From: James Smart <jsmart2021@gmail.com>
Date: Mon, 10 Sep 2018 10:30:46 -0700
Subject: [PATCH] scsi: lpfc: Correct irq handling via locks when taking
adapter offline
Git-commit: 523128e53b1e82a7eb422168eddd0c566973520d
Patch-mainline: v4.20-rc1
References: bsc#1114015
When taking the board offline while performing i/o, unsafe locking errors
occurred and irq level isn't properly managed.
In lpfc_sli_hba_down, spin_lock_irqsave(&phba->hbalock, flags) does not
disable softirqs raised from timer expiry. It is possible that a softirq is
raised from the lpfc_els_retry_delay routine and recursively requests the same
phba->hbalock spinlock causing deadlock.
Address the deadlocks by creating a new port_list lock. The softirq behavior
can then be managed a level deeper into the calling sequences.
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/lpfc/lpfc.h | 1 +
drivers/scsi/lpfc/lpfc_ct.c | 6 +++---
drivers/scsi/lpfc/lpfc_els.c | 3 +++
drivers/scsi/lpfc/lpfc_hbadisc.c | 6 +++---
drivers/scsi/lpfc/lpfc_init.c | 19 +++++++++++--------
drivers/scsi/lpfc/lpfc_sli.c | 25 ++++++++++++++++++++++++-
drivers/scsi/lpfc/lpfc_vport.c | 14 +++++++-------
7 files changed, 52 insertions(+), 22 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc.h b/drivers/scsi/lpfc/lpfc.h
index 6993debe4239..6340883ece33 100644
--- a/drivers/scsi/lpfc/lpfc.h
+++ b/drivers/scsi/lpfc/lpfc.h
@@ -964,6 +964,7 @@ struct lpfc_hba {
uint32_t intr_mode;
#define LPFC_INTR_ERROR 0xFFFFFFFF
struct list_head port_list;
+ spinlock_t port_list_lock; /* lock for port_list mutations */
struct lpfc_vport *pport; /* physical lpfc_vport pointer */
uint16_t max_vpi; /* Maximum virtual nports */
#define LPFC_MAX_VPI 0xFFFF /* Max number of VPI supported */
diff --git a/drivers/scsi/lpfc/lpfc_ct.c b/drivers/scsi/lpfc/lpfc_ct.c
index 0eae8051e920..789ad1502534 100644
--- a/drivers/scsi/lpfc/lpfc_ct.c
+++ b/drivers/scsi/lpfc/lpfc_ct.c
@@ -445,14 +445,14 @@ lpfc_find_vport_by_did(struct lpfc_hba *phba, uint32_t did) {
struct lpfc_vport *vport_curr;
unsigned long flags;
- spin_lock_irqsave(&phba->hbalock, flags);
+ spin_lock_irqsave(&phba->port_list_lock, flags);
list_for_each_entry(vport_curr, &phba->port_list, listentry) {
if ((vport_curr->fc_myDID) && (vport_curr->fc_myDID == did)) {
- spin_unlock_irqrestore(&phba->hbalock, flags);
+ spin_unlock_irqrestore(&phba->port_list_lock, flags);
return vport_curr;
}
}
- spin_unlock_irqrestore(&phba->hbalock, flags);
+ spin_unlock_irqrestore(&phba->port_list_lock, flags);
return NULL;
}
diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index 4dda969e947c..f1c1faa74b46 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -7673,8 +7673,11 @@ void
lpfc_els_flush_all_cmd(struct lpfc_hba *phba)
{
struct lpfc_vport *vport;
+
+ spin_lock_irq(&phba->port_list_lock);
list_for_each_entry(vport, &phba->port_list, listentry)
lpfc_els_flush_cmd(vport);
+ spin_unlock_irq(&phba->port_list_lock);
return;
}
diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 235abd50e530..f9a038ec5256 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -5938,14 +5938,14 @@ lpfc_find_vport_by_vpid(struct lpfc_hba *phba, uint16_t vpi)
}
}
- spin_lock_irqsave(&phba->hbalock, flags);
+ spin_lock_irqsave(&phba->port_list_lock, flags);
