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, 41 insertions, 0 deletions

diff --git a/drivers/clk/qcom/clk-krait.h b/drivers/clk/qcom/clk-krait.h
new file mode 100644
index 000000000..f930538c5
--- /dev/null
+++ b/drivers/clk/qcom/clk-krait.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __QCOM_CLK_KRAIT_H
+#define __QCOM_CLK_KRAIT_H
+
+#include <linux/clk-provider.h>
+
+struct krait_mux_clk {
+	unsigned int	*parent_map;
+	u32		offset;
+	u32		mask;
+	u32		shift;
+	u32		en_mask;
+	bool		lpl;
+	u8		safe_sel;
+	u8		old_index;
+	bool		reparent;
+	bool		disable_sec_src_gating;
+
+	struct clk_hw	hw;
+	struct notifier_block   clk_nb;
+};
+
+#define to_krait_mux_clk(_hw) container_of(_hw, struct krait_mux_clk, hw)
+
+extern const struct clk_ops krait_mux_clk_ops;
+
+struct krait_div2_clk {
+	u32		offset;
+	u8		width;
+	u32		shift;
+	bool		lpl;
+
+	struct clk_hw	hw;
+};
+
+#define to_krait_div2_clk(_hw) container_of(_hw, struct krait_div2_clk, hw)
+
+extern const struct clk_ops krait_div2_clk_ops;
+
+#endif