Patch "scsi: cxlflash: Remove the device cleanly in the system shutdown path" has been added to the 4.8-stable tree

This is a note to let you know that I've just added the patch titled

scsi: cxlflash: Remove the device cleanly in the system shutdown path

to the 4.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
scsi-cxlflash-remove-the-device-cleanly-in-the-system-shutdown-path.patch
and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Uma Krishnan <[email protected]>
Date: Fri, 2 Sep 2016 15:39:16 -0500
Subject: scsi: cxlflash: Remove the device cleanly in the system shutdown path

From: Uma Krishnan <[email protected]>

commit babf985d1e1b0677cb264acd01319d2b9c8f4327 upstream.

Commit 704c4b0ddc03 ("cxlflash: Shutdown notify support for CXL Flash cards") was recently introduced to notify the AFU when a system is going down. Due to the position of the cxlflash driver in the device stack, cxlflash devices are _always_ removed during a reboot/shutdown. This can lead to a crash if the cxlflash shutdown hook is invoked _after_ the shutdown hook for the owning virtual PHB. Furthermore, the current implementation of shutdown/remove hooks for cxlflash are not tolerant to being invoked when the device is not enabled. This can also lead to a crash in situations where the remove hook is invoked after the device has been removed via the vPHBs shutdown hook. An example of this scenario would be an EEH reset failure while a reboot/shutdown is in progress.

To solve both problems, the shutdown hook for cxlflash is updated to simply remove the device. This path already includes the AFU notification and thus this solution will continue to perform the original intent. At the same time, the remove hook is updated to protect against being called when the device is not enabled.

cards")

---
 drivers/scsi/cxlflash/main.c |   18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

@@ -823,17 +823,6 @@ static void notify_shutdown(struct cxlfl
 }
 
 /**
- * cxlflash_shutdown() - shutdown handler
- * @pdev:	PCI device associated with the host.
- */
-static void cxlflash_shutdown(struct pci_dev *pdev)
-{
-	struct cxlflash_cfg *cfg = pci_get_drvdata(pdev);
-
-	notify_shutdown(cfg, false);
-}
-
-/**
  * cxlflash_remove() - PCI entry point to tear down host
  * @pdev:	PCI device associated with the host.
  *

@@ -844,6 +833,11 @@ static void cxlflash_remove(struct pci_d
 	struct cxlflash_cfg *cfg = pci_get_drvdata(pdev);
 	ulong lock_flags;
 
+	if (!pci_is_enabled(pdev)) {
+		pr_debug("%s: Device is disabled\n", __func__);
+		return;
+	}
+
 	/* If a Task Management Function is active, wait for it to complete
 	 * before continuing with remove.
 	 */

@@ -2685,7 +2679,7 @@ static struct pci_driver cxlflash_driver
 	.id_table = cxlflash_pci_table,
 	.probe = cxlflash_probe,
 	.remove = cxlflash_remove,
-	.shutdown = cxlflash_shutdown,
+	.shutdown = cxlflash_remove,
 	.err_handler = &cxlflash_err_handler,
 };
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.8/scsi-cxlflash-remove-the-device-cleanly-in-the-system-shutdown-path.patch