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, 68 insertions, 0 deletions

diff --git a/drivers/usb/atm/Kconfig b/drivers/usb/atm/Kconfig
new file mode 100644
index 000000000..3d958a1a1
--- /dev/null
+++ b/drivers/usb/atm/Kconfig
@@ -0,0 +1,68 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# USB/ATM DSL configuration
+#
+
+menuconfig USB_ATM
+	tristate "USB DSL modem support"
+	depends on ATM
+	select CRC32
+	help
+	  Say Y here if you want to connect a USB Digital Subscriber Line (DSL)
+	  modem to your computer's USB port.  You will then need to choose your
+	  modem from the list below.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called usbatm.
+
+if USB_ATM
+
+config USB_SPEEDTOUCH
+	tristate "Speedtouch USB support"
+	select FW_LOADER
+	help
+	  Say Y here if you have an SpeedTouch USB or SpeedTouch 330
+	  modem.  In order to use your modem you will need to install the 
+	  two parts of the firmware, extracted by the user space tools; see
+	  <http://www.linux-usb.org/SpeedTouch/> for details.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called speedtch.
+
+config USB_CXACRU
+	tristate "Conexant AccessRunner USB support"
+	select FW_LOADER
+	help
+	  Say Y here if you have an ADSL USB modem based on the Conexant
+	  AccessRunner chipset.  In order to use your modem you will need to
+	  install the firmware, extracted by the user space tools; see
+	  <http://accessrunner.sourceforge.net/> for details.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cxacru.
+
+config USB_UEAGLEATM
+	tristate "ADI 930 and eagle USB DSL modem"
+	select FW_LOADER
+	help
+	  Say Y here if you have an ADSL USB modem based on the ADI 930
+	  or eagle chipset. In order to use your modem you will need to
+	  install firmwares and CMV (Command Management Variables); see
+	  <https://gna.org/projects/ueagleatm/> for details.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ueagle-atm.
+
+config USB_XUSBATM
+	tristate "Other USB DSL modem support"
+	help
+	  Say Y here if you have a DSL USB modem not explicitly supported by
+	  another USB DSL drivers.  In order to use your modem you will need to
+	  pass the vendor ID, product ID, and endpoint numbers for transmission
+	  and reception as module parameters.  You may need to initialize
+	  the modem using a user space utility (a firmware loader for example).
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called xusbatm.
+
+endif # USB_ATM