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, 145 insertions, 0 deletions

diff --git a/drivers/input/rmi4/Kconfig b/drivers/input/rmi4/Kconfig
new file mode 100644
index 000000000..5db58fc9e
--- /dev/null
+++ b/drivers/input/rmi4/Kconfig
@@ -0,0 +1,145 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# RMI4 configuration
+#
+config RMI4_CORE
+	tristate "Synaptics RMI4 bus support"
+	select IRQ_DOMAIN
+	help
+	  Say Y here if you want to support the Synaptics RMI4 bus.  This is
+	  required for all RMI4 device support.
+
+	  If unsure, say Y.
+
+if RMI4_CORE
+
+config RMI4_I2C
+	tristate "RMI4 I2C Support"
+	depends on I2C
+	help
+	  Say Y here if you want to support RMI4 devices connected to an I2C
+	  bus.
+
+	  If unsure, say Y.
+
+config RMI4_SPI
+	tristate "RMI4 SPI Support"
+	depends on SPI
+	help
+	  Say Y here if you want to support RMI4 devices connected to a SPI
+	  bus.
+
+	  If unsure, say N.
+
+config RMI4_SMB
+	tristate "RMI4 SMB Support"
+	depends on I2C
+	help
+	  Say Y here if you want to support RMI4 devices connected to an SMB
+	  bus.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called rmi_smbus.
+
+config RMI4_F03
+	bool "RMI4 Function 03 (PS2 Guest)"
+	depends on RMI4_CORE
+	help
+	  Say Y here if you want to add support for RMI4 function 03.
+
+	  Function 03 provides PS2 guest support for RMI4 devices. This
+	  includes support for TrackPoints on TouchPads.
+
+config RMI4_F03_SERIO
+	tristate
+	depends on RMI4_CORE
+	depends on RMI4_F03
+	default RMI4_CORE
+	select SERIO
+
+config RMI4_2D_SENSOR
+	bool
+
+config RMI4_F11
+	bool "RMI4 Function 11 (2D pointing)"
+	select RMI4_2D_SENSOR
+	help
+	  Say Y here if you want to add support for RMI4 function 11.
+
+	  Function 11 provides 2D multifinger pointing for touchscreens and
+	  touchpads. For sensors that support relative pointing, F11 also
+	  provides mouse input.
+
+config RMI4_F12
+	bool "RMI4 Function 12 (2D pointing)"
+	select RMI4_2D_SENSOR
+	help
+	  Say Y here if you want to add support for RMI4 function 12.
+
+	  Function 12 provides 2D multifinger pointing for touchscreens and
+	  touchpads. For sensors that support relative pointing, F12 also
+	  provides mouse input.
+
+config RMI4_F1A
+	bool "RMI4 Function 1A (0D pointing)"
+	help
+	  Say Y here if you want to add support for RMI4 function 1A.
+
+	  Function 1A provides capacitive keys support for RMI4 devices.
+
+config RMI4_F21
+	bool "RMI4 Function 21 (PRESSURE)"
+	help
+	  Say Y here if you want to add support for RMI4 function 21.
+
+	  Function 21 provides buttons/pressure handling for RMI4 devices.
+	  This includes support for buttons/pressure on PressurePad.
+
+config RMI4_F30
+	bool "RMI4 Function 30 (GPIO LED)"
+	help
+	  Say Y here if you want to add support for RMI4 function 30.
+
+	  Function 30 provides GPIO and LED support for RMI4 devices. This
+	  includes support for buttons on TouchPads and ClickPads.
+
+config RMI4_F34
+	bool "RMI4 Function 34 (Device reflash)"
+	select FW_LOADER
+	help
+	  Say Y here if you want to add support for RMI4 function 34.
+
+	  Function 34 provides support for upgrading the firmware on the RMI4
+	  device via the firmware loader interface. This is triggered using a
+	  sysfs attribute.
+
+config RMI4_F3A
+	bool "RMI4 Function 3A (GPIO)"
+	help
+	  Say Y here if you want to add support for RMI4 function 3A.
+
+	  Function 3A provides GPIO support for RMI4 devices. This includes
+	  support for buttons on TouchPads and ClickPads.
+
+config RMI4_F54
+	bool "RMI4 Function 54 (Analog diagnostics)"
+	depends on VIDEO_DEV=y || (RMI4_CORE=m && VIDEO_DEV=m)
+	select VIDEOBUF2_VMALLOC
+	select RMI4_F55
+	help
+	  Say Y here if you want to add support for RMI4 function 54
+
+	  Function 54 provides access to various diagnostic features in certain
+	  RMI4 touch sensors.
+
+config RMI4_F55
+	bool "RMI4 Function 55 (Sensor tuning)"
+	help
+	  Say Y here if you want to add support for RMI4 function 55
+
+	  Function 55 provides access to the RMI4 touch sensor tuning
+	  mechanism.
+
+endif # RMI_CORE