Commit d4422774 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by James Bottomley
Browse files

scsi_dh: don't allow to detach device handlers at runtime 



The I/O submission and completion paths call into the device handler
without any synchronization agains detachment.  So disallow detaching
device handlers at runtime.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
parent e959ed9a

drivers/scsi/scsi_dh.c

+4 −2
Original line number Diff line number Diff line
@@ -181,8 +181,10 @@ store_dh_state(struct device *dev, struct device_attribute *attr, 
			/*

			 * Detach from a device handler

			 */

			scsi_dh_handler_detach(sdev);

			err = 0;

			sdev_printk(KERN_WARNING, sdev,

				    "can't detach handler %s.\n",

				    sdev->handler->name);

			err = -EINVAL;

		} else if (!strncmp(buf, "activate", 8)) {

			/*

			 * Activate a device handler