From 0d5644b7d8daa3c1d91acb4367731f568c9c9469 Mon Sep 17 00:00:00 2001
From: Heiner Kallweit <hkallweit1@gmail.com>
Date: Wed, 3 Aug 2016 21:49:03 +0200
Subject: [PATCH] scsi: configure runtime pm before calling device_add in
 scsi_add_host_with_dma

Runtime PM should be configured already once we call device_add. See
also the description in this mail thread
https://lists.linuxfoundation.org/pipermail/linux-pm/2009-November/023198.html
or the order of calls e.g. in usb_new_device.

The changed order also helps to avoid scenarios where runtime pm for
&shost->shost_gendev is activated whilst the parent is suspended,
resulting in error message "runtime PM trying to activate child device
hostx but parent yyy is not active".

In addition properly reverse the runtime pm calls in the error path.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---
 drivers/scsi/hosts.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index ba9af4a2bd2a..9ab94adbddb7 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -246,10 +246,6 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
 
 	shost->dma_dev = dma_dev;
 
-	error = device_add(&shost->shost_gendev);
-	if (error)
-		goto out_destroy_freelist;
-
 	/*
 	 * Increase usage count temporarily here so that calling
 	 * scsi_autopm_put_host() will trigger runtime idle if there is
@@ -260,6 +256,10 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
 	pm_runtime_enable(&shost->shost_gendev);
 	device_enable_async_suspend(&shost->shost_gendev);
 
+	error = device_add(&shost->shost_gendev);
+	if (error)
+		goto out_destroy_freelist;
+
 	scsi_host_set_state(shost, SHOST_RUNNING);
 	get_device(shost->shost_gendev.parent);
 
@@ -309,6 +309,10 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
  out_del_gendev:
 	device_del(&shost->shost_gendev);
  out_destroy_freelist:
+	device_disable_async_suspend(&shost->shost_gendev);
+	pm_runtime_disable(&shost->shost_gendev);
+	pm_runtime_set_suspended(&shost->shost_gendev);
+	pm_runtime_put_noidle(&shost->shost_gendev);
 	scsi_destroy_command_freelist(shost);
  out_destroy_tags:
 	if (shost_use_blk_mq(shost))
-- 
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