hisi_sas: fix the inconsistent lock issue reported by CONFIG_PROVE_LO…

…CKING

The log is as blow:

=================================
[ INFO: inconsistent lock state ]
4.4.8+ #12 Not tainted
---------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
kworker/u64:1/168 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&(&hisi_hba->lock)->rlock){?.....}, at: [<ffffffc00052c708>] alloc_dev_quirk_v2_hw+0x48/0xec
{IN-HARDIRQ-W} state was registered at:
  [<ffffffc0000fc764>] mark_lock+0x19c/0x6a0
  [<ffffffc0000fdc14>] __lock_acquire+0xa2c/0x1d00
  [<ffffffc0000ff654>] lock_acquire+0x58/0x7c
  [<ffffffc0008b609c>] _raw_spin_lock_irqsave+0x54/0x6c
  [<ffffffc00052d3c0>] int_chnl_int_v2_hw+0x1c4/0x248
  [<ffffffc0001098e8>] handle_irq_event_percpu+0x9c/0x144
  [<ffffffc0001099d4>] handle_irq_event+0x44/0x74
  [<ffffffc00010cd68>] handle_fasteoi_irq+0xb4/0x188
  [<ffffffc000108ea8>] generic_handle_irq+0x24/0x38
  [<ffffffc0001091fc>] __handle_domain_irq+0x60/0xac
  [<ffffffc00008261c>] gic_handle_irq+0xcc/0x168
  [<ffffffc0000855ac>] el1_irq+0x6c/0xe0
  [<ffffffc0000f7414>] default_idle_call+0x1c/0x34
  [<ffffffc0000f7654>] cpu_startup_entry+0x1d4/0x228
  [<ffffffc0008aecd8>] rest_init+0x150/0x160
  [<ffffffc000c4b95c>] start_kernel+0x3a4/0x3b8
  [<00000000008bb000>] 0x8bb000
irq event stamp: 32661
hardirqs last  enabled at (32661): [<ffffffc0008b41a8>] __mutex_unlock_slowpath+0x108/0x18c
hardirqs last disabled at (32660): [<ffffffc0008b40e4>] __mutex_unlock_slowpath+0x44/0x18c
softirqs last  enabled at (25114): [<ffffffc0000bde68>] __do_softirq+0x210/0x27c
softirqs last disabled at (25095): [<ffffffc0000be224>] irq_exit+0x9c/0xe8

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&hisi_hba->lock)->rlock);
  <Interrupt>
    lock(&(&hisi_hba->lock)->rlock);

 *** DEADLOCK ***

2 locks held by kworker/u64:1/168:
 #0:  ("%s"shost->work_q_name){++++.+}, at: [<ffffffc0000d2980>] process_one_work+0x134/0x3cc
 #1:  ((&sw->work)#2){+.+.+.}, at: [<ffffffc0000d2980>] process_one_work+0x134/0x3cc

stack backtrace:
CPU: 4 PID: 168 Comm: kworker/u64:1 Not tainted 4.4.8+ #12
Hardware name: Huawei Technologies Co., Ltd. D03/D03, BIOS 1.12 01/01/1900
Workqueue: scsi_wq_1 sas_discover_domain
Call trace:
[<ffffffc000089988>] dump_backtrace+0x0/0x114
[<ffffffc000089ab0>] show_stack+0x14/0x1c
[<ffffffc00035ac50>] dump_stack+0xb4/0xf0
[<ffffffc0000fc524>] print_usage_bug+0x210/0x2b4
[<ffffffc0000fcbc4>] mark_lock+0x5fc/0x6a0
[<ffffffc0000fd9e8>] __lock_acquire+0x800/0x1d00
[<ffffffc0000ff654>] lock_acquire+0x58/0x7c
[<ffffffc0008b5edc>] _raw_spin_lock+0x44/0x58
[<ffffffc00052c708>] alloc_dev_quirk_v2_hw+0x48/0xec
[<ffffffc000528214>] hisi_sas_dev_found+0x48/0x1b8
[<ffffffc00051a9b8>] sas_notify_lldd_dev_found+0x34/0xe0
[<ffffffc00051e5e8>] sas_discover_root_expander+0x58/0x128
[<ffffffc00051b38c>] sas_discover_domain+0x4bc/0x564
[<ffffffc0000d29ec>] process_one_work+0x1a0/0x3cc
[<ffffffc0000d2d50>] worker_thread+0x138/0x438
[<ffffffc0000d9494>] kthread+0xdc/0xf0
[<ffffffc000085c50>] ret_from_fork+0x10/0x40

Signed-off-by: Wei Xu <[email protected]>
Reviewed-by: John Garry <[email protected]>

drivers/scsi/hisi_sas/hisi_sas_v2_hw.c

@@ -499,7 +499,6 @@ hisi_sas_device *alloc_dev_quirk_v2_hw(struct domain_device *device)
 	struct hisi_sas_device *sas_dev = NULL;
 	int i, sata_dev = dev_is_sata(device);
 
-	spin_lock(&hisi_hba->lock);
 	for (i = 0; i < HISI_SAS_MAX_DEVICES; i++) {
 		/*
 		 * SATA device id bit0 should be 0
@@ -516,7 +515,6 @@ hisi_sas_device *alloc_dev_quirk_v2_hw(struct domain_device *device)
 			break;
 		}
 	}
-	spin_unlock(&hisi_hba->lock);
 
 	return sas_dev;
 }