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, 75 insertions, 0 deletions

diff --git a/lib/raid/Kconfig b/lib/raid/Kconfig
new file mode 100644
index 000000000..01f007b25
--- /dev/null
+++ b/lib/raid/Kconfig
@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config XOR_BLOCKS
+	tristate
+
+# selected by architectures that provide an optimized XOR implementation
+config XOR_BLOCKS_ARCH
+	depends on XOR_BLOCKS
+	default y if ALPHA
+	default y if ARM
+	default y if ARM64
+	default y if CPU_HAS_LSX		# loongarch
+	default y if ALTIVEC			# powerpc
+	default y if RISCV_ISA_V
+	default y if SPARC
+	default y if S390
+	default y if X86_32
+	default y if X86_64
+	bool
+
+config XOR_KUNIT_TEST
+	tristate "KUnit tests for xor_gen" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	depends on XOR_BLOCKS
+	default KUNIT_ALL_TESTS
+	help
+	  Unit tests for the XOR library functions.
+
+	  This is intended to help people writing architecture-specific
+	  optimized versions.  If unsure, say N.
+
+config XOR_BENCHMARK
+	bool "Benchmark for xor_gen"
+	depends on XOR_KUNIT_TEST
+	help
+	  Include benchmarks in the KUnit test suite for xor_gen.
+
+config RAID6_PQ
+	tristate
+
+# selected by architectures that provide an optimized PQ implementation
+config RAID6_PQ_ARCH
+	depends on RAID6_PQ
+	default y if KERNEL_MODE_NEON		# arm32/arm64
+	default y if LOONGARCH
+	default y if ALTIVEC			# powerpc
+	default y if RISCV_ISA_V
+	default y if S390
+	default y if X86
+	bool
+
+config RAID6_PQ_KUNIT_TEST
+	tristate "KUnit tests for RAID6 PQ functions" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	depends on RAID6_PQ
+	default KUNIT_ALL_TESTS
+	help
+	  Unit tests for the RAID6 PQ library functions.
+
+	  This is intended to help people writing architecture-specific
+	  optimized versions.  If unsure, say N.
+
+config RAID6_PQ_KUNIT_BENCHMARK
+	bool "Benchmark for RAID6 PQ"
+	depends on RAID6_PQ_KUNIT_TEST
+	help
+	  Include benchmarks in the KUnit test suite for raid P/Q generation.
+
+config RAID6_PQ_BENCHMARK
+	bool "Automatically choose fastest RAID6 PQ functions"
+	depends on RAID6_PQ
+	default y
+	help
+	  Benchmark all available RAID6 PQ functions on init and choose the
+	  fastest one.