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, 36 insertions, 0 deletions

diff --git a/sound/soc/codecs/wm8711.h b/sound/soc/codecs/wm8711.h
new file mode 100644
index 000000000..487a9f34d
--- /dev/null
+++ b/sound/soc/codecs/wm8711.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * wm8711.h  --  WM8711 Soc Audio driver
+ *
+ * Copyright 2006 Wolfson Microelectronics
+ *
+ * Author: Mike Arthur <linux@wolfsonmicro.com>
+ *
+ * Based on wm8731.h
+ */
+
+#ifndef _WM8711_H
+#define _WM8711_H
+
+/* WM8711 register space */
+
+#define WM8711_LOUT1V   0x02
+#define WM8711_ROUT1V   0x03
+#define WM8711_APANA    0x04
+#define WM8711_APDIGI   0x05
+#define WM8711_PWR      0x06
+#define WM8711_IFACE    0x07
+#define WM8711_SRATE    0x08
+#define WM8711_ACTIVE   0x09
+#define WM8711_RESET	0x0f
+
+#define WM8711_CACHEREGNUM 	8
+
+#define WM8711_SYSCLK	0
+#define WM8711_DAI		0
+
+struct wm8711_setup_data {
+	unsigned short i2c_address;
+};
+
+#endif