diff options
author | Christof Schmitt <christof.schmitt@de.ibm.com> | 2010-09-08 14:39:57 +0200 |
---|---|---|
committer | James Bottomley <James.Bottomley@suse.de> | 2010-09-16 22:54:19 -0400 |
commit | 44a24cb3731495336d77f3a955a7004997270dfd (patch) | |
tree | 3fdf2df31c2f528e6bd01c99a942ae2de2b9d39a /include/media | |
parent | f8210e34887e1feb977a9b6b8caa086855af40c9 (diff) |
[SCSI] zfcp: Change spin_lock_bh to spin_lock_irq to fix lockdep warning
With the change to use the data on the SCSI device, iterating through
all LUNs/scsi_devices takes the SCSI host_lock. This triggers warnings
from the lock dependency checker:
=========================================================
[ INFO: possible irq lock inversion dependency detected ]
2.6.34.1 #97
---------------------------------------------------------
chchp/3224 just changed the state of lock:
(&(shost->host_lock)->rlock){-.-...}, at: [<00000000003a73f4>] __scsi_iterate_devices+0x38/0xbc
but this lock took another, HARDIRQ-unsafe lock in the past:
(&(&qdio->req_q_lock)->rlock){+.-...}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this: [ 24.972394] 2 locks held by chchp/3224:
#0: (&(sch->lock)->rlock){-.-...}, at: [<0000000000401efa>] do_IRQ+0xb2/0x1e4
#1: (&adapter->port_list_lock){.-....}, at: [<0000000000490302>] zfcp_erp_modify_adapter_status+0x9e/0x16c
[...]
=========================================================
[ INFO: possible irq lock inversion dependency detected ]
2.6.34.1 #98
---------------------------------------------------------
chchp/3235 just changed the state of lock:
(&(shost->host_lock)->rlock){-.-...}, at: [<00000000003a73f4>] __scsi_iterate_devices+0x38/0xbc
but this lock took another, HARDIRQ-unsafe lock in the past:
(&(&qdio->stat_lock)->rlock){+.-...}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
2 locks held by chchp/3235:
#0: (&(sch->lock)->rlock){-.-...}, at: [<0000000000401efa>] do_IRQ+0xb2/0x1e4
#1: (&adapter->port_list_lock){.-.-..}, at: [<00000000004902f6>] zfcp_erp_modify_adapter_status+0x9e/0x16c
[...]
To stop this warning, change the request queue lock to disable irqs,
not only softirq. The changes are required only outside of the
critical "send fcp command" path.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Diffstat (limited to 'include/media')
0 files changed, 0 insertions, 0 deletions