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, 48 insertions, 0 deletions

diff --git a/drivers/misc/eeprom/Kconfig b/drivers/misc/eeprom/Kconfig
new file mode 100644
index 000000000..d6af02588
--- /dev/null
+++ b/drivers/misc/eeprom/Kconfig
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menu "EEPROM support"
+
+config EEPROM_MAX6875
+	tristate "Maxim MAX6874/5 power supply supervisor"
+	depends on I2C
+	help
+	  If you say yes here you get read-only support for the user EEPROM of
+	  the Maxim MAX6874/5 EEPROM-programmable, quad power-supply
+	  sequencer/supervisor.
+
+	  All other features of this chip should be accessed via i2c-dev.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called max6875.
+
+
+config EEPROM_93CX6
+	tristate "EEPROM 93CX6 support"
+	help
+	  This is a driver for the EEPROM chipsets 93c46 and 93c66.
+	  The driver supports both read as well as write commands.
+
+	  If unsure, say N.
+
+config EEPROM_DIGSY_MTC_CFG
+	bool "DigsyMTC display configuration EEPROMs device"
+	depends on GPIO_MPC5200 && SPI_GPIO
+	help
+	  This option enables access to display configuration EEPROMs
+	  on digsy_mtc board. You have to additionally select Microwire
+	  EEPROM 93XX46 driver. sysfs entries will be created for that
+	  EEPROM allowing to read/write the configuration data or to
+	  erase the whole EEPROM.
+
+	  If unsure, say N.
+
+config EEPROM_IDT_89HPESX
+	tristate "IDT 89HPESx PCIe-switches EEPROM / CSR support"
+	depends on I2C && SYSFS
+	help
+	  Enable this driver to get read/write access to EEPROM / CSRs
+	  over IDT PCIe-switch i2c-slave interface.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called idt_89hpesx.
+
+endmenu