FAILED: patch "[PATCH] s390/dasd: add missing discipline function" failed to apply to 5.10-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x c0c8a8397fa8a74d04915f4d3d28cb4a5d401427
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '16782678934450@kroah.com' --subject-prefix 'PATCH 5.10.y' HEAD^..

Possible dependencies:

c0c8a8397fa8 ("s390/dasd: add missing discipline function")
4d063e646b4b ("s390/dasd: Process FCES path event notification")
b72949328869 ("s390/dasd: Prepare for additional path event handling")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From c0c8a8397fa8a74d04915f4d3d28cb4a5d401427 Mon Sep 17 00:00:00 2001
From: Stefan Haberland <sth@linux.ibm.com>
Date: Tue, 25 May 2021 14:50:06 +0200
Subject: [PATCH] s390/dasd: add missing discipline function

Fix crash with illegal operation exception in dasd_device_tasklet.
Commit b72949328869 ("s390/dasd: Prepare for additional path event handling")
renamed the verify_path function for ECKD but not for FBA and DIAG.
This leads to a panic when the path verification function is called for a
FBA or DIAG device.

Fix by defining a wrapper function for dasd_generic_verify_path().

Fixes: b72949328869 ("s390/dasd: Prepare for additional path event handling")
Cc: <stable@vger.kernel.org> #5.11
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20210525125006.157531-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c
index 1b9e1442e6a5..fd42a5fffaed 100644
--- a/drivers/s390/block/dasd_diag.c
+++ b/drivers/s390/block/dasd_diag.c
@@ -642,12 +642,18 @@ static void dasd_diag_setup_blk_queue(struct dasd_block *block)
 	blk_queue_segment_boundary(q, PAGE_SIZE - 1);
 }
 
+static int dasd_diag_pe_handler(struct dasd_device *device,
+				__u8 tbvpm, __u8 fcsecpm)
+{
+	return dasd_generic_verify_path(device, tbvpm);
+}
+
 static struct dasd_discipline dasd_diag_discipline = {
 	.owner = THIS_MODULE,
 	.name = "DIAG",
 	.ebcname = "DIAG",
 	.check_device = dasd_diag_check_device,
-	.verify_path = dasd_generic_verify_path,
+	.pe_handler = dasd_diag_pe_handler,
 	.fill_geometry = dasd_diag_fill_geometry,
 	.setup_blk_queue = dasd_diag_setup_blk_queue,
 	.start_IO = dasd_start_diag,
diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c
index 4789410885e4..3ad319aee51e 100644
--- a/drivers/s390/block/dasd_fba.c
+++ b/drivers/s390/block/dasd_fba.c
@@ -794,13 +794,19 @@ static void dasd_fba_setup_blk_queue(struct dasd_block *block)
 	blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
 }
 
+static int dasd_fba_pe_handler(struct dasd_device *device,
+			       __u8 tbvpm, __u8 fcsecpm)
+{
+	return dasd_generic_verify_path(device, tbvpm);
+}
+
 static struct dasd_discipline dasd_fba_discipline = {
 	.owner = THIS_MODULE,
 	.name = "FBA ",
 	.ebcname = "FBA ",
 	.check_device = dasd_fba_check_characteristics,
 	.do_analysis = dasd_fba_do_analysis,
-	.verify_path = dasd_generic_verify_path,
+	.pe_handler = dasd_fba_pe_handler,
 	.setup_blk_queue = dasd_fba_setup_blk_queue,
 	.fill_geometry = dasd_fba_fill_geometry,
 	.start_IO = dasd_start_IO,
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 1c59b0e86a9f..155428bfed8a 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -297,7 +297,6 @@ struct dasd_discipline {
 	 * e.g. verify that new path is compatible with the current
 	 * configuration.
 	 */
-	int (*verify_path)(struct dasd_device *, __u8);
 	int (*pe_handler)(struct dasd_device *, __u8, __u8);
 
 	/*