From f39e7d3aae2934b1cfdd209b54c508e2552e9531 Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Tue, 24 Nov 2020 10:41:40 -0600 Subject: gfs2: Don't freeze the file system during unmount GFS2's freeze/thaw mechanism uses a special freeze glock to control its operation. It does this with a sync glock operation (glops.c) called freeze_go_sync. When the freeze glock is demoted (glock's do_xmote) the glops function causes the file system to be frozen. This is intended. However, GFS2's mount and unmount processes also hold the freeze glock to prevent other processes, perhaps on different cluster nodes, from mounting the frozen file system in read-write mode. Before this patch, there was no check in freeze_go_sync for whether a freeze in intended or whether the glock demote was caused by a normal unmount. So it was trying to freeze the file system it's trying to unmount, which ends up in a deadlock. This patch adds an additional check to freeze_go_sync so that demotes of the freeze glock are ignored if they come from the unmount process. Fixes: 20b329129009 ("gfs2: Fix regression in freeze_go_sync") Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher --- fs/gfs2/glops.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/gfs2') diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c index e2cfc00ab936..3faa421568b0 100644 --- a/fs/gfs2/glops.c +++ b/fs/gfs2/glops.c @@ -582,7 +582,8 @@ static int freeze_go_sync(struct gfs2_glock *gl) * Once thawed, the work func acquires the freeze glock in * SH and everybody goes back to thawed. */ - if (gl->gl_state == LM_ST_SHARED && !gfs2_withdrawn(sdp)) { + if (gl->gl_state == LM_ST_SHARED && !gfs2_withdrawn(sdp) && + !test_bit(SDF_NORECOVERY, &sdp->sd_flags)) { atomic_set(&sdp->sd_freeze_state, SFS_STARTING_FREEZE); error = freeze_super(sdp->sd_vfs); if (error) { -- cgit v1.2.3