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, 78 insertions, 0 deletions

diff --git a/fs/fuse/Kconfig b/fs/fuse/Kconfig
new file mode 100644
index 000000000..3a4ae632c
--- /dev/null
+++ b/fs/fuse/Kconfig
@@ -0,0 +1,78 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config FUSE_FS
+	tristate "FUSE (Filesystem in Userspace) support"
+	select FS_POSIX_ACL
+	select FS_IOMAP
+	help
+	  With FUSE it is possible to implement a fully functional filesystem
+	  in a userspace program.
+
+	  There's also a companion library: libfuse2.  This library is available
+	  from the FUSE homepage:
+	  <https://github.com/libfuse/>
+	  although chances are your distribution already has that library
+	  installed if you've installed the "fuse" package itself.
+
+	  See <file:Documentation/filesystems/fuse/fuse.rst> for more information.
+	  See <file:Documentation/Changes> for needed library/utility version.
+
+	  If you want to develop a userspace FS, or if you want to use
+	  a filesystem based on FUSE, answer Y or M.
+
+config CUSE
+	tristate "Character device in Userspace support"
+	depends on FUSE_FS
+	help
+	  This FUSE extension allows character devices to be
+	  implemented in userspace.
+
+	  If you want to develop or use a userspace character device
+	  based on CUSE, answer Y or M.
+
+config VIRTIO_FS
+	tristate "Virtio Filesystem"
+	depends on FUSE_FS
+	select VIRTIO
+	help
+	  The Virtio Filesystem allows guests to mount file systems from the
+	  host.
+
+	  If you want to share files between guests or with the host, answer Y
+	  or M.
+
+config FUSE_DAX
+	bool "Virtio Filesystem Direct Host Memory Access support"
+	default y
+	select INTERVAL_TREE
+	depends on VIRTIO_FS
+	depends on FS_DAX
+	depends on DAX
+	help
+	  This allows bypassing guest page cache and allows mapping host page
+	  cache directly in guest address space.
+
+	  If you want to allow mounting a Virtio Filesystem with the "dax"
+	  option, answer Y.
+
+config FUSE_PASSTHROUGH
+	bool "FUSE passthrough operations support"
+	default y
+	depends on FUSE_FS
+	select FS_STACK
+	help
+	  This allows bypassing FUSE server by mapping specific FUSE operations
+	  to be performed directly on a backing file.
+
+	  If you want to allow passthrough operations, answer Y.
+
+config FUSE_IO_URING
+	bool "FUSE communication over io-uring"
+	default y
+	depends on FUSE_FS
+	depends on IO_URING
+	help
+	  This allows sending FUSE requests over the io-uring interface and
+          also adds request core affinity.
+
+	  If you want to allow fuse server/client communication through io-uring,
+	  answer Y