From: Martin Wilck <mwilck@suse.com>
Date: Thu, 27 Jan 2022 15:13:51 +0100
Subject: [PATCH] scsi: core: Make "access_state" sysfs attribute always
 visible
Git-commit: 7cddf7e8d1e88603d0e86997259fdec98da6f70a
Patch-mainline: v5.18-rc1
References: jsc#PED-1559

If a SCSI device handler module is loaded after some SCSI devices have
already been probed (e.g. via request_module() by dm-multipath), the
"access_state" and "preferred_path" sysfs attributes remain invisible for
these devices, although the handler is attached and live. The reason is
that the visibility is only checked when the sysfs attribute group is first
created. This results in an inconsistent user experience depending on the
load order of SCSI low-level drivers vs. device handler modules.

This patch changes user space API: attempting to read the "access_state" or
"preferred_path" attributes will now result in -EINVAL rather than -ENODEV
for devices that have no device handler, and tests for the existence of
these attributes will have a different result.

Link: https://lore.kernel.org/r/20220127141351.30706-1-mwilck@suse.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/scsi/scsi_sysfs.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index f1e0c131b77c..226a50944c00 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -1228,14 +1228,6 @@ static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj,
 	    !sdev->host->hostt->change_queue_depth)
 		return 0;
 
-#ifdef CONFIG_SCSI_DH
-	if (attr == &dev_attr_access_state.attr &&
-	    !sdev->handler)
-		return 0;
-	if (attr == &dev_attr_preferred_path.attr &&
-	    !sdev->handler)
-		return 0;
-#endif
 	return attr->mode;
 }
 
-- 
2.35.3