274e53 (unstable branch) > from git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git > > Are there any patches available for this I can test? > > Thanks -- Jim > It does look like this specific problem. You can try cherry-pick commit 9c3db35 off the ceph git. It is just a temporary workaround, and it wasn't tested too much. Hopefully Nick will push his fix soon so that it wouldn't be needed. Thanks, Yehuda -- 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
