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, 86 insertions, 0 deletions

diff --git a/drivers/clk/sprd/composite.h b/drivers/clk/sprd/composite.h
new file mode 100644
index 000000000..15cec97d2
--- /dev/null
+++ b/drivers/clk/sprd/composite.h
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+//
+// Spreadtrum composite clock driver
+//
+// Copyright (C) 2017 Spreadtrum, Inc.
+// Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
+
+#ifndef _SPRD_COMPOSITE_H_
+#define _SPRD_COMPOSITE_H_
+
+#include "common.h"
+#include "mux.h"
+#include "div.h"
+
+struct sprd_comp {
+	struct sprd_mux_ssel	mux;
+	struct sprd_div_internal	div;
+	struct sprd_clk_common	common;
+};
+
+#define SPRD_COMP_CLK_HW_INIT_FN(_struct, _name, _parent, _reg, _table,	\
+				 _mshift, _mwidth, _doffset, _dshift,	\
+				 _dwidth, _flags, _fn)			\
+	struct sprd_comp _struct = {					\
+		.mux	= _SPRD_MUX_CLK(_mshift, _mwidth, _table),	\
+		.div	= _SPRD_DIV_CLK(_doffset, _dshift, _dwidth),	\
+		.common = {						\
+			.regmap		= NULL,				\
+			.reg		= _reg,				\
+			.hw.init = _fn(_name, _parent,			\
+				       &sprd_comp_ops, _flags),		\
+		}							\
+	}
+
+#define SPRD_COMP_CLK_TABLE(_struct, _name, _parent, _reg, _table,	\
+			    _mshift, _mwidth, _dshift, _dwidth, _flags)	\
+	SPRD_COMP_CLK_HW_INIT_FN(_struct, _name, _parent, _reg, _table,	\
+				 _mshift, _mwidth, 0x0, _dshift,	\
+				 _dwidth, _flags, CLK_HW_INIT_PARENTS)
+
+#define SPRD_COMP_CLK(_struct, _name, _parent, _reg, _mshift,		\
+		      _mwidth, _dshift, _dwidth, _flags)		\
+	SPRD_COMP_CLK_TABLE(_struct, _name, _parent, _reg, NULL,	\
+			    _mshift, _mwidth, _dshift, _dwidth, _flags)
+
+#define SPRD_COMP_CLK_DATA_TABLE(_struct, _name, _parent, _reg, _table,	\
+				 _mshift, _mwidth, _dshift,		\
+				 _dwidth, _flags)			\
+	SPRD_COMP_CLK_HW_INIT_FN(_struct, _name, _parent, _reg, _table,	\
+				 _mshift, _mwidth, 0x0, _dshift,	\
+				 _dwidth, _flags,			\
+				 CLK_HW_INIT_PARENTS_DATA)
+
+#define SPRD_COMP_CLK_DATA(_struct, _name, _parent, _reg, _mshift,	\
+			   _mwidth, _dshift, _dwidth, _flags)		\
+	SPRD_COMP_CLK_DATA_TABLE(_struct, _name, _parent, _reg, NULL,	\
+				 _mshift, _mwidth, _dshift, _dwidth,	\
+				 _flags)
+
+#define SPRD_COMP_CLK_DATA_TABLE_OFFSET(_struct, _name, _parent, _reg,	\
+					_table, _mshift, _mwidth,	\
+					_doffset, _dshift, _dwidth,	\
+					_flags)				\
+	SPRD_COMP_CLK_HW_INIT_FN(_struct, _name, _parent, _reg, _table,	\
+				 _mshift, _mwidth, _doffset, _dshift,	\
+				 _dwidth, _flags,			\
+				 CLK_HW_INIT_PARENTS_DATA)
+
+#define SPRD_COMP_CLK_DATA_OFFSET(_struct, _name, _parent, _reg,	\
+				  _mshift, _mwidth, _doffset, _dshift,	\
+				  _dwidth, _flags)			\
+	SPRD_COMP_CLK_DATA_TABLE_OFFSET(_struct, _name, _parent, _reg,	\
+					NULL, _mshift, _mwidth,		\
+					_doffset, _dshift, _dwidth,	\
+					_flags)
+
+static inline struct sprd_comp *hw_to_sprd_comp(const struct clk_hw *hw)
+{
+	struct sprd_clk_common *common = hw_to_sprd_clk_common(hw);
+
+	return container_of(common, struct sprd_comp, common);
+}
+
+extern const struct clk_ops sprd_comp_ops;
+
+#endif /* _SPRD_COMPOSITE_H_ */