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, 37 insertions, 0 deletions

diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile
new file mode 100644
index 000000000..01745eca1
--- /dev/null
+++ b/drivers/mtd/maps/Makefile
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# linux/drivers/maps/Makefile
+#
+
+ifeq ($(CONFIG_MTD_COMPLEX_MAPPINGS),y)
+obj-$(CONFIG_MTD)		+= map_funcs.o
+endif
+
+# Chip mappings
+obj-$(CONFIG_MTD_CFI_FLAGADM)	+= cfi_flagadm.o
+obj-$(CONFIG_MTD_DC21285)	+= dc21285.o
+obj-$(CONFIG_MTD_L440GX)	+= l440gx.o
+obj-$(CONFIG_MTD_AMD76XROM)	+= amd76xrom.o
+obj-$(CONFIG_MTD_ESB2ROM)	+= esb2rom.o
+obj-$(CONFIG_MTD_ICHXROM)	+= ichxrom.o
+obj-$(CONFIG_MTD_CK804XROM)	+= ck804xrom.o
+obj-$(CONFIG_MTD_TSUNAMI)	+= tsunami_flash.o
+obj-$(CONFIG_MTD_PXA2XX)	+= pxa2xx-flash.o
+obj-$(CONFIG_MTD_PHYSMAP)	+= physmap.o
+physmap-y			:= physmap-core.o
+physmap-$(CONFIG_MTD_PHYSMAP_VERSATILE) += physmap-versatile.o
+physmap-$(CONFIG_MTD_PHYSMAP_GEMINI) += physmap-gemini.o
+physmap-$(CONFIG_MTD_PHYSMAP_IXP4XX) += physmap-ixp4xx.o
+obj-$(CONFIG_MTD_PISMO)		+= pismo.o
+obj-$(CONFIG_MTD_PCMCIA)	+= pcmciamtd.o
+obj-$(CONFIG_MTD_SA1100)	+= sa1100-flash.o
+obj-$(CONFIG_MTD_SBC_GXX)	+= sbc_gxx.o
+obj-$(CONFIG_MTD_SUN_UFLASH)	+= sun_uflash.o
+obj-$(CONFIG_MTD_SCx200_DOCFLASH)+= scx200_docflash.o
+obj-$(CONFIG_MTD_SOLUTIONENGINE)+= solutionengine.o
+obj-$(CONFIG_MTD_PCI)		+= pci.o
+obj-$(CONFIG_MTD_UCLINUX)	+= uclinux.o
+obj-$(CONFIG_MTD_SCB2_FLASH)	+= scb2_flash.o
+obj-$(CONFIG_MTD_PLATRAM)	+= plat-ram.o
+obj-$(CONFIG_MTD_VMU)		+= vmu-flash.o
+obj-$(CONFIG_MTD_LANTIQ)	+= lantiq-flash.o