This is a note to let you know that I've just added the patch titled
gfs2: Don't call dlm after protocol is unmounted
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
gfs2-don-t-call-dlm-after-protocol-is-unmounted.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 56f89ad64e260b5d075f1adbb972cf038c81d043
Author: Bob Peterson <rpeterso@xxxxxxxxxx>
Date: Fri Jul 30 12:41:49 2021 -0500
gfs2: Don't call dlm after protocol is unmounted
[ Upstream commit d1340f80f0b8066321b499a376780da00560e857 ]
In the gfs2 withdraw sequence, the dlm protocol is unmounted with a call
to lm_unmount. After a withdraw, users are allowed to unmount the
withdrawn file system. But at that point we may still have glocks left
over that we need to free via unmount's call to gfs2_gl_hash_clear.
These glocks may have never been completed because of whatever problem
caused the withdraw (IO errors or whatever).
Before this patch, function gdlm_put_lock would still try to call into
dlm to unlock these leftover glocks, which resulted in dlm returning
-EINVAL because the lock space was abandoned. These glocks were never
freed because there was no mechanism after that to free them.
This patch adds a check to gdlm_put_lock to see if the locking protocol
was inactive (DFL_UNMOUNT flag) and if so, free the glock and not
make the invalid call into dlm.
I could have combined this "if" with the one that follows, related to
leftover glock LVBs, but I felt the code was more readable with its own
if clause.
Signed-off-by: Bob Peterson <rpeterso@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c
index 56dddc1f8ddd..9e90e42c495e 100644
--- a/fs/gfs2/lock_dlm.c
+++ b/fs/gfs2/lock_dlm.c
@@ -295,6 +295,11 @@ static void gdlm_put_lock(struct gfs2_glock *gl)
gfs2_sbstats_inc(gl, GFS2_LKS_DCOUNT);
gfs2_update_request_times(gl);
+ /* don't want to call dlm if we've unmounted the lock protocol */
+ if (test_bit(DFL_UNMOUNT, &ls->ls_recover_flags)) {
+ gfs2_glock_free(gl);
+ return;
+ }
/* don't want to skip dlm_unlock writing the lvb when lock has one */
if (test_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags) &&
