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, 36 insertions, 0 deletions

diff --git a/drivers/usb/musb/Makefile b/drivers/usb/musb/Makefile
new file mode 100644
index 000000000..5dccf0e45
--- /dev/null
+++ b/drivers/usb/musb/Makefile
@@ -0,0 +1,36 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# for USB OTG silicon based on Mentor Graphics INVENTRA designs
+#
+
+# define_trace.h needs to know how to find our header
+CFLAGS_musb_trace.o	:= -I$(src)
+
+obj-$(CONFIG_USB_MUSB_HDRC) += musb_hdrc.o
+
+musb_hdrc-y := musb_core.o musb_trace.o
+
+musb_hdrc-$(CONFIG_USB_MUSB_HOST)$(CONFIG_USB_MUSB_DUAL_ROLE) += musb_virthub.o musb_host.o
+musb_hdrc-$(CONFIG_USB_MUSB_GADGET)$(CONFIG_USB_MUSB_DUAL_ROLE) += musb_gadget_ep0.o musb_gadget.o
+musb_hdrc-$(CONFIG_DEBUG_FS)			+= musb_debugfs.o
+
+# Hardware Glue Layer
+obj-$(CONFIG_USB_MUSB_OMAP2PLUS)		+= omap2430.o
+obj-$(CONFIG_USB_MUSB_DSPS)			+= musb_dsps.o
+obj-$(CONFIG_USB_MUSB_TUSB6010)			+= tusb6010.o
+obj-$(CONFIG_USB_MUSB_DA8XX)			+= da8xx.o
+obj-$(CONFIG_USB_MUSB_UX500)			+= ux500.o
+obj-$(CONFIG_USB_MUSB_JZ4740)			+= jz4740.o
+obj-$(CONFIG_USB_MUSB_SUNXI)			+= sunxi.o
+obj-$(CONFIG_USB_MUSB_MEDIATEK)      		+= mediatek.o
+obj-$(CONFIG_USB_MUSB_POLARFIRE_SOC)		+= mpfs.o
+
+# the kconfig must guarantee that only one of the
+# possible I/O schemes will be enabled at a time ...
+# PIO only, or DMA (several potential schemes).
+# though PIO is always there to back up DMA, and for ep0
+
+musb_hdrc-$(CONFIG_USB_INVENTRA_DMA)		+= musbhsdma.o
+musb_hdrc-$(CONFIG_USB_TUSB_OMAP_DMA)		+= tusb6010_omap.o
+musb_hdrc-$(CONFIG_USB_UX500_DMA)		+= ux500_dma.o
+musb_hdrc-$(CONFIG_USB_TI_CPPI41_DMA)		+= musb_cppi41.o