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, 64 insertions, 0 deletions

diff --git a/drivers/usb/chipidea/Kconfig b/drivers/usb/chipidea/Kconfig
new file mode 100644
index 000000000..bab45bc62
--- /dev/null
+++ b/drivers/usb/chipidea/Kconfig
@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config USB_CHIPIDEA
+	tristate "ChipIdea Highspeed Dual Role Controller"
+	depends on ((USB_EHCI_HCD && USB_GADGET) || (USB_EHCI_HCD && !USB_GADGET) || (!USB_EHCI_HCD && USB_GADGET)) && HAS_DMA
+	select EXTCON
+	select RESET_CONTROLLER
+	select USB_ULPI_BUS
+	select USB_ROLE_SWITCH
+	select USB_TEGRA_PHY if ARCH_TEGRA
+	help
+	  Say Y here if your system has a dual role high speed USB
+	  controller based on ChipIdea silicon IP. It supports:
+	  Dual-role switch (ID, OTG FSM, sysfs), Host-only, and
+	  Peripheral-only.
+
+	  When compiled dynamically, the module will be called ci_hdrc.ko.
+
+if USB_CHIPIDEA
+
+config USB_CHIPIDEA_UDC
+	bool "ChipIdea device controller"
+	depends on USB_GADGET
+	help
+	  Say Y here to enable device controller functionality of the
+	  ChipIdea driver.
+
+config USB_CHIPIDEA_HOST
+	bool "ChipIdea host controller"
+	depends on USB_EHCI_HCD
+	select USB_EHCI_ROOT_HUB_TT
+	help
+	  Say Y here to enable host controller functionality of the
+	  ChipIdea driver.
+
+config USB_CHIPIDEA_PCI
+	tristate "Enable PCI glue driver" if EXPERT
+	depends on USB_PCI
+	depends on NOP_USB_XCEIV
+	default USB_CHIPIDEA
+
+config USB_CHIPIDEA_MSM
+	tristate "Enable MSM hsusb glue driver" if EXPERT
+	default USB_CHIPIDEA
+
+config USB_CHIPIDEA_NPCM
+	tristate "Enable NPCM hsusb glue driver" if EXPERT
+	default USB_CHIPIDEA
+
+config USB_CHIPIDEA_IMX
+	tristate "Enable i.MX USB glue driver" if EXPERT
+	depends on OF
+	default USB_CHIPIDEA
+
+config USB_CHIPIDEA_GENERIC
+	tristate "Enable generic USB2 glue driver" if EXPERT
+	default USB_CHIPIDEA
+
+config USB_CHIPIDEA_TEGRA
+	tristate "Enable Tegra USB glue driver" if EXPERT
+	depends on OF
+	default USB_CHIPIDEA
+
+endif