Lockdep reports:
=== [ cut here ] ===
=========================================================
[ INFO: possible irq lock inversion dependency detected ]
3.6.0-0.0.0.28.36b5ec9-default #1 Not tainted
---------------------------------------------------------
qla2xxx_1_dpc/368 just changed the state of lock:
(&(&ha->vport_slock)->rlock){+.....}, at: [<ffffffffa009b377>]
qla2x00_configure_hba+0x197/0x3c0 [qla2xxx]
but this lock was taken by another, HARDIRQ-safe lock in the past:
(&(&ha->hardware_lock)->rlock){-.....}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&(&ha->vport_slock)->rlock);
local_irq_disable();
lock(&(&ha->hardware_lock)->rlock);
lock(&(&ha->vport_slock)->rlock);
<Interrupt>
lock(&(&ha->hardware_lock)->rlock);
=== [ cut here ] ===
Fix the potential deadlock by disabling IRQs while holding ha->vport_slock.
Reported-and-tested-by: Srivatsa S. Bhat <srivatsa.b...@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkos...@suse.cz>
---
drivers/scsi/qla2xxx/qla_init.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 799a58b..48fca47 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -2080,6 +2080,7 @@ qla2x00_configure_hba(scsi_qla_host_t *vha)
uint8_t domain;
char connect_type[22];
struct qla_hw_data *ha = vha->hw;
+ unsigned long flags;
/* Get host addresses. */
rval = qla2x00_get_adapter_id(vha,
@@ -2154,9 +2155,9 @@ qla2x00_configure_hba(scsi_qla_host_t *vha)
vha->d_id.b.area = area;
vha->d_id.b.al_pa = al_pa;
- spin_lock(&ha->vport_slock);
+ spin_lock_irqsave(&ha->vport_slock, flags);
qlt_update_vp_map(vha, SET_AL_PA);
- spin_unlock(&ha->vport_slock);
+ spin_unlock_irqrestore(&ha->vport_slock, flags);
if (!vha->flags.init_done)
ql_log(ql_log_info, vha, 0x2010,
--
Jiri Kosina
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
