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, 56 insertions, 0 deletions

diff --git a/sound/soc/codecs/wm8750.h b/sound/soc/codecs/wm8750.h
new file mode 100644
index 000000000..325f58aa7
--- /dev/null
+++ b/sound/soc/codecs/wm8750.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2005 Openedhand Ltd.
+ *
+ * Author: Richard Purdie <richard@openedhand.com>
+ *
+ * Based on WM8753.h
+ */
+
+#ifndef _WM8750_H
+#define _WM8750_H
+
+/* WM8750 register space */
+
+#define WM8750_LINVOL    0x00
+#define WM8750_RINVOL    0x01
+#define WM8750_LOUT1V    0x02
+#define WM8750_ROUT1V    0x03
+#define WM8750_ADCDAC    0x05
+#define WM8750_IFACE     0x07
+#define WM8750_SRATE     0x08
+#define WM8750_LDAC      0x0a
+#define WM8750_RDAC      0x0b
+#define WM8750_BASS      0x0c
+#define WM8750_TREBLE    0x0d
+#define WM8750_RESET     0x0f
+#define WM8750_3D        0x10
+#define WM8750_ALC1      0x11
+#define WM8750_ALC2      0x12
+#define WM8750_ALC3      0x13
+#define WM8750_NGATE     0x14
+#define WM8750_LADC      0x15
+#define WM8750_RADC      0x16
+#define WM8750_ADCTL1    0x17
+#define WM8750_ADCTL2    0x18
+#define WM8750_PWR1      0x19
+#define WM8750_PWR2      0x1a
+#define WM8750_ADCTL3    0x1b
+#define WM8750_ADCIN     0x1f
+#define WM8750_LADCIN    0x20
+#define WM8750_RADCIN    0x21
+#define WM8750_LOUTM1    0x22
+#define WM8750_LOUTM2    0x23
+#define WM8750_ROUTM1    0x24
+#define WM8750_ROUTM2    0x25
+#define WM8750_MOUTM1    0x26
+#define WM8750_MOUTM2    0x27
+#define WM8750_LOUT2V    0x28
+#define WM8750_ROUT2V    0x29
+#define WM8750_MOUTV     0x2a
+
+#define WM8750_CACHE_REGNUM 0x2a
+
+#define WM8750_SYSCLK	0
+
+#endif