The driver may sleep under a spin lock, and the function call path is:
cfs_wi_scheduler (acquire the lock by spin_lock)
  LASSERT
    lbug_with_loc
      libcfs_debug_dumplog
        schedule and kthread_run --> may sleep

To fix it, all "LASSERT" is placed out of the spin_lock and spin_unlock.

Signed-off-by: Jia-Ju Bai <baijiaju1...@163.com>
---
 drivers/staging/lustre/lnet/libcfs/workitem.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/lustre/lnet/libcfs/workitem.c 
b/drivers/staging/lustre/lnet/libcfs/workitem.c
index dbc2a9b..9f7832e 100644
--- a/drivers/staging/lustre/lnet/libcfs/workitem.c
+++ b/drivers/staging/lustre/lnet/libcfs/workitem.c
@@ -212,9 +212,9 @@ static int cfs_wi_scheduler(void *arg)
                        CWARN("Unable to bind %s on CPU partition %d\n",
                              sched->ws_name, sched->ws_cpt);
 
+       LASSERT(sched->ws_starting == 1);
        spin_lock(&cfs_wi_data.wi_glock);
 
-       LASSERT(sched->ws_starting == 1);
        sched->ws_starting--;
        sched->ws_nthreads++;
 
@@ -231,11 +231,14 @@ static int cfs_wi_scheduler(void *arg)
                       nloops < CFS_WI_RESCHED) {
                        wi = list_entry(sched->ws_runq.next,
                                        struct cfs_workitem, wi_list);
+
+                       spin_unlock(&sched->ws_lock);
                        LASSERT(wi->wi_scheduled && !wi->wi_running);
+                       LASSERT(sched->ws_nscheduled > 0);
+                       spin_lock(&sched->ws_lock);
 
                        list_del_init(&wi->wi_list);
 
-                       LASSERT(sched->ws_nscheduled > 0);
                        sched->ws_nscheduled--;
 
                        wi->wi_running = 1;
@@ -254,7 +257,10 @@ static int cfs_wi_scheduler(void *arg)
                        if (list_empty(&wi->wi_list))
                                continue;
 
+                       spin_unlock(&sched->ws_lock);
                        LASSERT(wi->wi_scheduled);
+                       spin_lock(&sched->ws_lock);
+
                        /* wi is rescheduled, should be on rerunq now, we
                         * move it to runq so it can run action now
                         */
-- 
1.7.9.5


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