list_for_each_entry(vport, &phba->port_list, listentry) {
if (vport->vpi == i) {
- spin_unlock_irqrestore(&phba->hbalock, flags);
+ spin_unlock_irqrestore(&phba->port_list_lock, flags);
return vport;
}
}
- spin_unlock_irqrestore(&phba->hbalock, flags);
+ spin_unlock_irqrestore(&phba->port_list_lock, flags);
return NULL;
}
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 90fb83f88179..bb2bff7b56b4 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -3988,9 +3988,9 @@ lpfc_create_port(struct lpfc_hba *phba, int instance, struct device *dev)
if (error)
goto out_put_shost;
- spin_lock_irq(&phba->hbalock);
+ spin_lock_irq(&phba->port_list_lock);
list_add_tail(&vport->listentry, &phba->port_list);
- spin_unlock_irq(&phba->hbalock);
+ spin_unlock_irq(&phba->port_list_lock);
return vport;
out_put_shost:
@@ -4016,9 +4016,9 @@ destroy_port(struct lpfc_vport *vport)
fc_remove_host(shost);
scsi_remove_host(shost);
- spin_lock_irq(&phba->hbalock);
+ spin_lock_irq(&phba->port_list_lock);
list_del_init(&vport->listentry);
- spin_unlock_irq(&phba->hbalock);
+ spin_unlock_irq(&phba->port_list_lock);
lpfc_cleanup(vport);
return;
@@ -5621,7 +5621,10 @@ lpfc_setup_driver_resource_phase1(struct lpfc_hba *phba)
/* Initialize ndlp management spinlock */
spin_lock_init(&phba->ndlp_lock);
+ /* Initialize port_list spinlock */
+ spin_lock_init(&phba->port_list_lock);
INIT_LIST_HEAD(&phba->port_list);
+
INIT_LIST_HEAD(&phba->work_list);
init_waitqueue_head(&phba->wait_4_mlo_m_q);
@@ -10985,9 +10988,9 @@ lpfc_pci_remove_one_s3(struct pci_dev *pdev)
kfree(phba->vpi_ids);
lpfc_stop_hba_timers(phba);
- spin_lock_irq(&phba->hbalock);
+ spin_lock_irq(&phba->port_list_lock);
list_del_init(&vport->listentry);
- spin_unlock_irq(&phba->hbalock);
+ spin_unlock_irq(&phba->port_list_lock);
lpfc_debugfs_terminate(vport);
@@ -11797,9 +11800,9 @@ lpfc_pci_remove_one_s4(struct pci_dev *pdev)
lpfc_sli4_hba_unset(phba);
lpfc_stop_hba_timers(phba);
- spin_lock_irq(&phba->hbalock);
+ spin_lock_irq(&phba->port_list_lock);
list_del_init(&vport->listentry);
- spin_unlock_irq(&phba->hbalock);
+ spin_unlock_irq(&phba->port_list_lock);
/* Perform scsi free before driver resource_unset since scsi
* buffers are released to their corresponding pools here.
diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index a95c823cd1a4..495de99ed82d 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -10273,8 +10273,12 @@ lpfc_sli_mbox_sys_flush(struct lpfc_hba *phba)
LPFC_MBOXQ_t *pmb;
unsigned long iflag;
+ /* Disable softirqs, including timers from obtaining phba->hbalock */
+ local_bh_disable();
+
/* Flush all the mailbox commands in the mbox system */
spin_lock_irqsave(&phba->hbalock, iflag);
+
/* The pending mailbox command queue */
list_splice_init(&phba->sli.mboxq, &completions);
/* The outstanding active mailbox command */
@@ -10287,6 +10291,9 @@ lpfc_sli_mbox_sys_flush(struct lpfc_hba *phba)
list_splice_init(&phba->sli.mboxq_cmpl, &completions);
spin_unlock_irqrestore(&phba->hbalock, iflag);
+ /* Enable softirqs again, done with phba->hbalock */
+ local_bh_enable();
+
/* Return all flushed mailbox commands with MBX_NOT_FINISHED status */
while (!list_empty(&completions)) {
list_remove_head(&completions, pmb, LPFC_MBOXQ_t, list);
