hisi_sas: fix the inconsistent lock issue reported by CONFIG_PROVE_LOCKING
authorJohn Garry <john.garry@huawei.com>
Tue, 31 May 2016 12:38:50 +0000 (20:38 +0800)
committerMartin K. Petersen <martin.petersen@oracle.com>
Wed, 13 Jul 2016 03:16:31 +0000 (23:16 -0400)
It is not necessary to surround call to
notify_port_event(, PORTE_BROADCAST_RCVD) by spin_lock_irqsave(),
so remove.
This was causing a warn, as below:

    =================================
    [ 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 <xuwei5@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/hisi_sas/hisi_sas_v2_hw.c

index 7d5edd1f4bbae7ec09930e2fc61ce4f9ec4a1bfe..f96560431cf1081af9ea473e67dbe19c30d8af23 100644 (file)
@@ -1912,14 +1912,9 @@ static void phy_bcast_v2_hw(int phy_no, struct hisi_hba *hisi_hba)
        struct hisi_sas_phy *phy = &hisi_hba->phy[phy_no];
        struct asd_sas_phy *sas_phy = &phy->sas_phy;
        struct sas_ha_struct *sas_ha = &hisi_hba->sha;
-       unsigned long flags;
 
        hisi_sas_phy_write32(hisi_hba, phy_no, SL_RX_BCAST_CHK_MSK, 1);
-
-       spin_lock_irqsave(&hisi_hba->lock, flags);
        sas_ha->notify_port_event(sas_phy, PORTE_BROADCAST_RCVD);
-       spin_unlock_irqrestore(&hisi_hba->lock, flags);
-
        hisi_sas_phy_write32(hisi_hba, phy_no, CHL_INT0,
                             CHL_INT0_SL_RX_BCST_ACK_MSK);
        hisi_sas_phy_write32(hisi_hba, phy_no, SL_RX_BCAST_CHK_MSK, 0);