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, 47 insertions, 0 deletions

diff --git a/sound/hda/controllers/intel.h b/sound/hda/controllers/intel.h
new file mode 100644
index 000000000..4efb3b0fc
--- /dev/null
+++ b/sound/hda/controllers/intel.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ */
+#ifndef __SOUND_HDA_INTEL_H
+#define __SOUND_HDA_INTEL_H
+
+#include "hda_controller.h"
+
+struct hda_intel {
+	struct azx chip;
+
+	/* sync probing */
+	struct completion probe_wait;
+	struct delayed_work probe_work;
+
+	/* card list (for power_save trigger) */
+	struct list_head list;
+
+	/* extra flags */
+	unsigned int irq_pending_warned:1;
+	unsigned int probe_continued:1;
+	unsigned int runtime_pm_disabled:1;
+
+	/* vga_switcheroo setup */
+	unsigned int use_vga_switcheroo:1;
+	unsigned int vga_switcheroo_registered:1;
+	unsigned int init_failed:1; /* delayed init failed */
+	unsigned int freed:1; /* resources already released */
+
+	bool need_i915_power:1; /* the hda controller needs i915 power */
+
+	int probe_retry;	/* being probe-retry */
+};
+
+struct hda_intel_stream {
+	struct azx_dev azx_dev;
+
+	/* for pending irqs */
+	struct hda_intel *hda;
+	struct work_struct irq_pending_work;
+	bool irq_pending;
+};
+
+#define azx_dev_to_istream(azx_dev) \
+	container_of(azx_dev, struct hda_intel_stream, azx_dev)
+
+#endif