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, 48 insertions, 0 deletions

diff --git a/sound/soc/codecs/wm8770.h b/sound/soc/codecs/wm8770.h
new file mode 100644
index 000000000..e0a3f5a14
--- /dev/null
+++ b/sound/soc/codecs/wm8770.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * wm8770.h  --  WM8770 ASoC driver
+ *
+ * Copyright 2010 Wolfson Microelectronics plc
+ *
+ * Author: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
+ */
+
+#ifndef _WM8770_H
+#define _WM8770_H
+
+/* Registers */
+#define WM8770_VOUT1LVOL                0
+#define WM8770_VOUT1RVOL                0x1
+#define WM8770_VOUT2LVOL                0x2
+#define WM8770_VOUT2RVOL                0x3
+#define WM8770_VOUT3LVOL                0x4
+#define WM8770_VOUT3RVOL                0x5
+#define WM8770_VOUT4LVOL                0x6
+#define WM8770_VOUT4RVOL                0x7
+#define WM8770_MSALGVOL                 0x8
+#define WM8770_DAC1LVOL                 0x9
+#define WM8770_DAC1RVOL                 0xa
+#define WM8770_DAC2LVOL                 0xb
+#define WM8770_DAC2RVOL                 0xc
+#define WM8770_DAC3LVOL                 0xd
+#define WM8770_DAC3RVOL                 0xe
+#define WM8770_DAC4LVOL                 0xf
+#define WM8770_DAC4RVOL                 0x10
+#define WM8770_MSDIGVOL                 0x11
+#define WM8770_DACPHASE                 0x12
+#define WM8770_DACCTRL1                 0x13
+#define WM8770_DACMUTE                  0x14
+#define WM8770_DACCTRL2                 0x15
+#define WM8770_IFACECTRL                0x16
+#define WM8770_MSTRCTRL                 0x17
+#define WM8770_PWDNCTRL                 0x18
+#define WM8770_ADCLCTRL                 0x19
+#define WM8770_ADCRCTRL                 0x1a
+#define WM8770_ADCMUX                   0x1b
+#define WM8770_OUTMUX1                  0x1c
+#define WM8770_OUTMUX2                  0x1d
+#define WM8770_RESET                    0x31
+
+#define WM8770_CACHEREGNUM 0x20
+
+#endif