h_mutex held: rbd_register_watch __rbd_register_watch ceph_osdc_watch linger_reg_commit_wait It's waiting for lreq->reg_commit_wait to be completed, but for that to happen the respective request needs to end up on need_resend_linger list and be kicked when requests are unpaused. There is no chance for that if the request in question is never marked paused in the first place. The fact that rbd_dev->watch_mutex remains taken out forever then prevents the image from getting unmapped -- "rbd unmap" would inevitably hang in D state on an attempt to grab the mutex. Cc: stable@vger.kernel.org Reported-by: Raphael Zimmer Signed-off-by: Ilya Dryomov Reviewed-by: Viacheslav Dubeyko Signed-off-by: Greg Kroah-Hartman --- net/ceph/osd_client.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) --- a/net/ceph/osd_client.c +++ b/net/ceph/osd_client.c @@ -1529,6 +1529,7 @@ static enum calc_target_result calc_targ struct ceph_pg_pool_info *pi; struct ceph_pg pgid, last_pgid; struct ceph_osds up, acting; + bool should_be_paused; bool is_read = t->flags & CEPH_OSD_FLAG_READ; bool is_write = t->flags & CEPH_OSD_FLAG_WRITE; bool force_resend = false; @@ -1597,10 +1598,16 @@ static enum calc_target_result calc_targ &last_pgid)) force_resend = true; - if (t->paused && !target_should_be_paused(osdc, t, pi)) { - t->paused = false; + should_be_paused = target_should_be_paused(osdc, t, pi); + if (t->paused && !should_be_paused) { unpaused = true; } + if (t->paused != should_be_paused) { + dout("%s t %p paused %d -> %d\n", __func__, t, t->paused, + should_be_paused); + t->paused = should_be_paused; + } + legacy_change = ceph_pg_compare(&t->pgid, &pgid) || ceph_osds_changed(&t->acting, &acting, t->used_replica || any_change);[PATCH 6.1 14/72] libceph: make calc_target() set t->paused, not just clear itGreg Kroah-Hartman undefinedstable@vger.kernel.org undefined undefined undefined undefined undefined’N…›