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

5 files changed, 103 insertions, 0 deletions

diff --git a/arch/mips/mobileye/Kconfig b/arch/mips/mobileye/Kconfig
new file mode 100644
index 000000000..8a4868d2e
--- /dev/null
+++ b/arch/mips/mobileye/Kconfig
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0
+if EYEQ
+
+choice
+	prompt "Mobileye EyeQ SoC selection"
+	default MACH_EYEQ5
+	help
+	  Select Mobileye EyeQ MIPS SoC type.
+
+	config MACH_EYEQ5
+		bool "Mobileye EyeQ5 SoC"
+
+	config MACH_EYEQ6H
+		bool "Mobileye EyeQ6H SoC"
+
+	config MACH_EYEQ6LPLUS
+		bool "Mobileye EyeQ6Lplus SoC"
+endchoice
+
+config FIT_IMAGE_FDT_EPM5
+	bool "Include FDT for Mobileye EyeQ5 development platforms"
+	depends on MACH_EYEQ5
+	default n
+	help
+	  Enable this to include the FDT for the EyeQ5 development platforms
+	  from Mobileye in the FIT kernel image.
+	  This requires u-boot on the platform.
+
+endif
diff --git a/arch/mips/mobileye/Makefile b/arch/mips/mobileye/Makefile
new file mode 100644
index 000000000..315c06b68
--- /dev/null
+++ b/arch/mips/mobileye/Makefile
@@ -0,0 +1 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
diff --git a/arch/mips/mobileye/Platform b/arch/mips/mobileye/Platform
new file mode 100644
index 000000000..93b533492
--- /dev/null
+++ b/arch/mips/mobileye/Platform
@@ -0,0 +1,17 @@
+#
+# Copyright (C) 2016 Imagination Technologies
+# Author: Paul Burton <paul.burton@mips.com>
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation;  either version 2 of the  License, or (at your
+# option) any later version.
+#
+
+load-$(CONFIG_MACH_EYEQ5)	= 0xa800000808000000
+load-$(CONFIG_MACH_EYEQ6H)	= 0xa800000100800000
+load-$(CONFIG_MACH_EYEQ6LPLUS)	= 0xa800000108800000
+all-$(CONFIG_MACH_EYEQ5)	+= vmlinux.gz.itb
+
+its-y					:= vmlinux.its.S
+its-$(CONFIG_FIT_IMAGE_FDT_EPM5)	+= board-epm5.its.S
diff --git a/arch/mips/mobileye/board-epm5.its.S b/arch/mips/mobileye/board-epm5.its.S
new file mode 100644
index 000000000..08e8c4f18
--- /dev/null
+++ b/arch/mips/mobileye/board-epm5.its.S
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
+/ {
+	images {
+		fdt-mobileye-epm5 {
+			description = "Mobileeye MP5 Device Tree";
+			data = /incbin/("boot/dts/mobileye/eyeq5-epm5.dtb");
+			type = "flat_dt";
+			arch = "mips";
+			compression = "none";
+			hash {
+				algo = "sha1";
+			};
+		};
+	};
+
+    configurations {
+		default = "conf-1";
+		conf-1 {
+			description = "Mobileye EPM5 Linux kernel";
+			kernel = "kernel";
+			fdt = "fdt-mobileye-epm5";
+		};
+	};
+};
diff --git a/arch/mips/mobileye/vmlinux.its.S b/arch/mips/mobileye/vmlinux.its.S
new file mode 100644
index 000000000..3e2546765
--- /dev/null
+++ b/arch/mips/mobileye/vmlinux.its.S
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/dts-v1/;
+
+/ {
+	description = KERNEL_NAME;
+	#address-cells = <ADDR_CELLS>;
+
+	images {
+		kernel {
+			description = KERNEL_NAME;
+			data = /incbin/(VMLINUX_BINARY);
+			type = "kernel";
+			arch = "mips";
+			os = "linux";
+			compression = VMLINUX_COMPRESSION;
+			load = /bits/ ADDR_BITS <VMLINUX_LOAD_ADDRESS>;
+			entry = /bits/ ADDR_BITS <VMLINUX_ENTRY_ADDRESS>;
+			hash {
+				algo = "sha1";
+			};
+		};
+	};
+
+	configurations {
+		default = "conf-default";
+
+		conf-default {
+			description = "Generic Linux kernel";
+			kernel = "kernel";
+		};
+	};
+};