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

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

[Andrew Morton]

The patch titled
     Subject: nvdimm/pmem: cleanup alloc_dax() error handling
has been added to the -mm mm-unstable branch.  Its filename is
     nvdimm-pmem-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/nvdimm-pmem-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: nvdimm/pmem: cleanup alloc_dax() error handling
Date: Thu, 8 Feb 2024 13:49:10 -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/20240208184913.484340-10-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/nvdimm/pmem.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/nvdimm/pmem.c~nvdimm-pmem-cleanup-alloc_dax-error-handling
+++ a/drivers/nvdimm/pmem.c
@@ -558,8 +558,8 @@ static int pmem_attach_disk(struct devic
 	disk->bb = &pmem->bb;
 
 	dax_dev = alloc_dax(pmem, &pmem_dax_ops);
-	if (IS_ERR_OR_NULL(dax_dev)) {
-		rc = IS_ERR(dax_dev) ? PTR_ERR(dax_dev) : -EOPNOTSUPP;
+	if (IS_ERR(dax_dev)) {
+		rc = PTR_ERR(dax_dev);
 		if (rc != -EOPNOTSUPP)
 			goto out;
 	} else {
_

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