From: Kevin Barnett <kevin.barnett@microsemi.com>
Date: Wed, 3 May 2017 18:52:22 -0500
Subject: scsi: smartpqi: correct remove scsi devices
Patch-mainline: v4.13-rc1
Git-commit: a37ef74517acf0d022ab4c8fa671c82c877eed7b
References: bsc#1038125

correct a problem caused by holding a spinlock during device deletion.

Reviewed-by: Scott Benesh <scott.benesh@microsemi.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>

---
 drivers/scsi/smartpqi/smartpqi_init.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index a535b26..cae979c 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -1824,19 +1824,25 @@ static void pqi_remove_all_scsi_devices(struct pqi_ctrl_info *ctrl_info)
 {
 	unsigned long flags;
 	struct pqi_scsi_dev *device;
-	struct pqi_scsi_dev *next;
 
-	spin_lock_irqsave(&ctrl_info->scsi_device_list_lock, flags);
+	while (1) {
+		spin_lock_irqsave(&ctrl_info->scsi_device_list_lock, flags);
+
+		device = list_first_entry_or_null(&ctrl_info->scsi_device_list,
+			struct pqi_scsi_dev, scsi_device_list_entry);
+		if (device)
+			list_del(&device->scsi_device_list_entry);
+
+		spin_unlock_irqrestore(&ctrl_info->scsi_device_list_lock,
+			flags);
+
+		if (!device)
+			break;
 
-	list_for_each_entry_safe(device, next, &ctrl_info->scsi_device_list,
-		scsi_device_list_entry) {
 		if (device->sdev)
 			pqi_remove_device(ctrl_info, device);
-		list_del(&device->scsi_device_list_entry);
 		pqi_free_device(device);
 	}
-
-	spin_unlock_irqrestore(&ctrl_info->scsi_device_list_lock, flags);
 }
 
 static int pqi_scan_scsi_devices(struct pqi_ctrl_info *ctrl_info)
-- 
1.8.5.6