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, 63 insertions, 0 deletions

diff --git a/sound/soc/codecs/max98371.h b/sound/soc/codecs/max98371.h
new file mode 100644
index 000000000..63d9a9de3
--- /dev/null
+++ b/sound/soc/codecs/max98371.h
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * max98371.h -- MAX98371 ALSA SoC Audio driver
+ *
+ * Copyright 2011-2012 Maxim Integrated Products
+ */
+
+#ifndef _MAX98371_H
+#define _MAX98371_H
+
+#define MAX98371_IRQ_CLEAR1			0x01
+#define MAX98371_IRQ_CLEAR2			0x02
+#define MAX98371_IRQ_CLEAR3			0x03
+#define MAX98371_DAI_CLK			0x10
+#define MAX98371_DAI_BSEL_MASK			0xF
+#define MAX98371_DAI_BSEL_32			2
+#define MAX98371_DAI_BSEL_48			3
+#define MAX98371_DAI_BSEL_64			4
+#define MAX98371_SPK_SR				0x11
+#define MAX98371_SPK_SR_MASK			0xF
+#define MAX98371_SPK_SR_32			6
+#define MAX98371_SPK_SR_44			7
+#define MAX98371_SPK_SR_48			8
+#define MAX98371_SPK_SR_88			10
+#define MAX98371_SPK_SR_96			11
+#define MAX98371_DAI_CHANNEL			0x15
+#define MAX98371_CHANNEL_MASK			0x3
+#define MAX98371_MONOMIX_SRC			0x18
+#define MAX98371_MONOMIX_CFG			0x19
+#define MAX98371_HPF				0x1C
+#define MAX98371_MONOMIX_SRC_MASK		0xFF
+#define MONOMIX_RX_0_1				((0x1)<<(4))
+#define M98371_DAI_CHANNEL_I2S			0x3
+#define MAX98371_DIGITAL_GAIN			0x2D
+#define MAX98371_DIGITAL_GAIN_WIDTH		0x7
+#define MAX98371_GAIN				0x2E
+#define MAX98371_GAIN_SHIFT			0x4
+#define MAX98371_GAIN_WIDTH			0x4
+#define MAX98371_DHT_MAX_WIDTH			4
+#define MAX98371_FMT				0x14
+#define MAX98371_CHANSZ_WIDTH			6
+#define MAX98371_FMT_MASK		        ((0x3)<<(MAX98371_CHANSZ_WIDTH))
+#define MAX98371_FMT_MODE_MASK		        ((0x7)<<(3))
+#define MAX98371_DAI_LEFT		        ((0x1)<<(3))
+#define MAX98371_DAI_RIGHT		        ((0x2)<<(3))
+#define MAX98371_DAI_CHANSZ_16                  ((1)<<(MAX98371_CHANSZ_WIDTH))
+#define MAX98371_DAI_CHANSZ_24                  ((2)<<(MAX98371_CHANSZ_WIDTH))
+#define MAX98371_DAI_CHANSZ_32                  ((3)<<(MAX98371_CHANSZ_WIDTH))
+#define MAX98371_DHT  0x32
+#define MAX98371_DHT_STEP			0x3
+#define MAX98371_DHT_GAIN			0x31
+#define MAX98371_DHT_GAIN_WIDTH			0x4
+#define MAX98371_DHT_ROT_WIDTH			0x4
+#define MAX98371_SPK_ENABLE			0x4A
+#define MAX98371_GLOBAL_ENABLE			0x50
+#define MAX98371_SOFT_RESET			0x51
+#define MAX98371_VERSION			0xFF
+
+
+struct max98371_priv {
+	struct regmap *regmap;
+};
+#endif