[SCSI] BNX2FC: hung task timeout warning observed when rmmod bnx2x with active FCoE targets
[v2] - removed the interface->enabled flag setting which prevented the
fcoe ctlr link from being brought back up after a MTU change
A rtnl_lock deadlock was observed from the rmmod thread where it
tries to unregister the fcoe_ctlr device. This unregistration
triggered a flush of the sysfs queue of the associated ctlr and led to
a call to the set_fcoe_ctlr_enabled routine. This will eventually propagate
down to call the bnx2fc_disable routine and contented for the rtnl_lock
in the same context.
This patch creates a subset of the bnx2fc_enable/disable routine which
removes the unnecesary rtnl_lock and the bnx2fc_dev_lock acquisition from
the set_fcoe_ctlr_enabled path.
kernel: INFO: task rmmod:7874 blocked for more than 120 seconds.
kernel: Tainted: G W --------------- 2.6.32-415.0.1.el6.x86_64 #1
kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kernel: rmmod D 000000000000000f 0 7874 6518 0x00000080
kernel: ffff88022158f7d8 0000000000000086 0000000000000000 0000000000000000
kernel: ffff88023fe72600 ffff88043c74d410 ffff88043c74d400 ffff88043c74d000
kernel: ffff88021ecbe5f8 ffff88022158ffd8 000000000000fbc8 ffff88021ecbe5f8
kernel: Call Trace:
kernel: [<ffffffff81525985>] schedule_timeout+0x215/0x2e0
kernel: [<ffffffff810680c0>] ? pick_next_task_fair+0xd0/0x130
kernel: [<ffffffff81524858>] ? schedule+0x178/0x3b2
kernel: [<ffffffff81525603>] wait_for_common+0x123/0x180
kernel: [<ffffffff81066b40>] ? default_wake_function+0x0/0x20
kernel: [<ffffffff811a486e>] ? ifind_fast+0x5e/0xb0
kernel: [<ffffffff8152571d>] wait_for_completion+0x1d/0x20
kernel: [<ffffffff81203868>] sysfs_addrm_finish+0x228/0x270
kernel: [<ffffffff812014ab>] sysfs_hash_and_remove+0x5b/0x90
kernel: [<ffffffff812056af>] sysfs_remove_group+0x5f/0x100
kernel: [<ffffffff81367e8b>] device_remove_groups+0x3b/0x60
kernel: [<ffffffff8136811d>] device_remove_attrs+0x3d/0x90
kernel: [<ffffffff81368295>] device_del+0x125/0x1e0
kernel: [<ffffffff81368372>] device_unregister+0x22/0x60
kernel: [<ffffffffa038ead2>] fcoe_ctlr_device_delete+0xe2/0xf4 [libfcoe]
kernel: [<ffffffffa03c43cb>] bnx2fc_interface_release+0x5b/0x90 [bnx2fc]
kernel: [<ffffffffa03c4370>] ? bnx2fc_interface_release+0x0/0x90 [bnx2fc]
kernel: [<ffffffff812835e7>] kref_put+0x37/0x70
kernel: [<ffffffffa03c4192>] __bnx2fc_destroy+0x72/0xa0 [bnx2fc]
kernel: [<ffffffffa03c5265>] bnx2fc_ulp_exit+0xf5/0x160 [bnx2fc] <- got bnx2fc_dev_lock mutex_lock
kernel: [<ffffffffa03b03c6>] cnic_ulp_exit+0xb6/0xc0 [cnic]
kernel: [<ffffffffa03b5418>] cnic_netdev_event+0x368/0x370 [cnic]
kernel: [<ffffffffa038c56c>] ? fcoe_del_netdev_mapping+0x8c/0xa0 [libfcoe]
kernel: [<ffffffff8152a6e5>] notifier_call_chain+0x55/0x80
kernel: [<ffffffff810a0a46>] raw_notifier_call_chain+0x16/0x20
kernel: [<ffffffff81459beb>] call_netdevice_notifiers+0x1b/0x20
kernel: [<ffffffff8145ab34>] rollback_registered_many+0x154/0x280
kernel: [<ffffffff8145ad08>] rollback_registered+0x38/0x50
kernel: [<ffffffff8145ad78>] unregister_netdevice_queue+0x58/0xa0
kernel: [<ffffffff8145add0>] unregister_netdevice+0x10/0x20
kernel: [<ffffffff8145adfe>] unregister_netdev+0x1e/0x30 <- got rtnl_lock!!!!!!!!!
