On Wed, 2010-01-06 at 15:41 -0800, Andrew Morton wrote: > On Thu, 31 Dec 2009 05:59:32 +0900 > OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> wrote: > > > Marvin <marvin24@xxxxxx> writes: > > > > >> Marvin <marvin24@xxxxxx> writes: > > >> > Hi, > > >> > > > >> > I'm getting a lot of these: > > >> > > > >> > kernel: general protection fault: 0000 [#1] SMP > > >> > kernel: last sysfs file: /sys/devices/pci0000:00/0000:00:18.3/modalias > > >> > kernel: CPU 0 > > >> > kernel: Pid: 12177, comm: packagekitd Not tainted 2.6.33-rc2 #1 > > >> > ... > > >> > > > >> > filesystem is ext4 (in case it matters). > > >> > > >> BTW, are you using nfs client on this machine? > > >> > > > > > > um - yes, now that I think about it... I killed a nfs umount process (because of an > > > offline server) shortly before the oopses started to fire. > > > > OK. Probably, this oops would be same with one which happened on my > > machine recently. That path in patch corrupts dcache hash, so it can be > > the cause of strange behavior or oops on dcache hash. > > > > If so, the attached patch would fix it. > > > > Thanks. > > -- > > OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> > > > > > > Recent change is missing to update "rehash". With that change, it will > > become the cause of adding dentry to hash twice. > > > > This explains the reason of Oops (dereference the freed dentry in > > __d_lookup()) on my machine. > > > > Signed-off-by: OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> > > --- > > > > fs/nfs/dir.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff -puN fs/nfs/dir.c~nfs-d_rehash-fix fs/nfs/dir.c > > --- linux-2.6/fs/nfs/dir.c~nfs-d_rehash-fix 2009-12-28 06:18:09.000000000 +0900 > > +++ linux-2.6-hirofumi/fs/nfs/dir.c 2009-12-28 06:18:16.000000000 +0900 > > @@ -1615,6 +1615,7 @@ static int nfs_rename(struct inode *old_ > > goto out; > > > > new_dentry = dentry; > > + rehash = NULL; > > new_inode = NULL; > > } > > } > > Guys, what's the status of this fix? Did Marvin have a chance to test > it? Are the NFS developers aware of it? > > Thanks. > Sorry for the delay. The above fix looks correct to me, but I too would like a confirmation that it fixes the Oops before I push it to Linus. In the meantime, I've committed it to my linux-next branch. Cheers Trond -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
