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, 56 insertions, 0 deletions

diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig
new file mode 100644
index 000000000..63a656449
--- /dev/null
+++ b/drivers/soc/aspeed/Kconfig
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+if ARCH_ASPEED || COMPILE_TEST
+
+menu "ASPEED SoC drivers"
+
+config ASPEED_LPC_CTRL
+	tristate "ASPEED LPC firmware cycle control"
+	select REGMAP
+	select MFD_SYSCON
+	default ARCH_ASPEED
+	help
+	  Control LPC firmware cycle mappings through ioctl()s. The driver
+	  also provides a read/write interface to a BMC ram region where the
+	  host LPC read/write region can be buffered.
+
+config ASPEED_LPC_SNOOP
+	tristate "ASPEED LPC snoop support"
+	select REGMAP
+	select MFD_SYSCON
+	default ARCH_ASPEED
+	help
+	  Provides a driver to control the LPC snoop interface which
+	  allows the BMC to listen on and save the data written by
+	  the host to an arbitrary LPC I/O port.
+
+config ASPEED_UART_ROUTING
+	tristate "ASPEED uart routing control"
+	select REGMAP
+	select MFD_SYSCON
+	default ARCH_ASPEED
+	help
+	  Provides a driver to control the UART routing paths, allowing
+	  users to perform runtime configuration of the RX muxes among
+	  the UART controllers and I/O pins.
+
+config ASPEED_P2A_CTRL
+	tristate "ASPEED P2A (VGA MMIO to BMC) bridge control"
+	select REGMAP
+	select MFD_SYSCON
+	default ARCH_ASPEED
+	help
+	  Control ASPEED P2A VGA MMIO to BMC mappings through ioctl()s.  The
+	  driver also provides an interface for userspace mappings to a
+	  pre-defined region.
+
+config ASPEED_SOCINFO
+	bool "ASPEED SoC Information driver"
+	select SOC_BUS
+	default ARCH_ASPEED
+	help
+	  Say yes to support decoding of ASPEED BMC information.
+
+endmenu
+
+endif