kernel: [<ffffffffa0122278>] __bnx2x_remove+0x48/0x270 [bnx2x] <- got & rel rtnl_lock
kernel: [<ffffffffa0122554>] bnx2x_remove_one+0x44/0x80 [bnx2x]
kernel: [<ffffffff812a3af7>] pci_device_remove+0x37/0x70
kernel: [<ffffffff8136b2ef>] __device_release_driver+0x6f/0xe0
kernel: [<ffffffff8136b428>] driver_detach+0xc8/0xd0
kernel: [<ffffffff8136a22e>] bus_remove_driver+0x8e/0x110
kernel: [<ffffffff8136bc12>] driver_unregister+0x62/0xa0
kernel: [<ffffffff812a3e04>] pci_unregister_driver+0x44/0xb0
kernel: [<ffffffffa0191954>] bnx2x_cleanup+0x18/0x73 [bnx2x]
kernel: [<ffffffff810b8be4>] sys_delete_module+0x194/0x260
kernel: [<ffffffff810e1347>] ? audit_syscall_entry+0x1d7/0x200
kernel: [<ffffffff8100b072>] system_call_fastpath+0x16/0x1b
Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
index 69ac554..7a25766 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
@@ -2004,6 +2004,24 @@
set_bit(BNX2FC_CNIC_REGISTERED, &hba->reg_with_cnic);
}
+/* Assumes rtnl_lock and the bnx2fc_dev_lock are already taken */
+static int __bnx2fc_disable(struct fcoe_ctlr *ctlr)
+{
+ struct bnx2fc_interface *interface = fcoe_ctlr_priv(ctlr);
+
+ if (interface->enabled == true) {
+ if (!ctlr->lp) {
+ pr_err(PFX "__bnx2fc_disable: lport not found\n");
+ return -ENODEV;
+ } else {
+ interface->enabled = false;
+ fcoe_ctlr_link_down(ctlr);
+ fcoe_clean_pending_queue(ctlr->lp);
+ }
+ }
+ return 0;
+}
+
/**
* Deperecated: Use bnx2fc_enabled()
*/
@@ -2018,20 +2036,34 @@
interface = bnx2fc_interface_lookup(netdev);
ctlr = bnx2fc_to_ctlr(interface);
- if (!interface || !ctlr->lp) {
- rc = -ENODEV;
- printk(KERN_ERR PFX "bnx2fc_disable: interface or lport not found\n");
- } else {
- interface->enabled = false;
- fcoe_ctlr_link_down(ctlr);
- fcoe_clean_pending_queue(ctlr->lp);
- }
+ if (!interface) {
+ rc = -ENODEV;
+ pr_err(PFX "bnx2fc_disable: interface not found\n");
+ } else {
+ rc = __bnx2fc_disable(ctlr);
+ }
mutex_unlock(&bnx2fc_dev_lock);
rtnl_unlock();
return rc;
}
+static int __bnx2fc_enable(struct fcoe_ctlr *ctlr)
+{
+ struct bnx2fc_interface *interface = fcoe_ctlr_priv(ctlr);
+
+ if (interface->enabled == false) {
+ if (!ctlr->lp) {
+ pr_err(PFX "__bnx2fc_enable: lport not found\n");
+ return -ENODEV;
+ } else if (!bnx2fc_link_ok(ctlr->lp)) {
+ fcoe_ctlr_link_up(ctlr);
+ interface->enabled = true;
+ }
+ }
+ return 0;
+}
+
/**
* Deprecated: Use bnx2fc_enabled()
*/
@@ -2046,12 +2078,11 @@
interface = bnx2fc_interface_lookup(netdev);
ctlr = bnx2fc_to_ctlr(interface);
- if (!interface || !ctlr->lp) {
+ if (!interface) {
rc = -ENODEV;
- printk(KERN_ERR PFX "bnx2fc_enable: interface or lport not found\n");
- } else if (!bnx2fc_link_ok(ctlr->lp)) {
- fcoe_ctlr_link_up(ctlr);
- interface->enabled = true;
+ pr_err(PFX "bnx2fc_enable: interface not found\n");
+ } else {
+ rc = __bnx2fc_enable(ctlr);
}
mutex_unlock(&bnx2fc_dev_lock);
@@ -2072,14 +2103,12 @@
static int bnx2fc_ctlr_enabled(struct fcoe_ctlr_device *cdev)
{
struct fcoe_ctlr *ctlr = fcoe_ctlr_device_priv(cdev);
- struct fc_lport *lport = ctlr->lp;
- struct net_device *netdev = bnx2fc_netdev(lport);
switch (cdev->enabled) {
case FCOE_CTLR_ENABLED:
- return bnx2fc_enable(netdev);
+ return __bnx2fc_enable(ctlr);
case FCOE_CTLR_DISABLED:
- return bnx2fc_disable(netdev);
+ return __bnx2fc_disable(ctlr);
case FCOE_CTLR_UNUSED:
default:
return -ENOTSUPP;
