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, 131 insertions, 0 deletions

diff --git a/drivers/clk/spear/clk.h b/drivers/clk/spear/clk.h
new file mode 100644
index 000000000..3d580d1bd
--- /dev/null
+++ b/drivers/clk/spear/clk.h
@@ -0,0 +1,131 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Clock framework definitions for SPEAr platform
+ *
+ * Copyright (C) 2012 ST Microelectronics
+ * Viresh Kumar <vireshk@kernel.org>
+ */
+
+#ifndef __SPEAR_CLK_H
+#define __SPEAR_CLK_H
+
+#include <linux/clk-provider.h>
+#include <linux/spinlock_types.h>
+#include <linux/types.h>
+
+/* Auxiliary Synth clk */
+/* Default masks */
+#define AUX_EQ_SEL_SHIFT	30
+#define AUX_EQ_SEL_MASK		1
+#define AUX_EQ1_SEL		0
+#define AUX_EQ2_SEL		1
+#define AUX_XSCALE_SHIFT	16
+#define AUX_XSCALE_MASK		0xFFF
+#define AUX_YSCALE_SHIFT	0
+#define AUX_YSCALE_MASK		0xFFF
+#define AUX_SYNT_ENB		31
+
+struct aux_clk_masks {
+	u32 eq_sel_mask;
+	u32 eq_sel_shift;
+	u32 eq1_mask;
+	u32 eq2_mask;
+	u32 xscale_sel_mask;
+	u32 xscale_sel_shift;
+	u32 yscale_sel_mask;
+	u32 yscale_sel_shift;
+	u32 enable_bit;
+};
+
+struct aux_rate_tbl {
+	u16 xscale;
+	u16 yscale;
+	u8 eq;
+};
+
+struct clk_aux {
+	struct			clk_hw hw;
+	void __iomem		*reg;
+	const struct aux_clk_masks *masks;
+	struct aux_rate_tbl	*rtbl;
+	u8			rtbl_cnt;
+	spinlock_t		*lock;
+};
+
+/* Fractional Synth clk */
+struct frac_rate_tbl {
+	u32 div;
+};
+
+struct clk_frac {
+	struct			clk_hw hw;
+	void __iomem		*reg;
+	struct frac_rate_tbl	*rtbl;
+	u8			rtbl_cnt;
+	spinlock_t		*lock;
+};
+
+/* GPT clk */
+struct gpt_rate_tbl {
+	u16 mscale;
+	u16 nscale;
+};
+
+struct clk_gpt {
+	struct			clk_hw hw;
+	void __iomem		*reg;
+	struct gpt_rate_tbl	*rtbl;
+	u8			rtbl_cnt;
+	spinlock_t		*lock;
+};
+
+/* VCO-PLL clk */
+struct pll_rate_tbl {
+	u8 mode;
+	u16 m;
+	u8 n;
+	u8 p;
+};
+
+struct clk_vco {
+	struct			clk_hw hw;
+	void __iomem		*mode_reg;
+	void __iomem		*cfg_reg;
+	struct pll_rate_tbl	*rtbl;
+	u8			rtbl_cnt;
+	spinlock_t		*lock;
+};
+
+struct clk_pll {
+	struct			clk_hw hw;
+	struct clk_vco		*vco;
+	const char		*parent[1];
+	spinlock_t		*lock;
+};
+
+typedef unsigned long (*clk_calc_rate)(struct clk_hw *hw, unsigned long prate,
+		int index);
+
+/* clk register routines */
+struct clk *clk_register_aux(const char *aux_name, const char *gate_name,
+		const char *parent_name, unsigned long flags, void __iomem *reg,
+		const struct aux_clk_masks *masks, struct aux_rate_tbl *rtbl,
+		u8 rtbl_cnt, spinlock_t *lock, struct clk **gate_clk);
+struct clk *clk_register_frac(const char *name, const char *parent_name,
+		unsigned long flags, void __iomem *reg,
+		struct frac_rate_tbl *rtbl, u8 rtbl_cnt, spinlock_t *lock);
+struct clk *clk_register_gpt(const char *name, const char *parent_name, unsigned
+		long flags, void __iomem *reg, struct gpt_rate_tbl *rtbl, u8
+		rtbl_cnt, spinlock_t *lock);
+struct clk *clk_register_vco_pll(const char *vco_name, const char *pll_name,
+		const char *vco_gate_name, const char *parent_name,
+		unsigned long flags, void __iomem *mode_reg, void __iomem
+		*cfg_reg, struct pll_rate_tbl *rtbl, u8 rtbl_cnt,
+		spinlock_t *lock, struct clk **pll_clk,
+		struct clk **vco_gate_clk);
+
+long clk_round_rate_index(struct clk_hw *hw, unsigned long drate,
+		unsigned long parent_rate, clk_calc_rate calc_rate, u8 rtbl_cnt,
+		int *index);
+
+#endif /* __SPEAR_CLK_H */