diff options
Diffstat (limited to 'block/blk-sysfs.c')
| -rw-r--r-- | block/blk-sysfs.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index f3b1968c80ce..55a1bbfef7d4 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -78,8 +78,14 @@ queue_requests_store(struct gendisk *disk, const char *page, size_t count) /* * Serialize updating nr_requests with concurrent queue_requests_store() * and switching elevator. + * + * Use trylock to avoid circular lock dependency with kernfs active + * reference during concurrent disk deletion: + * update_nr_hwq_lock -> kn->active (via del_gendisk -> kobject_del) + * kn->active -> update_nr_hwq_lock (via this sysfs write path) */ - down_write(&set->update_nr_hwq_lock); + if (!down_write_trylock(&set->update_nr_hwq_lock)) + return -EBUSY; if (nr == q->nr_requests) goto unlock; |