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, 82 insertions, 0 deletions

diff --git a/sound/soc/codecs/wm8978.h b/sound/soc/codecs/wm8978.h
new file mode 100644
index 000000000..e1986dcec
--- /dev/null
+++ b/sound/soc/codecs/wm8978.h
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * wm8978.h		--  codec driver for WM8978
+ *
+ * Copyright 2009 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ */
+
+#ifndef __WM8978_H__
+#define __WM8978_H__
+
+/*
+ * Register values.
+ */
+#define WM8978_RESET				0x00
+#define WM8978_POWER_MANAGEMENT_1		0x01
+#define WM8978_POWER_MANAGEMENT_2		0x02
+#define WM8978_POWER_MANAGEMENT_3		0x03
+#define WM8978_AUDIO_INTERFACE			0x04
+#define WM8978_COMPANDING_CONTROL		0x05
+#define WM8978_CLOCKING				0x06
+#define WM8978_ADDITIONAL_CONTROL		0x07
+#define WM8978_GPIO_CONTROL			0x08
+#define WM8978_JACK_DETECT_CONTROL_1		0x09
+#define WM8978_DAC_CONTROL			0x0A
+#define WM8978_LEFT_DAC_DIGITAL_VOLUME		0x0B
+#define WM8978_RIGHT_DAC_DIGITAL_VOLUME		0x0C
+#define WM8978_JACK_DETECT_CONTROL_2		0x0D
+#define WM8978_ADC_CONTROL			0x0E
+#define WM8978_LEFT_ADC_DIGITAL_VOLUME		0x0F
+#define WM8978_RIGHT_ADC_DIGITAL_VOLUME		0x10
+#define WM8978_EQ1				0x12
+#define WM8978_EQ2				0x13
+#define WM8978_EQ3				0x14
+#define WM8978_EQ4				0x15
+#define WM8978_EQ5				0x16
+#define WM8978_DAC_LIMITER_1			0x18
+#define WM8978_DAC_LIMITER_2			0x19
+#define WM8978_NOTCH_FILTER_1			0x1b
+#define WM8978_NOTCH_FILTER_2			0x1c
+#define WM8978_NOTCH_FILTER_3			0x1d
+#define WM8978_NOTCH_FILTER_4			0x1e
+#define WM8978_ALC_CONTROL_1			0x20
+#define WM8978_ALC_CONTROL_2			0x21
+#define WM8978_ALC_CONTROL_3			0x22
+#define WM8978_NOISE_GATE			0x23
+#define WM8978_PLL_N				0x24
+#define WM8978_PLL_K1				0x25
+#define WM8978_PLL_K2				0x26
+#define WM8978_PLL_K3				0x27
+#define WM8978_3D_CONTROL			0x29
+#define WM8978_BEEP_CONTROL			0x2b
+#define WM8978_INPUT_CONTROL			0x2c
+#define WM8978_LEFT_INP_PGA_CONTROL		0x2d
+#define WM8978_RIGHT_INP_PGA_CONTROL		0x2e
+#define WM8978_LEFT_ADC_BOOST_CONTROL		0x2f
+#define WM8978_RIGHT_ADC_BOOST_CONTROL		0x30
+#define WM8978_OUTPUT_CONTROL			0x31
+#define WM8978_LEFT_MIXER_CONTROL		0x32
+#define WM8978_RIGHT_MIXER_CONTROL		0x33
+#define WM8978_LOUT1_HP_CONTROL			0x34
+#define WM8978_ROUT1_HP_CONTROL			0x35
+#define WM8978_LOUT2_SPK_CONTROL		0x36
+#define WM8978_ROUT2_SPK_CONTROL		0x37
+#define WM8978_OUT3_MIXER_CONTROL		0x38
+#define WM8978_OUT4_MIXER_CONTROL		0x39
+
+#define WM8978_MAX_REGISTER			0x39
+
+#define WM8978_CACHEREGNUM			58
+
+/* Clock divider Id's */
+enum wm8978_clk_id {
+	WM8978_OPCLKRATE,
+	WM8978_BCLKDIV,
+};
+
+enum wm8978_sysclk_src {
+	WM8978_MCLK = 0,
+	WM8978_PLL,
+};
+
+#endif	/* __WM8978_H__ */