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, 63 insertions, 0 deletions

diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
new file mode 100644
index 000000000..f37971197
--- /dev/null
+++ b/drivers/usb/dwc3/Makefile
@@ -0,0 +1,63 @@
+# SPDX-License-Identifier: GPL-2.0
+# define_trace.h needs to know how to find our header
+CFLAGS_trace.o				:= -I$(src)
+
+obj-$(CONFIG_USB_DWC3)			+= dwc3.o
+
+dwc3-y					:= core.o
+
+ifneq ($(CONFIG_TRACING),)
+	dwc3-y				+= trace.o
+endif
+
+ifneq ($(filter y,$(CONFIG_USB_DWC3_HOST) $(CONFIG_USB_DWC3_DUAL_ROLE)),)
+	dwc3-y				+= host.o
+endif
+
+ifneq ($(filter y,$(CONFIG_USB_DWC3_GADGET) $(CONFIG_USB_DWC3_DUAL_ROLE)),)
+	dwc3-y				+= gadget.o ep0.o
+endif
+
+ifneq ($(CONFIG_USB_DWC3_DUAL_ROLE),)
+	dwc3-y				+= drd.o
+endif
+
+ifneq ($(CONFIG_USB_DWC3_ULPI),)
+	dwc3-y				+= ulpi.o
+endif
+
+ifneq ($(CONFIG_DEBUG_FS),)
+	dwc3-y				+= debugfs.o
+endif
+
+##
+# Platform-specific glue layers go here
+#
+# NOTICE: Make sure your glue layer doesn't depend on anything
+# which is arch-specific and that it compiles on all situations.
+#
+# We want to keep this requirement in order to be able to compile
+# the entire driver (with all its glue layers) on several architectures
+# and make sure it compiles fine. This will also help with allmodconfig
+# and allyesconfig builds.
+##
+
+obj-$(CONFIG_USB_DWC3_AM62)		+= dwc3-am62.o
+obj-$(CONFIG_USB_DWC3_APPLE)		+= dwc3-apple.o
+obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
+obj-$(CONFIG_USB_DWC3_EXYNOS)		+= dwc3-exynos.o
+obj-$(CONFIG_USB_DWC3_PCI)		+= dwc3-pci.o
+obj-$(CONFIG_USB_DWC3_HAPS)		+= dwc3-haps.o
+obj-$(CONFIG_USB_DWC3_KEYSTONE)		+= dwc3-keystone.o
+obj-$(CONFIG_USB_DWC3_MESON_G12A)	+= dwc3-meson-g12a.o
+obj-$(CONFIG_USB_DWC3_OF_SIMPLE)	+= dwc3-of-simple.o
+obj-$(CONFIG_USB_DWC3_ST)		+= dwc3-st.o
+obj-$(CONFIG_USB_DWC3_QCOM)		+= dwc3-qcom.o
+obj-$(CONFIG_USB_DWC3_QCOM)		+= dwc3-qcom-legacy.o
+obj-$(CONFIG_USB_DWC3_IMX8MP)		+= dwc3-imx8mp.o
+obj-$(CONFIG_USB_DWC3_IMX)		+= dwc3-imx.o
+obj-$(CONFIG_USB_DWC3_XILINX)		+= dwc3-xilinx.o
+obj-$(CONFIG_USB_DWC3_OCTEON)		+= dwc3-octeon.o
+obj-$(CONFIG_USB_DWC3_RTK)		+= dwc3-rtk.o
+obj-$(CONFIG_USB_DWC3_GENERIC_PLAT)	+= dwc3-generic-plat.o
+obj-$(CONFIG_USB_DWC3_GOOGLE)		+= dwc3-google.o