selftests/bpf: Reject graph kptr use after RCU unlockgrafted

Add a sleepable verifier test that loads a graph-node local kptr in an
explicit RCU read-side critical section, then passes its node to
bpf_rbtree_remove() after the section ends.

Before the verifier fix, the stale NON_OWN_REF flag makes the node look like
a live borrowed reference and the program is accepted. After the fix, the
pointer is demoted without NON_OWN_REF and the graph kfunc argument is
rejected.

Also exercise a graph kptr loaded while a spin lock provides implicit RCU
protection. The pointer must be invalidated when the lock is released, which
guards the required ordering between non-owning-reference invalidation and
RCU demotion.

Update the existing fault-protected load test state description. The
post-unlock pointer no longer carries NON_OWN_REF, but remains readable
because the load is rewritten to use BPF_PROBE_MEM.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/clk/mvebu/common.h b/drivers/clk/mvebu/common.h
new file mode 100644
index 000000000..d1ab79b43
--- /dev/null
+++ b/drivers/clk/mvebu/common.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Marvell EBU SoC common clock handling
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
+ * Andrew Lunn <andrew@lunn.ch>
+ *
+ */
+
+#ifndef __CLK_MVEBU_COMMON_H_
+#define __CLK_MVEBU_COMMON_H_
+
+#include <linux/kernel.h>
+
+extern spinlock_t ctrl_gating_lock;
+
+struct device_node;
+
+struct coreclk_ratio {
+	int id;
+	const char *name;
+};
+
+struct coreclk_soc_desc {
+	u32 (*get_tclk_freq)(void __iomem *sar);
+	u32 (*get_cpu_freq)(void __iomem *sar);
+	void (*get_clk_ratio)(void __iomem *sar, int id, int *mult, int *div);
+	u32 (*get_refclk_freq)(void __iomem *sar);
+	bool (*is_sscg_enabled)(void __iomem *sar);
+	u32 (*fix_sscg_deviation)(u32 system_clk);
+	const struct coreclk_ratio *ratios;
+	int num_ratios;
+};
+
+struct clk_gating_soc_desc {
+	const char *name;
+	const char *parent;
+	int bit_idx;
+	unsigned long flags;
+};
+
+void __init mvebu_coreclk_setup(struct device_node *np,
+				const struct coreclk_soc_desc *desc);
+
+void __init mvebu_clk_gating_setup(struct device_node *np,
+				   const struct clk_gating_soc_desc *desc);
+
+/*
+ * This function is shared among the Kirkwood, Armada 370, Armada XP
+ * and Armada 375 SoC
+ */
+u32 kirkwood_fix_sscg_deviation(u32 system_clk);
+#endif