This is a note to let you know that I've just added the patch titled gfs2: Flag a withdraw if init_threads() fails to the 5.11-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-flag-a-withdraw-if-init_threads-fails.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f7e0de49b61d9508bf0c59f2feb7e80ce7dc9488 Author: Andrew Price <anprice@xxxxxxxxxx> Date: Mon Mar 15 12:24:00 2021 +0000 gfs2: Flag a withdraw if init_threads() fails [ 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 <aahringo@xxxxxxxxxx> Signed-off-by: Andrew Price <anprice@xxxxxxxxxx> Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> 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)) {