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, 175 insertions, 0 deletions

diff --git a/drivers/pinctrl/intel/Kconfig b/drivers/pinctrl/intel/Kconfig
new file mode 100644
index 000000000..04c3a5b58
--- /dev/null
+++ b/drivers/pinctrl/intel/Kconfig
@@ -0,0 +1,175 @@
+# SPDX-License-Identifier: GPL-2.0
+# Intel pin control drivers
+menu "Intel pinctrl drivers"
+	depends on (ACPI && X86) || COMPILE_TEST
+
+config PINCTRL_BAYTRAIL
+	bool "Intel Baytrail GPIO pin control"
+	select PINCTRL_INTEL
+	help
+	  driver for memory mapped GPIO functionality on Intel Baytrail
+	  platforms. Supports 3 banks with 102, 28 and 44 gpios.
+	  Most pins are usually muxed to some other functionality by firmware,
+	  so only a small amount is available for gpio use.
+
+	  Requires ACPI device enumeration code to set up a platform device.
+
+config PINCTRL_CHERRYVIEW
+	tristate "Intel Cherryview/Braswell pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  Cherryview/Braswell pinctrl driver provides an interface that
+	  allows configuring of SoC pins and using them as GPIOs.
+
+config PINCTRL_LYNXPOINT
+	tristate "Intel Lynxpoint pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  Lynxpoint is the PCH of Intel Haswell. This pinctrl driver
+	  provides an interface that allows configuring of PCH pins and
+	  using them as GPIOs.
+
+config PINCTRL_INTEL
+	tristate
+	select PINMUX
+	select PINCONF
+	select GENERIC_PINCONF
+	select GPIOLIB
+	select GPIOLIB_IRQCHIP
+
+config PINCTRL_INTEL_PLATFORM
+	tristate "Intel pinctrl and GPIO platform driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel PCH pins and using them as GPIOs. Currently the following
+	  Intel SoCs / platforms require this to be functional:
+	  - Lunar Lake
+	  - Nova Lake
+	  - Panther Lake
+
+config PINCTRL_ALDERLAKE
+	tristate "Intel Alder Lake pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  PCH pins of the following platforms and using them as GPIOs:
+	  - Alder Lake HX, N, and S
+	  - Raptor Lake HX, E, and S
+	  - Twin Lake
+
+config PINCTRL_BROXTON
+	tristate "Intel Broxton pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  Broxton pinctrl driver provides an interface that allows
+	  configuring of SoC pins and using them as GPIOs.
+
+config PINCTRL_CANNONLAKE
+	tristate "Intel Cannon Lake PCH pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Cannon Lake PCH pins and using them as GPIOs.
+
+config PINCTRL_CEDARFORK
+	tristate "Intel Cedar Fork pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Cedar Fork PCH pins and using them as GPIOs.
+
+config PINCTRL_DENVERTON
+	tristate "Intel Denverton pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Denverton SoC pins and using them as GPIOs.
+
+config PINCTRL_ELKHARTLAKE
+	tristate "Intel Elkhart Lake SoC pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Elkhart Lake SoC pins and using them as GPIOs.
+
+config PINCTRL_EMMITSBURG
+	tristate "Intel Emmitsburg pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Emmitsburg pins and using them as GPIOs.
+
+config PINCTRL_GEMINILAKE
+	tristate "Intel Gemini Lake SoC pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Gemini Lake SoC pins and using them as GPIOs.
+
+config PINCTRL_ICELAKE
+	tristate "Intel Ice Lake PCH pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Ice Lake PCH pins and using them as GPIOs.
+
+config PINCTRL_JASPERLAKE
+	tristate "Intel Jasper Lake PCH pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Jasper Lake PCH pins and using them as GPIOs.
+
+config PINCTRL_LAKEFIELD
+	tristate "Intel Lakefield SoC pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Lakefield SoC pins and using them as GPIOs.
+
+config PINCTRL_LEWISBURG
+	tristate "Intel Lewisburg pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  of Intel Lewisburg pins and using them as GPIOs.
+
+config PINCTRL_METEORLAKE
+	tristate "Intel Meteor Lake pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  SoC pins of the following platforms and using them as GPIOs:
+	  - Arrow Lake (all variants)
+	  - Meteor Lake (all variants)
+
+config PINCTRL_METEORPOINT
+	tristate "Intel Meteor Point pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  PCH pins of the following platforms and using them as GPIOs:
+	  - Arrow Lake HX and S
+
+config PINCTRL_SUNRISEPOINT
+	tristate "Intel Sunrisepoint pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  Sunrisepoint is the PCH of Intel Skylake. This pinctrl driver
+	  provides an interface that allows configuring of PCH pins and
+	  using them as GPIOs.
+
+config PINCTRL_TIGERLAKE
+	tristate "Intel Tiger Lake pinctrl and GPIO driver"
+	select PINCTRL_INTEL
+	help
+	  This pinctrl driver provides an interface that allows configuring
+	  PCH pins of the following platforms and using them as GPIOs:
+	  - Alder Lake H, P, PS, and U
+	  - Raptor Lake H, P, PS, PX, and U
+	  - Rocket Lake S
+	  - Tiger Lake (all variants)
+
+source "drivers/pinctrl/intel/Kconfig.tng"
+endmenu