On 05/24/2013 07:18 AM, Andrew Morton wrote: > On Tue, 14 May 2013 17:06:30 +0800 Chen Gang <gang.chen@xxxxxxxxxxx> wrote: > >> > After call collect_mounts(), then call drop_collected_mounts(), it will >> > report an warning: "ida_remove called for id=0 which is not allocated" >> > (one sample is audit_add_tree_rule() in kernel/audit_tree.c). >> > >> > The direct cause (maybe also be the root cause): >> > collect_mounts() passs 'CL_PRIVATE' to copy_tree() -> clone_mnt(). >> > it will set "mnt->mnt_group_id = 0" in clone_mnt(). >> > when drop_collected_mounts() -> mnt_release_group_id(), 'mnt->mnt_group_id == 0'. > I expect this patch also addresses the bug. Can you please review and test it? > I am sure, after apply the patch below, it will be no warning again (fix the direct cause). Originally, I want to fix this bug just like the patch below, but I am not quite sure whether it will hide the real root cause. Thanks. > > From: Takashi Iwai <tiwai@xxxxxxx> > Subject: vfs: fix invalid ida_remove() call > > When the group id of a shared mount is not allocated, the umount still > tries to call mnt_release_group_id(), which eventually hits a kernel > warning at ida_remove() spewing a message like: > > ida_remove called for id=0 which is not allocated. > > This patch fixes the bug simply checking the group id in the caller. > > Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> > Reported-by: Cristian Rodr�guez <crrodriguez@xxxxxxxxxxxx> > Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > --- > > fs/pnode.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff -puN fs/pnode.c~vfs-fix-invalid-ida_remove-call fs/pnode.c > --- a/fs/pnode.c~vfs-fix-invalid-ida_remove-call > +++ a/fs/pnode.c > @@ -83,7 +83,8 @@ static int do_make_slave(struct mount *m > if (peer_mnt == mnt) > peer_mnt = NULL; > } > - if (IS_MNT_SHARED(mnt) && list_empty(&mnt->mnt_share)) > + if (mnt->mnt_group_id && IS_MNT_SHARED(mnt) && > + list_empty(&mnt->mnt_share)) > mnt_release_group_id(mnt); > > list_del_init(&mnt->mnt_share); > _ > > > -- Chen Gang Asianux Corporation -- 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
