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, 36 insertions, 0 deletions

diff --git a/sound/soc/codecs/max98363.h b/sound/soc/codecs/max98363.h
new file mode 100644
index 000000000..2b6743d3a
--- /dev/null
+++ b/sound/soc/codecs/max98363.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (c) 2022 Analog Devices Inc. */
+
+#ifndef _MAX98363_H
+#define _MAX98363_H
+
+#define MAX98363_R2000_SW_RESET			0x2000
+#define MAX98363_R2001_INTR_RAW			0x2001
+#define MAX98363_R2003_INTR_STATE		0x2003
+#define MAX98363_R2005_INTR_FALG		0x2005
+#define MAX98363_R2007_INTR_EN			0x2007
+#define MAX98363_R2009_INTR_CLR			0x2009
+#define MAX98363_R2021_ERR_MON_CTRL		0x2021
+#define MAX98363_R2022_SPK_MON_THRESH		0x2022
+#define MAX98363_R2023_SPK_MON_DURATION		0x2023
+#define MAX98363_R2030_TONE_GEN_CFG		0x2030
+#define MAX98363_R203F_TONE_GEN_EN		0x203F
+#define MAX98363_R2040_AMP_VOL			0x2040
+#define MAX98363_R2041_AMP_GAIN			0x2041
+#define MAX98363_R2042_DSP_CFG			0x2042
+#define MAX98363_R21FF_REV_ID			0x21FF
+
+/* MAX98363_R2021_ERR_MON_CTRL */
+#define MAX98363_SPKMON_SHIFT			(3)
+#define MAX98363_CLOCK_MON_SHIFT		(0)
+
+/* MAX98363_R2042_DSP_CFG */
+#define MAX98363_AMP_DSP_CFG_RMP_SHIFT		(3)
+
+struct max98363_priv {
+	struct regmap *regmap;
+	struct sdw_slave *slave;
+	bool hw_init;
+	bool first_hw_init;
+};
+#endif