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, 59 insertions, 0 deletions

diff --git a/drivers/clk/sprd/composite.c b/drivers/clk/sprd/composite.c
new file mode 100644
index 000000000..ad6b6383e
--- /dev/null
+++ b/drivers/clk/sprd/composite.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Spreadtrum composite clock driver
+//
+// Copyright (C) 2017 Spreadtrum, Inc.
+// Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
+
+#include <linux/clk-provider.h>
+
+#include "composite.h"
+
+static int sprd_comp_determine_rate(struct clk_hw *hw,
+				    struct clk_rate_request *req)
+{
+	struct sprd_comp *cc = hw_to_sprd_comp(hw);
+
+	return divider_determine_rate(hw, req, NULL, cc->div.width, 0);
+}
+
+static unsigned long sprd_comp_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	struct sprd_comp *cc = hw_to_sprd_comp(hw);
+
+	return sprd_div_helper_recalc_rate(&cc->common, &cc->div, parent_rate);
+}
+
+static int sprd_comp_set_rate(struct clk_hw *hw, unsigned long rate,
+			     unsigned long parent_rate)
+{
+	struct sprd_comp *cc = hw_to_sprd_comp(hw);
+
+	return sprd_div_helper_set_rate(&cc->common, &cc->div,
+				       rate, parent_rate);
+}
+
+static u8 sprd_comp_get_parent(struct clk_hw *hw)
+{
+	struct sprd_comp *cc = hw_to_sprd_comp(hw);
+
+	return sprd_mux_helper_get_parent(&cc->common, &cc->mux);
+}
+
+static int sprd_comp_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct sprd_comp *cc = hw_to_sprd_comp(hw);
+
+	return sprd_mux_helper_set_parent(&cc->common, &cc->mux, index);
+}
+
+const struct clk_ops sprd_comp_ops = {
+	.get_parent	= sprd_comp_get_parent,
+	.set_parent	= sprd_comp_set_parent,
+
+	.determine_rate	= sprd_comp_determine_rate,
+	.recalc_rate	= sprd_comp_recalc_rate,
+	.set_rate	= sprd_comp_set_rate,
+};
+EXPORT_SYMBOL_GPL(sprd_comp_ops);