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, 109 insertions, 0 deletions

diff --git a/sound/soc/codecs/rt712-sdca-dmic.h b/sound/soc/codecs/rt712-sdca-dmic.h
new file mode 100644
index 000000000..2f08e58ed
--- /dev/null
+++ b/sound/soc/codecs/rt712-sdca-dmic.h
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * rt712-sdca-dmic.h -- RT712 SDCA DMIC ALSA SoC audio driver header
+ *
+ * Copyright(c) 2023 Realtek Semiconductor Corp.
+ */
+
+#ifndef __RT712_SDW_DMIC_H__
+#define __RT712_SDW_DMIC_H__
+
+#include <linux/regmap.h>
+#include <linux/soundwire/sdw_registers.h>
+
+struct  rt712_sdca_dmic_priv {
+	struct regmap *regmap;
+	struct regmap *mbq_regmap;
+	struct snd_soc_component *component;
+	struct sdw_slave *slave;
+	struct sdw_bus_params params;
+	bool hw_init;
+	bool first_hw_init;
+	bool fu1e_dapm_mute;
+	bool fu1e_mixer_mute[4];
+};
+
+struct rt712_sdca_dmic_kctrl_priv {
+	unsigned int reg_base;
+	unsigned int count;
+	unsigned int max;
+	unsigned int invert;
+};
+
+/* SDCA (Channel) */
+#define CH_01	0x01
+#define CH_02	0x02
+#define CH_03	0x03
+#define CH_04	0x04
+
+/* must stay sorted by register address, regcache_lookup_reg() does a bsearch() */
+static const struct reg_default rt712_sdca_dmic_reg_defaults[] = {
+	{ 0x201a, 0x00 },
+	{ 0x201b, 0x00 },
+	{ 0x201c, 0x00 },
+	{ 0x201d, 0x00 },
+	{ 0x201e, 0x00 },
+	{ 0x201f, 0x00 },
+	{ 0x2029, 0x00 },
+	{ 0x202a, 0x00 },
+	{ 0x202d, 0x00 },
+	{ 0x202e, 0x00 },
+	{ 0x202f, 0x00 },
+	{ 0x2030, 0x00 },
+	{ 0x2031, 0x00 },
+	{ 0x2032, 0x00 },
+	{ 0x2033, 0x00 },
+	{ 0x2034, 0x00 },
+	{ 0x2230, 0x00 },
+	{ 0x2231, 0x2f },
+	{ 0x2232, 0x80 },
+	{ 0x2f01, 0x00 },
+	{ 0x2f02, 0x09 },
+	{ 0x2f03, 0x00 },
+	{ 0x2f04, 0x00 },
+	{ 0x2f05, 0x0b },
+	{ 0x2f06, 0x01 },
+	{ 0x2f08, 0x00 },
+	{ 0x2f09, 0x00 },
+	{ 0x2f0a, 0x01 },
+	{ 0x2f35, 0x02 },
+	{ 0x2f36, 0xcf },
+	{ 0x2f52, 0x08 },
+	{ 0x2f58, 0x07 },
+	{ 0x2f59, 0x07 },
+	{ 0x3201, 0x01 },
+	{ 0x320c, 0x00 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_MUTE, CH_01), 0x01 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_MUTE, CH_02), 0x01 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_MUTE, CH_03), 0x01 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_MUTE, CH_04), 0x01 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_CS1C, RT712_SDCA_CTL_SAMPLE_FREQ_INDEX, 0), 0x09 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_CS1F, RT712_SDCA_CTL_SAMPLE_FREQ_INDEX, 0), 0x09 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_IT26, RT712_SDCA_CTL_VENDOR_DEF, 0), 0x00 },
+};
+
+/* must stay sorted by register address, regcache_lookup_reg() does a bsearch() */
+static const struct reg_default rt712_sdca_dmic_mbq_defaults[] = {
+	{ 0x0590001e, 0x0020 },
+	{ 0x06100000, 0x0010 },
+	{ 0x06100006, 0x0055 },
+	{ 0x06100010, 0x2630 },
+	{ 0x06100011, 0x152f },
+	{ 0x06100013, 0x0102 },
+	{ 0x06100015, 0x2219 },
+	{ 0x06100018, 0x0102 },
+	{ 0x06100026, 0x2c29 },
+	{ 0x06100027, 0x2d2b },
+	{ 0x0610002b, 0x2a32 },
+	{ 0x0610002f, 0x3355 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_PLATFORM_FU15, RT712_SDCA_CTL_FU_CH_GAIN, CH_01), 0x0000 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_PLATFORM_FU15, RT712_SDCA_CTL_FU_CH_GAIN, CH_02), 0x0000 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_PLATFORM_FU15, RT712_SDCA_CTL_FU_CH_GAIN, CH_03), 0x0000 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_PLATFORM_FU15, RT712_SDCA_CTL_FU_CH_GAIN, CH_04), 0x0000 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_VOLUME, CH_01), 0x0000 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_VOLUME, CH_02), 0x0000 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_VOLUME, CH_03), 0x0000 },
+	{ SDW_SDCA_CTL(FUNC_NUM_MIC_ARRAY, RT712_SDCA_ENT_USER_FU1E, RT712_SDCA_CTL_FU_VOLUME, CH_04), 0x0000 },
+};
+
+#endif /* __RT712_SDW_DMIC_H__ */