4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ming Lei tom.leiming@gmail.com
[ Upstream commit 737f98cfe7de8df7433a4d846850aa8efa44bd48 ]
Both q->mq_kobj and sw queues' kobjects should have been initialized once, instead of doing that each add_disk context.
Also this patch removes clearing of ctx in blk_mq_init_cpu_queues() because percpu allocator fills zero to allocated variable.
This patch fixes one issue[1] reported from Omar.
[1] kernel wearning when doing unbind/bind on one scsi-mq device
[ 19.347924] kobject (ffff8800791ea0b8): tried to init an initialized object, something is seriously wrong. [ 19.349781] CPU: 1 PID: 84 Comm: kworker/u8:1 Not tainted 4.10.0-rc7-00210-g53f39eeaa263 #34 [ 19.350686] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-20161122_114906-anatol 04/01/2014 [ 19.350920] Workqueue: events_unbound async_run_entry_fn [ 19.350920] Call Trace: [ 19.350920] dump_stack+0x63/0x83 [ 19.350920] kobject_init+0x77/0x90 [ 19.350920] blk_mq_register_dev+0x40/0x130 [ 19.350920] blk_register_queue+0xb6/0x190 [ 19.350920] device_add_disk+0x1ec/0x4b0 [ 19.350920] sd_probe_async+0x10d/0x1c0 [sd_mod] [ 19.350920] async_run_entry_fn+0x48/0x150 [ 19.350920] process_one_work+0x1d0/0x480 [ 19.350920] worker_thread+0x48/0x4e0 [ 19.350920] kthread+0x101/0x140 [ 19.350920] ? process_one_work+0x480/0x480 [ 19.350920] ? kthread_create_on_node+0x60/0x60 [ 19.350920] ret_from_fork+0x2c/0x40
Cc: Omar Sandoval osandov@osandov.com Signed-off-by: Ming Lei tom.leiming@gmail.com Tested-by: Peter Zijlstra (Intel) peterz@infradead.org Signed-off-by: Jens Axboe axboe@fb.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- block/blk-mq-sysfs.c | 4 +--- block/blk-mq.c | 4 +++- block/blk-mq.h | 1 + 3 files changed, 5 insertions(+), 4 deletions(-)
--- a/block/blk-mq-sysfs.c +++ b/block/blk-mq-sysfs.c @@ -429,7 +429,7 @@ void blk_mq_hctx_kobj_init(struct blk_mq kobject_init(&hctx->kobj, &blk_mq_hw_ktype); }
-static void blk_mq_sysfs_init(struct request_queue *q) +void blk_mq_sysfs_init(struct request_queue *q) { struct blk_mq_ctx *ctx; int cpu; @@ -449,8 +449,6 @@ int blk_mq_register_dev(struct device *d
blk_mq_disable_hotplug();
- blk_mq_sysfs_init(q); - ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq"); if (ret < 0) goto out; --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1707,7 +1707,6 @@ static void blk_mq_init_cpu_queues(struc struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i); struct blk_mq_hw_ctx *hctx;
- memset(__ctx, 0, sizeof(*__ctx)); __ctx->cpu = i; spin_lock_init(&__ctx->lock); INIT_LIST_HEAD(&__ctx->rq_list); @@ -1970,6 +1969,9 @@ struct request_queue *blk_mq_init_alloca if (!q->queue_ctx) goto err_exit;
+ /* init q->mq_kobj and sw queues' kobjects */ + blk_mq_sysfs_init(q); + q->queue_hw_ctx = kzalloc_node(nr_cpu_ids * sizeof(*(q->queue_hw_ctx)), GFP_KERNEL, set->numa_node); if (!q->queue_hw_ctx) --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -50,6 +50,7 @@ static inline struct blk_mq_hw_ctx *blk_ /* * sysfs helpers */ +extern void blk_mq_sysfs_init(struct request_queue *q); extern int blk_mq_sysfs_register(struct request_queue *q); extern void blk_mq_sysfs_unregister(struct request_queue *q); extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);