| From: Paul Gortmaker <paul.gortmaker@windriver.com> |
| Date: Sat, 14 Feb 2015 11:01:16 -0500 |
| Subject: sas-ata/isci: dont't disable interrupts in qc_issue handler |
| |
| On 3.14-rt we see the following trace on Canoe Pass for |
| SCSI_ISCI "Intel(R) C600 Series Chipset SAS Controller" |
| when the sas qc_issue handler is run: |
| |
| BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:905 |
| in_atomic(): 0, irqs_disabled(): 1, pid: 432, name: udevd |
| CPU: 11 PID: 432 Comm: udevd Not tainted 3.14.28-rt22 #2 |
| Hardware name: Intel Corporation S2600CP/S2600CP, BIOS SE5C600.86B.02.01.0002.082220131453 08/22/2013 |
| ffff880fab500000 ffff880fa9f239c0 ffffffff81a2d273 0000000000000000 |
| ffff880fa9f239d8 ffffffff8107f023 ffff880faac23dc0 ffff880fa9f239f0 |
| ffffffff81a33cc0 ffff880faaeb1400 ffff880fa9f23a40 ffffffff815de891 |
| Call Trace: |
| [<ffffffff81a2d273>] dump_stack+0x4e/0x7a |
| [<ffffffff8107f023>] __might_sleep+0xe3/0x160 |
| [<ffffffff81a33cc0>] rt_spin_lock+0x20/0x50 |
| [<ffffffff815de891>] isci_task_execute_task+0x171/0x2f0 <----- |
| [<ffffffff815cfecb>] sas_ata_qc_issue+0x25b/0x2a0 |
| [<ffffffff81606363>] ata_qc_issue+0x1f3/0x370 |
| [<ffffffff8160c600>] ? ata_scsi_invalid_field+0x40/0x40 |
| [<ffffffff8160c8f5>] ata_scsi_translate+0xa5/0x1b0 |
| [<ffffffff8160efc6>] ata_sas_queuecmd+0x86/0x280 |
| [<ffffffff815ce446>] sas_queuecommand+0x196/0x230 |
| [<ffffffff81081fad>] ? get_parent_ip+0xd/0x50 |
| [<ffffffff815b05a4>] scsi_dispatch_cmd+0xb4/0x210 |
| [<ffffffff815b7744>] scsi_request_fn+0x314/0x530 |
| |
| and gdb shows: |
| |
| (gdb) list * isci_task_execute_task+0x171 |
| 0xffffffff815ddfb1 is in isci_task_execute_task (drivers/scsi/isci/task.c:138). |
| 133 dev_dbg(&ihost->pdev->dev, "%s: num=%d\n", __func__, num); |
| 134 |
| 135 for_each_sas_task(num, task) { |
| 136 enum sci_status status = SCI_FAILURE; |
| 137 |
| 138 spin_lock_irqsave(&ihost->scic_lock, flags); <----- |
| 139 idev = isci_lookup_device(task->dev); |
| 140 io_ready = isci_device_io_ready(idev, task); |
| 141 tag = isci_alloc_tag(ihost); |
| 142 spin_unlock_irqrestore(&ihost->scic_lock, flags); |
| (gdb) |
| |
| In addition to the scic_lock, the function also contains locking of |
| the task_state_lock -- which is clearly not a candidate for raw lock |
| conversion. As can be seen by the comment nearby, we really should |
| be running the qc_issue code with interrupts enabled anyway. |
| |
| |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
| --- |
| drivers/scsi/libsas/sas_ata.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/scsi/libsas/sas_ata.c |
| +++ b/drivers/scsi/libsas/sas_ata.c |
| @@ -190,7 +190,7 @@ static unsigned int sas_ata_qc_issue(str |
| /* TODO: audit callers to ensure they are ready for qc_issue to |
| * unconditionally re-enable interrupts |
| */ |
| - local_irq_save(flags); |
| + local_irq_save_nort(flags); |
| spin_unlock(ap->lock); |
| |
| /* If the device fell off, no sense in issuing commands */ |
| @@ -252,7 +252,7 @@ static unsigned int sas_ata_qc_issue(str |
| |
| out: |
| spin_lock(ap->lock); |
| - local_irq_restore(flags); |
| + local_irq_restore_nort(flags); |
| return ret; |
| } |
| |
