x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted

The local "root" pointer is a temporary variable used during the device
search. Therefore, refcount related to the search iterators should be cleaned
up after the search is complete.

Use the __free() cleanup macro to ensure the refcount is decremented when the
temporary pointer goes out of scope.

Additionally, increment the refcount when caching a root pointer. This ensures
the in-use refcount is separate from the temporary search refcounting.

Finally, drop the redundant "root = NULL" before the second search loop. The
pci_get_class() iterator always decrements the refcount of its "from"
argument, so the first loop can only fall through with "root" already NULL.

Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching")
Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com
Reported-by: Sashiko <sashiko-bot@kernel.org>
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com

1 files changed, 38 insertions, 0 deletions

diff --git a/fs/hfsplus/xattr_user.c b/fs/hfsplus/xattr_user.c
new file mode 100644
index 000000000..6464b6c3d
--- /dev/null
+++ b/fs/hfsplus/xattr_user.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/hfsplus/xattr_user.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Handler for user extended attributes.
+ */
+
+#include <linux/nls.h>
+
+#include "hfsplus_fs.h"
+#include "xattr.h"
+
+static int hfsplus_user_getxattr(const struct xattr_handler *handler,
+				 struct dentry *unused, struct inode *inode,
+				 const char *name, void *buffer, size_t size)
+{
+
+	return hfsplus_getxattr(inode, name, buffer, size,
+				XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
+}
+
+static int hfsplus_user_setxattr(const struct xattr_handler *handler,
+				 struct mnt_idmap *idmap,
+				 struct dentry *unused, struct inode *inode,
+				 const char *name, const void *buffer,
+				 size_t size, int flags)
+{
+	return hfsplus_setxattr(inode, name, buffer, size, flags,
+				XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
+}
+
+const struct xattr_handler hfsplus_xattr_user_handler = {
+	.prefix	= XATTR_USER_PREFIX,
+	.get	= hfsplus_user_getxattr,
+	.set	= hfsplus_user_setxattr,
+};