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, 162 insertions, 0 deletions

diff --git a/Documentation/networking/kapi.rst b/Documentation/networking/kapi.rst
new file mode 100644
index 000000000..98682b9a1
--- /dev/null
+++ b/Documentation/networking/kapi.rst
@@ -0,0 +1,162 @@
+=========================================
+Linux Networking and Network Devices APIs
+=========================================
+
+Linux Networking
+================
+
+Networking Base Types
+---------------------
+
+.. kernel-doc:: include/linux/net.h
+   :internal:
+
+Socket Buffer Functions
+-----------------------
+
+.. kernel-doc:: include/linux/skbuff.h
+   :internal:
+
+.. kernel-doc:: include/net/sock.h
+   :internal:
+
+.. kernel-doc:: net/socket.c
+   :export:
+
+.. kernel-doc:: net/core/skbuff.c
+   :export:
+
+.. kernel-doc:: net/core/sock.c
+   :export:
+
+.. kernel-doc:: net/core/datagram.c
+   :export:
+
+.. kernel-doc:: net/core/stream.c
+   :export:
+
+Socket Filter
+-------------
+
+.. kernel-doc:: net/core/filter.c
+   :export:
+
+Generic Network Statistics
+--------------------------
+
+.. kernel-doc:: include/uapi/linux/gen_stats.h
+   :internal:
+
+.. kernel-doc:: net/core/gen_stats.c
+   :export:
+
+.. kernel-doc:: net/core/gen_estimator.c
+   :export:
+
+SUN RPC subsystem
+-----------------
+
+.. kernel-doc:: net/sunrpc/xdr.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/svc_xprt.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/xprt.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/sched.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/socklib.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/stats.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/rpc_pipe.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/rpcb_clnt.c
+   :export:
+
+.. kernel-doc:: net/sunrpc/clnt.c
+   :export:
+
+Network device support
+======================
+
+Driver Support
+--------------
+
+.. kernel-doc:: net/core/dev.c
+   :export:
+
+.. kernel-doc:: net/ethernet/eth.c
+   :export:
+
+.. kernel-doc:: net/sched/sch_generic.c
+   :export:
+
+.. kernel-doc:: include/linux/etherdevice.h
+   :internal:
+
+.. kernel-doc:: include/linux/netdevice.h
+   :internal:
+
+.. kernel-doc:: include/net/net_shaper.h
+   :internal:
+
+PHY Support
+-----------
+
+.. kernel-doc:: drivers/net/phy/phy.c
+   :export:
+
+.. kernel-doc:: drivers/net/phy/phy.c
+   :internal:
+
+.. kernel-doc:: drivers/net/phy/phy-core.c
+   :export:
+
+.. kernel-doc:: drivers/net/phy/phy-c45.c
+   :export:
+
+.. kernel-doc:: include/linux/phy.h
+   :internal:
+
+.. kernel-doc:: drivers/net/phy/phy_device.c
+   :export:
+
+.. kernel-doc:: drivers/net/phy/phy_device.c
+   :internal:
+
+.. kernel-doc:: drivers/net/phy/mdio_bus.c
+   :export:
+
+.. kernel-doc:: drivers/net/phy/mdio_bus.c
+   :internal:
+
+PHYLINK
+-------
+
+  PHYLINK interfaces traditional network drivers with PHYLIB, fixed-links,
+  and SFF modules (eg, hot-pluggable SFP) that may contain PHYs.  PHYLINK
+  provides management of the link state and link modes.
+
+.. kernel-doc:: include/linux/phylink.h
+   :internal:
+
+.. kernel-doc:: drivers/net/phy/phylink.c
+
+SFP support
+-----------
+
+.. kernel-doc:: drivers/net/phy/sfp-bus.c
+   :internal:
+
+.. kernel-doc:: include/linux/sfp.h
+   :internal:
+
+.. kernel-doc:: drivers/net/phy/sfp-bus.c
+   :export: