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, 32 insertions, 0 deletions

diff --git a/include/crypto/streebog.h b/include/crypto/streebog.h
new file mode 100644
index 000000000..570f720a1
--- /dev/null
+++ b/include/crypto/streebog.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause */
+/*
+ * Copyright (c) 2013 Alexey Degtyarev <alexey@renatasystems.org>
+ * Copyright (c) 2018 Vitaly Chikunov <vt@altlinux.org>
+ *
+ * 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.
+ */
+
+#ifndef _CRYPTO_STREEBOG_H_
+#define _CRYPTO_STREEBOG_H_
+
+#include <linux/types.h>
+
+#define STREEBOG256_DIGEST_SIZE	32
+#define STREEBOG512_DIGEST_SIZE	64
+#define STREEBOG_BLOCK_SIZE	64
+
+struct streebog_uint512 {
+	__le64 qword[8];
+};
+
+struct streebog_state {
+	struct streebog_uint512 hash;
+	struct streebog_uint512 h;
+	struct streebog_uint512 N;
+	struct streebog_uint512 Sigma;
+};
+
+#endif /* !_CRYPTO_STREEBOG_H_ */