scsi: core: Move scsi_host_busy() out of host lock if it is for per-command

Commit 4373534a9850 ("scsi: core: Move scsi_host_busy() out of host lock
for waking up EH handler") intended to fix a hard lockup issue triggered by
EH. The core idea was to move scsi_host_busy() out of the host lock when
processing individual commands for EH. However, a suggested style change
inadvertently caused scsi_host_busy() to remain under the host lock. Fix
this by calling scsi_host_busy() outside the lock.

Fixes: 4373534a9850 ("scsi: core: Move scsi_host_busy() out of host lock for waking up EH handler")
Cc: Sathya Prakash Veerichetty <safhya.prakash@broadcom.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20240203024521.2006455-1-ming.lei@redhat.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 4f455884fdc440188124d845ef0535f4da418d22..612489afe8d2467965759c80562562e26919f704 100644 (file)
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -282,11 +282,12 @@ static void scsi_eh_inc_host_failed(struct rcu_head *head)
 {
        struct scsi_cmnd *scmd = container_of(head, typeof(*scmd), rcu);
        struct Scsi_Host *shost = scmd->device->host;
+       unsigned int busy = scsi_host_busy(shost);
        unsigned long flags;
 
        spin_lock_irqsave(shost->host_lock, flags);
        shost->host_failed++;
-       scsi_eh_wakeup(shost, scsi_host_busy(shost));
+       scsi_eh_wakeup(shost, busy);
        spin_unlock_irqrestore(shost->host_lock, flags);
 }
 

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 1fb80eae9a63a30787dee6583e2a0cfe5c96f0ce..df5ac03d5d6c2eb5233ad7fcfdad37a1e487b4e6 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -278,9 +278,11 @@ static void scsi_dec_host_busy(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
        rcu_read_lock();
        __clear_bit(SCMD_STATE_INFLIGHT, &cmd->state);
        if (unlikely(scsi_host_in_recovery(shost))) {
+               unsigned int busy = scsi_host_busy(shost);
+
                spin_lock_irqsave(shost->host_lock, flags);
                if (shost->host_failed || shost->host_eh_scheduled)
-                       scsi_eh_wakeup(shost, scsi_host_busy(shost));
+                       scsi_eh_wakeup(shost, busy);
                spin_unlock_irqrestore(shost->host_lock, flags);
        }
        rcu_read_unlock();