@@ -10426,6 +10433,9 @@ lpfc_sli_hba_down(struct lpfc_hba *phba)
lpfc_hba_down_prep(phba);
+ /* Disable softirqs, including timers from obtaining phba->hbalock */
+ local_bh_disable();
+
lpfc_fabric_abort_hba(phba);
spin_lock_irqsave(&phba->hbalock, flags);
@@ -10479,6 +10489,9 @@ lpfc_sli_hba_down(struct lpfc_hba *phba)
kfree(buf_ptr);
}
+ /* Enable softirqs again, done with phba->hbalock */
+ local_bh_enable();
+
/* Return any active mbox cmds */
del_timer_sync(&psli->mbox_tmo);
@@ -11782,6 +11795,9 @@ lpfc_sli_mbox_sys_shutdown(struct lpfc_hba *phba, int mbx_action)
}
timeout = msecs_to_jiffies(LPFC_MBOX_TMO * 1000) + jiffies;
+ /* Disable softirqs, including timers from obtaining phba->hbalock */
+ local_bh_disable();
+
spin_lock_irq(&phba->hbalock);
psli->sli_flag |= LPFC_SLI_ASYNC_MBX_BLK;
@@ -11795,6 +11811,9 @@ lpfc_sli_mbox_sys_shutdown(struct lpfc_hba *phba, int mbx_action)
1000) + jiffies;
spin_unlock_irq(&phba->hbalock);
+ /* Enable softirqs again, done with phba->hbalock */
+ local_bh_enable();
+
while (phba->sli.mbox_active) {
/* Check active mailbox complete status every 2ms */
msleep(2);
@@ -11804,9 +11823,13 @@ lpfc_sli_mbox_sys_shutdown(struct lpfc_hba *phba, int mbx_action)
*/
break;
}
- } else
+ } else {
spin_unlock_irq(&phba->hbalock);
+ /* Enable softirqs again, done with phba->hbalock */
+ local_bh_enable();
+ }
+
lpfc_sli_mbox_sys_flush(phba);
}
diff --git a/drivers/scsi/lpfc/lpfc_vport.c b/drivers/scsi/lpfc/lpfc_vport.c
index 1ff0f7de9105..c340e0e47473 100644
--- a/drivers/scsi/lpfc/lpfc_vport.c
+++ b/drivers/scsi/lpfc/lpfc_vport.c
@@ -207,7 +207,7 @@ lpfc_unique_wwpn(struct lpfc_hba *phba, struct lpfc_vport *new_vport)
struct lpfc_vport *vport;
unsigned long flags;
- spin_lock_irqsave(&phba->hbalock, flags);
+ spin_lock_irqsave(&phba->port_list_lock, flags);
list_for_each_entry(vport, &phba->port_list, listentry) {
if (vport == new_vport)
continue;
@@ -215,11 +215,11 @@ lpfc_unique_wwpn(struct lpfc_hba *phba, struct lpfc_vport *new_vport)
if (memcmp(&vport->fc_sparam.portName,
&new_vport->fc_sparam.portName,
sizeof(struct lpfc_name)) == 0) {
- spin_unlock_irqrestore(&phba->hbalock, flags);
+ spin_unlock_irqrestore(&phba->port_list_lock, flags);
return 0;
}
}
- spin_unlock_irqrestore(&phba->hbalock, flags);
+ spin_unlock_irqrestore(&phba->port_list_lock, flags);
return 1;
}
@@ -825,9 +825,9 @@ lpfc_vport_delete(struct fc_vport *fc_vport)
lpfc_free_vpi(phba, vport->vpi);
vport->work_port_events = 0;
- spin_lock_irq(&phba->hbalock);
+ spin_lock_irq(&phba->port_list_lock);
list_del_init(&vport->listentry);
- spin_unlock_irq(&phba->hbalock);
+ spin_unlock_irq(&phba->port_list_lock);
lpfc_printf_vlog(vport, KERN_ERR, LOG_VPORT,
"1828 Vport Deleted.\n");
scsi_host_put(shost);
@@ -844,7 +844,7 @@ lpfc_create_vport_work_array(struct lpfc_hba *phba)
GFP_KERNEL);
if (vports == NULL)
return NULL;
- spin_lock_irq(&phba->hbalock);
+ spin_lock_irq(&phba->port_list_lock);
list_for_each_entry(port_iterator, &phba->port_list, listentry) {
if (port_iterator->load_flag & FC_UNLOADING)
continue;
@@ -856,7 +856,7 @@ lpfc_create_vport_work_array(struct lpfc_hba *phba)
}
vports[index++] = port_iterator;
}
- spin_unlock_irq(&phba->hbalock);
+ spin_unlock_irq(&phba->port_list_lock);
return vports;
}
--
2.16.4