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, 29 insertions, 0 deletions

diff --git a/drivers/usb/dwc2/Makefile b/drivers/usb/dwc2/Makefile
new file mode 100644
index 000000000..2bcd6945d
--- /dev/null
+++ b/drivers/usb/dwc2/Makefile
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0
+ccflags-$(CONFIG_USB_DWC2_DEBUG)	+= -DDEBUG
+ccflags-$(CONFIG_USB_DWC2_VERBOSE)	+= -DVERBOSE_DEBUG
+
+obj-$(CONFIG_USB_DWC2)			+= dwc2.o
+dwc2-y					:= core.o core_intr.o platform.o drd.o
+dwc2-y					+= params.o
+
+ifneq ($(filter y,$(CONFIG_USB_DWC2_HOST) $(CONFIG_USB_DWC2_DUAL_ROLE)),)
+	dwc2-y				+= hcd.o hcd_intr.o
+	dwc2-y				+= hcd_queue.o hcd_ddma.o
+endif
+
+ifneq ($(filter y,$(CONFIG_USB_DWC2_PERIPHERAL) $(CONFIG_USB_DWC2_DUAL_ROLE)),)
+	dwc2-y       			+= gadget.o
+endif
+
+ifneq ($(CONFIG_DEBUG_FS),)
+	dwc2-y				+= debugfs.o
+endif
+
+# NOTE: The previous s3c-hsotg peripheral mode only driver has been moved to
+# this location and renamed gadget.c. When building for dynamically linked
+# modules, dwc2.ko will get built for host mode, peripheral mode, and dual-role
+# mode. The PCI bus interface module will called dwc2_pci.ko and the platform
+# interface module will be called dwc2_platform.ko.
+
+obj-$(CONFIG_USB_DWC2_PCI)		+= dwc2_pci.o
+dwc2_pci-y				:= pci.o