Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiHEADmaster

Pull SCSI fixes from James Bottomley:
 "Two minor core fixes: one for power management issues in error
  handling and the other to fix a deadlock in door locking of SCSI
  devices with removable media; and a minor bug fix for the debug
  driver"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: scsi_debug: Negate wrapped memcmp() result
  scsi: core: Do not block on tag allocation in scsi_eh_lock_door()
  scsi: core: pair EH runtime PM get and put

4 files changed, 12 insertions, 10 deletions

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 643051332132..4fb2dc403962 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -4310,8 +4310,8 @@ static bool comp_write_worker(struct sdeb_store_info *sip, u64 lba, u32 num,
 	if (!res)
 		return res;
 	if (rest)
-		res = memcmp(fsp, arr + ((num - rest) * lb_size),
-			     rest * lb_size);
+		res = !memcmp(fsp, arr + ((num - rest) * lb_size),
+			      rest * lb_size);
 	if (!res)
 		return res;
 	if (compare_only)
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 453a2232452d..b729407348f7 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -2161,7 +2161,7 @@ static void scsi_eh_lock_door(struct scsi_device *sdev)
 	struct scsi_cmnd *scmd;
 	struct request *req;
 
-	req = scsi_alloc_request(sdev->request_queue, REQ_OP_DRV_IN, 0);
+	req = scsi_alloc_request(sdev->request_queue, REQ_OP_DRV_IN, BLK_MQ_REQ_NOWAIT);
 	if (IS_ERR(req))
 		return;
 	scmd = blk_mq_rq_to_pdu(req);
@@ -2362,6 +2362,7 @@ static void scsi_unjam_host(struct Scsi_Host *shost)
 int scsi_error_handler(void *data)
 {
 	struct Scsi_Host *shost = data;
+	bool eh_noresume;
 
 	/*
 	 * We use TASK_INTERRUPTIBLE so that the thread is not
@@ -2403,7 +2404,8 @@ int scsi_error_handler(void *data)
 		 * what we need to do to get it up and online again (if we can).
 		 * If we fail, we end up taking the thing offline.
 		 */
-		if (!shost->eh_noresume && scsi_autopm_get_host(shost) != 0) {
+		eh_noresume = READ_ONCE(shost->eh_noresume);
+		if (!eh_noresume && scsi_autopm_get_host(shost) != 0) {
 			SCSI_LOG_ERROR_RECOVERY(1,
 				shost_printk(KERN_ERR, shost,
 					     "scsi_eh_%d: unable to autoresume\n",
@@ -2427,7 +2429,7 @@ int scsi_error_handler(void *data)
 		 * which are still online.
 		 */
 		scsi_restart_operations(shost);
-		if (!shost->eh_noresume)
+		if (!eh_noresume)
 			scsi_autopm_put_host(shost);
 	}
 	__set_current_state(TASK_RUNNING);
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 13e6357a8bbb..a41b56dbf3b7 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -10016,7 +10016,7 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
 	 * we are functional while we are here, skip host resume in error
 	 * handling context.
 	 */
-	hba->host->eh_noresume = 1;
+	WRITE_ONCE(hba->host->eh_noresume, 1);
 
 	/*
 	 * Current function would be generally called from the power management
@@ -10038,7 +10038,7 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
 	}
 
 	scsi_device_put(sdp);
-	hba->host->eh_noresume = 0;
+	WRITE_ONCE(hba->host->eh_noresume, 0);
 	return ret;
 }
 
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index f6b286fa59f2..98b0ccf0813e 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -664,6 +664,9 @@ struct Scsi_Host {
 	/* Asynchronous scan in progress */
 	bool async_scan __guarded_by(&scan_mutex);
 
+	/* Don't resume host in EH */
+	bool eh_noresume;
+
 	unsigned active_mode:2;
 
 	/*
@@ -682,9 +685,6 @@ struct Scsi_Host {
 	/* Task mgmt function in progress */
 	unsigned tmf_in_progress:1;
 
-	/* Don't resume host in EH */
-	unsigned eh_noresume:1;
-
 	/* The controller does not support WRITE SAME */
 	unsigned no_write_same:1;