From: Joseph Qi <joseph.qi@xxxxxxxxxx> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 5760a97c7143c208fa3a8f8cad0ed7dd672ebd28 upstream. There is a deadlock case which reported by Guozhonghua: https://oss.oracle.com/pipermail/ocfs2-devel/2014-September/010079.html This case is caused by &res->spinlock and &dlm->master_lock misordering in different threads. It was introduced by commit 8d400b81cc83 ("ocfs2/dlm: Clean up refmap helpers"). Since lockres is new, it doesn't not require the &res->spinlock. So remove it. Fixes: 8d400b81cc83 ("ocfs2/dlm: Clean up refmap helpers") Signed-off-by: Joseph Qi <joseph.qi@xxxxxxxxxx> Reviewed-by: joyce.xue <xuejiufei@xxxxxxxxxx> Reported-by: Guozhonghua <guozhonghua@xxxxxxx> Cc: Joel Becker <jlbec@xxxxxxxxxxxx> Cc: Mark Fasheh <mfasheh@xxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- fs/ocfs2/dlm/dlmmaster.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c index cf0f103963b1..673c9bf5debc 100644 --- a/fs/ocfs2/dlm/dlmmaster.c +++ b/fs/ocfs2/dlm/dlmmaster.c @@ -650,12 +650,9 @@ void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm, clear_bit(bit, res->refmap); } - -void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm, +static void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) { - assert_spin_locked(&res->spinlock); - res->inflight_locks++; mlog(0, "%s: res %.*s, inflight++: now %u, %ps()\n", dlm->name, @@ -663,6 +660,13 @@ void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm, __builtin_return_address(0)); } +void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm, + struct dlm_lock_resource *res) +{ + assert_spin_locked(&res->spinlock); + __dlm_lockres_grab_inflight_ref(dlm, res); +} + void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) { @@ -852,10 +856,8 @@ lookup: /* finally add the lockres to its hash bucket */ __dlm_insert_lockres(dlm, res); - /* Grab inflight ref to pin the resource */ - spin_lock(&res->spinlock); - dlm_lockres_grab_inflight_ref(dlm, res); - spin_unlock(&res->spinlock); + /* since this lockres is new it doesn't not require the spinlock */ + __dlm_lockres_grab_inflight_ref(dlm, res); /* get an extra ref on the mle in case this is a BLOCK * if so, the creator of the BLOCK may try to put the last -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html