Commit c4a11827 authored by Matthew R. Ochs's avatar Matthew R. Ochs Committed by Martin K. Petersen
Browse files

scsi: cxlflash: Fix context reference tracking on detach 



Commit 888baf06 ("scsi: cxlflash: Add kref to context") introduced a
kref to the context. In particular, the detach routine was updated to
use the kref services for managing the removal and destruction of a
context.

As part of this change, the tracking mechanism internal to the detach
handler was refactored. This introduced a bug that can cause the
tracking state to be lost. This can lead to a situation where exclusive
access to a context is prematurely [and unknowingly] relinquished for
the executing thread.

To remedy, only update the tracking state when the kref operation
indicates the context was removed.

Fixes: 888baf06 ("scsi: cxlflash: Add kref to context")
Signed-off-by: default avatarMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: default avatarUma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent f8013261

drivers/scsi/cxlflash/superpipe.c

+2 −1
Original line number Diff line number Diff line
@@ -912,7 +912,8 @@ static int _cxlflash_disk_detach(struct scsi_device *sdev, 
	 * Release the context reference and the sdev reference that

	 * bound this LUN to the context.

	 */

	put_ctx = !kref_put(&ctxi->kref, remove_context);

	if (kref_put(&ctxi->kref, remove_context))

		put_ctx = false;

	scsi_device_put(sdev);

out:

	if (put_ctx)