+ dm-cleanup-alloc_dax-error-handling.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: dm: cleanup alloc_dax() error handling
has been added to the -mm mm-unstable branch.  Its filename is
     dm-cleanup-alloc_dax-error-handling.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/dm-cleanup-alloc_dax-error-handling.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: dm: cleanup alloc_dax() error handling
Date: Thu, 8 Feb 2024 13:49:11 -0500

Now that alloc_dax() returns ERR_PTR(-EOPNOTSUPP) rather than NULL, the
callers do not have to handle NULL return values anymore.

Link: https://lkml.kernel.org/r/20240208184913.484340-11-mathieu.desnoyers@efficios.com
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/md/dm.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/md/dm.c~dm-cleanup-alloc_dax-error-handling
+++ a/drivers/md/dm.c
@@ -2124,8 +2124,8 @@ static struct mapped_device *alloc_dev(i
 	sprintf(md->disk->disk_name, "dm-%d", minor);
 
 	dax_dev = alloc_dax(md, &dm_dax_ops);
-	if (IS_ERR_OR_NULL(dax_dev)) {
-		if (IS_ERR(dax_dev) && PTR_ERR(dax_dev) != -EOPNOTSUPP)
+	if (IS_ERR(dax_dev)) {
+		if (PTR_ERR(dax_dev) != -EOPNOTSUPP)
 			goto bad;
 	} else {
 		set_dax_nocache(dax_dev);
_

Patches currently in -mm which might be from mathieu.desnoyers@efficios.com are

nvdimm-pmem-fix-leak-on-dax_add_host-failure.patch
nvdimm-pmem-treat-alloc_dax-eopnotsupp-failure-as-non-fatal.patch
dm-treat-alloc_dax-eopnotsupp-failure-as-non-fatal.patch
dcssblk-handle-alloc_dax-eopnotsupp-failure.patch
virtio-treat-alloc_dax-eopnotsupp-failure-as-non-fatal.patch
dax-check-for-data-cache-aliasing-at-runtime.patch
introduce-cpu_dcache_is_aliasing-across-all-architectures.patch
dax-fix-incorrect-list-of-data-cache-aliasing-architectures.patch
nvdimm-pmem-cleanup-alloc_dax-error-handling.patch
dm-cleanup-alloc_dax-error-handling.patch
dcssblk-cleanup-alloc_dax-error-handling.patch
virtio-cleanup-alloc_dax-error-handling.patch