[PATCH v2 2/2] scsi: arcmsr: Confirm getting a free ccb is in spin_lock circle

From: ching Huang
Date: Mon Oct 26 2020 - 23:39:17 EST


From: ching Huang <ching2048@xxxxxxxxxxxx>

Confirm getting a free ccb is in spin_lock circle.

Signed-off-by: ching Huang <ching2048@xxxxxxxxxxxx>
---

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 7cfae1d..127fe50 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -3162,10 +3162,12 @@ message_out:

static struct CommandControlBlock *arcmsr_get_freeccb(struct AdapterControlBlock *acb)
{
- struct list_head *head = &acb->ccb_free_list;
+ struct list_head *head;
struct CommandControlBlock *ccb = NULL;
unsigned long flags;
+
spin_lock_irqsave(&acb->ccblist_lock, flags);
+ head = &acb->ccb_free_list;
if (!list_empty(head)) {
ccb = list_entry(head->next, struct CommandControlBlock, list);
list_del_init(&ccb->list);