libata: fix EH locking

Wrap ata_qc_complete() calls in EH context in spinlocks, to prevent
races (mainly in ATAPI code paths).

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/scsi/sata_sx4.c b/drivers/scsi/sata_sx4.c
index e2db499f22dd..a20d4285090a 100644
--- a/drivers/scsi/sata_sx4.c
+++ b/drivers/scsi/sata_sx4.c
@@ -848,10 +848,14 @@ static irqreturn_t pdc20621_interrupt (int irq, void *dev_instance, struct pt_re
 static void pdc_eng_timeout(struct ata_port *ap)
 {
         u8 drv_stat;
+        struct ata_host_set *host_set = ap->host_set;
         struct ata_queued_cmd *qc;
+        unsigned long flags;
 
         DPRINTK("ENTER\n");
 
+        spin_lock_irqsave(&host_set->lock, flags);
+
         qc = ata_qc_from_tag(ap, ap->active_tag);
         if (!qc) {
                 printk(KERN_ERR "ata%u: BUG: timeout without command\n",
@@ -885,6 +889,7 @@ static void pdc_eng_timeout(struct ata_port *ap)
         }
 
 out:
+        spin_unlock_irqrestore(&host_set->lock, flags);
         DPRINTK("EXIT\n");
 }