| Submitter | Herton Ronaldo Krzesinski |
|---|---|
| Date | Jan. 7, 2013, 8:35 p.m. |
| Message ID | <1357590955-19994-1-git-send-email-herton.krzesinski@canonical.com> |
| Download | mbox | patch |
| Permalink | /patch/210178/ |
| State | New |
| Headers | show |
Comments
Patch
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c index 6d1d873..f6f555a 100644 --- a/drivers/scsi/qla2xxx/qla_os.c +++ b/drivers/scsi/qla2xxx/qla_os.c @@ -3801,9 +3801,9 @@ qla2x00_do_dpc(void *data) "ISP abort end.\n"); } - if (test_bit(FCPORT_UPDATE_NEEDED, &base_vha->dpc_flags)) { + if (test_and_clear_bit(FCPORT_UPDATE_NEEDED, + &base_vha->dpc_flags)) { qla2x00_update_fcports(base_vha); - clear_bit(FCPORT_UPDATE_NEEDED, &base_vha->dpc_flags); } if (test_bit(SCR_PENDING, &base_vha->dpc_flags)) {
This is a note to let you know that I have just added a patch titled qla2xxx: Test and clear FCPORT_UPDATE_NEEDED atomically. to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Herton ------ From dd9cbd631d05876ee9e3fc9713c39f1a75fc7417 Mon Sep 17 00:00:00 2001 From: David Jeffery <djeffery@redhat.com> Date: Wed, 21 Nov 2012 02:39:54 -0500 Subject: [PATCH] qla2xxx: Test and clear FCPORT_UPDATE_NEEDED atomically. commit a394aac88506159e047630fc90dc2242568382d8 upstream. When the qla2xxx driver loses access to multiple, remote ports, there is a race condition which can occur which will keep the request stuck on a scsi request queue indefinitely. This bad state occurred do to a race condition with how the FCPORT_UPDATE_NEEDED bit is set in qla2x00_schedule_rport_del(), and how it is cleared in qla2x00_do_dpc(). The problem port has its drport pointer set, but it has never been processed by the driver to inform the fc transport that the port has been lost. qla2x00_schedule_rport_del() sets drport, and then sets the FCPORT_UPDATE_NEEDED bit. In qla2x00_do_dpc(), the port lists are walked and any drport pointer is handled and the fc transport informed of the port loss, then the FCPORT_UPDATE_NEEDED bit is cleared. This leaves a race where the dpc thread is processing one port removal, another port removal is marked with a call to qla2x00_schedule_rport_del(), and the dpc thread clears the bit for both removals, even though only the first removal was actually handled. Until another event occurs to set FCPORT_UPDATE_NEEDED, the later port removal is never finished and qla2xxx stays in a bad state which causes requests to become stuck on request queues. This patch updates the driver to test and clear FCPORT_UPDATE_NEEDED atomically. This ensures the port state changes are processed and not lost. Signed-off-by: David Jeffery <djeffery@redhat.com> Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com> Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> --- drivers/scsi/qla2xxx/qla_os.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 1.7.9.5