diff options
Diffstat (limited to 'debian/patches-rt/0185-block-blk-mq-move-blk_queue_usage_counter_release-in.patch')
| -rw-r--r-- | debian/patches-rt/0185-block-blk-mq-move-blk_queue_usage_counter_release-in.patch | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/debian/patches-rt/0185-block-blk-mq-move-blk_queue_usage_counter_release-in.patch b/debian/patches-rt/0185-block-blk-mq-move-blk_queue_usage_counter_release-in.patch new file mode 100644 index 000000000..802e53619 --- /dev/null +++ b/debian/patches-rt/0185-block-blk-mq-move-blk_queue_usage_counter_release-in.patch @@ -0,0 +1,120 @@ +From 3c180d9b5b9620bc5c18e0a7fb9f02059b333db3 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Tue, 13 Mar 2018 13:49:16 +0100 +Subject: [PATCH 185/347] block: blk-mq: move blk_queue_usage_counter_release() + into process context +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +| BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:914 +| in_atomic(): 1, irqs_disabled(): 0, pid: 255, name: kworker/u257:6 +| 5 locks held by kworker/u257:6/255: +| #0: ("events_unbound"){.+.+.+}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0 +| #1: ((&entry->work)){+.+.+.}, at: [<ffffffff8108edf1>] process_one_work+0x171/0x5e0 +| #2: (&shost->scan_mutex){+.+.+.}, at: [<ffffffffa000faa3>] __scsi_add_device+0xa3/0x130 [scsi_mod] +| #3: (&set->tag_list_lock){+.+...}, at: [<ffffffff812f09fa>] blk_mq_init_queue+0x96a/0xa50 +| #4: (rcu_read_lock_sched){......}, at: [<ffffffff8132887d>] percpu_ref_kill_and_confirm+0x1d/0x120 +| Preemption disabled at:[<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70 +| +| CPU: 2 PID: 255 Comm: kworker/u257:6 Not tainted 3.18.7-rt0+ #1 +| Workqueue: events_unbound async_run_entry_fn +| 0000000000000003 ffff8800bc29f998 ffffffff815b3a12 0000000000000000 +| 0000000000000000 ffff8800bc29f9b8 ffffffff8109aa16 ffff8800bc29fa28 +| ffff8800bc5d1bc8 ffff8800bc29f9e8 ffffffff815b8dd4 ffff880000000000 +| Call Trace: +| [<ffffffff815b3a12>] dump_stack+0x4f/0x7c +| [<ffffffff8109aa16>] __might_sleep+0x116/0x190 +| [<ffffffff815b8dd4>] rt_spin_lock+0x24/0x60 +| [<ffffffff810b6089>] __wake_up+0x29/0x60 +| [<ffffffff812ee06e>] blk_mq_usage_counter_release+0x1e/0x20 +| [<ffffffff81328966>] percpu_ref_kill_and_confirm+0x106/0x120 +| [<ffffffff812eff76>] blk_mq_freeze_queue_start+0x56/0x70 +| [<ffffffff812f0000>] blk_mq_update_tag_set_depth+0x40/0xd0 +| [<ffffffff812f0a1c>] blk_mq_init_queue+0x98c/0xa50 +| [<ffffffffa000dcf0>] scsi_mq_alloc_queue+0x20/0x60 [scsi_mod] +| [<ffffffffa000ea35>] scsi_alloc_sdev+0x2f5/0x370 [scsi_mod] +| [<ffffffffa000f494>] scsi_probe_and_add_lun+0x9e4/0xdd0 [scsi_mod] +| [<ffffffffa000fb26>] __scsi_add_device+0x126/0x130 [scsi_mod] +| [<ffffffffa013033f>] ata_scsi_scan_host+0xaf/0x200 [libata] +| [<ffffffffa012b5b6>] async_port_probe+0x46/0x60 [libata] +| [<ffffffff810978fb>] async_run_entry_fn+0x3b/0xf0 +| [<ffffffff8108ee81>] process_one_work+0x201/0x5e0 + +percpu_ref_kill_and_confirm() invokes blk_mq_usage_counter_release() in +a rcu-sched region. swait based wake queue can't be used due to +wake_up_all() usage and disabled interrupts in !RT configs (as reported +by Corey Minyard). +The wq_has_sleeper() check has been suggested by Peter Zijlstra. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + block/blk-core.c | 14 +++++++++++++- + include/linux/blkdev.h | 2 ++ + 2 files changed, 15 insertions(+), 1 deletion(-) + +diff --git a/block/blk-core.c b/block/blk-core.c +index 461a93c08c14..02835970ef1e 100644 +--- a/block/blk-core.c ++++ b/block/blk-core.c +@@ -973,12 +973,21 @@ void blk_queue_exit(struct request_queue *q) + percpu_ref_put(&q->q_usage_counter); + } + ++static void blk_queue_usage_counter_release_swork(struct swork_event *sev) ++{ ++ struct request_queue *q = ++ container_of(sev, struct request_queue, mq_pcpu_wake); ++ ++ wake_up_all(&q->mq_freeze_wq); ++} ++ + static void blk_queue_usage_counter_release(struct percpu_ref *ref) + { + struct request_queue *q = + container_of(ref, struct request_queue, q_usage_counter); + +- wake_up_all(&q->mq_freeze_wq); ++ if (wq_has_sleeper(&q->mq_freeze_wq)) ++ swork_queue(&q->mq_pcpu_wake); + } + + static void blk_rq_timed_out_timer(struct timer_list *t) +@@ -1078,6 +1087,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id, + queue_flag_set_unlocked(QUEUE_FLAG_BYPASS, q); + + init_waitqueue_head(&q->mq_freeze_wq); ++ INIT_SWORK(&q->mq_pcpu_wake, blk_queue_usage_counter_release_swork); + + /* + * Init percpu_ref in atomic mode so that it's faster to shutdown. +@@ -3967,6 +3977,8 @@ int __init blk_dev_init(void) + if (!kblockd_workqueue) + panic("Failed to create kblockd\n"); + ++ BUG_ON(swork_get()); ++ + request_cachep = kmem_cache_create("blkdev_requests", + sizeof(struct request), 0, SLAB_PANIC, NULL); + +diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h +index 39d90bf9b5fa..0313098a428d 100644 +--- a/include/linux/blkdev.h ++++ b/include/linux/blkdev.h +@@ -27,6 +27,7 @@ + #include <linux/percpu-refcount.h> + #include <linux/scatterlist.h> + #include <linux/blkzoned.h> ++#include <linux/swork.h> + + struct module; + struct scsi_ioctl_command; +@@ -664,6 +665,7 @@ struct request_queue { + #endif + struct rcu_head rcu_head; + wait_queue_head_t mq_freeze_wq; ++ struct swork_event mq_pcpu_wake; + struct percpu_ref q_usage_counter; + struct list_head all_q_node; + +-- +2.36.1 + |