From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Date: Mon, 5 Apr 2021 12:03:45 -0400 Subject: [Cluster-devel] [PATCH AUTOSEL 5.11 02/22] gfs2: Flag a withdraw if init_threads() fails In-Reply-To: <20210405160406.268132-1-sashal@kernel.org> References: <20210405160406.268132-1-sashal@kernel.org> Message-ID: <20210405160406.268132-2-sashal@kernel.org> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit From: Andrew Price [ Upstream commit 62dd0f98a0e5668424270b47a0c2e973795faba7 ] Interrupting mount with ^C quickly enough can cause the kthread_run() calls in gfs2's init_threads() to fail and the error path leads to a deadlock on the s_umount rwsem. The abridged chain of events is: [mount path] get_tree_bdev() sget_fc() alloc_super() down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING); [acquired] gfs2_fill_super() gfs2_make_fs_rw() init_threads() kthread_run() ( Interrupted ) [Error path] gfs2_gl_hash_clear() flush_workqueue(glock_workqueue) wait_for_completion() [workqueue context] glock_work_func() run_queue() do_xmote() freeze_go_sync() freeze_super() down_write(&sb->s_umount) [deadlock] In freeze_go_sync() there is a gfs2_withdrawn() check that we can use to make sure freeze_super() is not called in the error path, so add a gfs2_withdraw_delayed() call when init_threads() fails. Ref: https://bugzilla.kernel.org/show_bug.cgi?id=212231 Reported-by: Alexander Aring Signed-off-by: Andrew Price Signed-off-by: Andreas Gruenbacher Signed-off-by: Sasha Levin --- fs/gfs2/super.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index 754ea2a137b4..34ca312457a6 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -169,8 +169,10 @@ int gfs2_make_fs_rw(struct gfs2_sbd *sdp) int error; error = init_threads(sdp); - if (error) + if (error) { + gfs2_withdraw_delayed(sdp); return error; + } j_gl->gl_ops->go_inval(j_gl, DIO_METADATA); if (gfs2_withdrawn(sdp)) { -- 2.30.2