hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

[SCSI] qla2xxx: fix potential deadlock on ha->hardware_lock 

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.bhat@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Jiri Kosina 2012-10-08 09:23:54 +02:00 committed by James Bottomley
parent bc977749e9
commit f24b5cb818
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/scsi/qla2xxx/qla_init.c
View File

@ -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,