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, 72 insertions, 0 deletions

diff --git a/drivers/pinctrl/mediatek/pinctrl-paris.h b/drivers/pinctrl/mediatek/pinctrl-paris.h
new file mode 100644
index 000000000..d8c182266
--- /dev/null
+++ b/drivers/pinctrl/mediatek/pinctrl-paris.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 MediaTek Inc.
+ *
+ * Author: Sean Wang <sean.wang@mediatek.com>
+ *	   Zhiyong Tao <zhiyong.tao@mediatek.com>
+ *	   Hongzhou.Yang <hongzhou.yang@mediatek.com>
+ */
+#ifndef __PINCTRL_PARIS_H
+#define __PINCTRL_PARIS_H
+
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinconf-generic.h>
+
+#include "../core.h"
+#include "../pinconf.h"
+#include "../pinctrl-utils.h"
+#include "../pinmux.h"
+#include "mtk-eint.h"
+#include "pinctrl-mtk-common-v2.h"
+
+#define MTK_RANGE(_a)		{ .range = (_a), .nranges = ARRAY_SIZE(_a), }
+
+#define MTK_EINT_FUNCTION(_eintmux, _eintnum)				\
+	{							\
+		.eint_m = _eintmux,					\
+		.eint_n = _eintnum,					\
+	}
+
+#define MTK_FUNCTION(_val, _name)				\
+	{							\
+		.muxval = _val,					\
+		.name = _name,					\
+	}
+
+#define MTK_PIN(_number, _name, _eint, _drv_n, ...) {	\
+		.number = _number,			\
+		.name = _name,				\
+		.eint = _eint,				\
+		.drv_n = _drv_n,			\
+		.funcs = (struct mtk_func_desc[]){	\
+			__VA_ARGS__, { } },				\
+	}
+
+#define MTK_EINT_PIN(_number, _instance, _index, _debounce) {	\
+		.number = _number,				\
+		.instance = _instance,				\
+		.index = _index,				\
+		.debounce = _debounce,				\
+	}
+
+#define PINCTRL_PIN_GROUP(_name_, id)							\
+	{										\
+		.grp = PINCTRL_PINGROUP(_name_,id##_pins, ARRAY_SIZE(id##_pins)),	\
+		.data = id##_funcs,							\
+	}
+
+int mtk_paris_pinctrl_probe(struct platform_device *pdev);
+
+ssize_t mtk_pctrl_show_one_pin(struct mtk_pinctrl *hw,
+	unsigned int gpio, char *buf, unsigned int bufLen);
+
+extern const struct dev_pm_ops mtk_paris_pinctrl_pm_ops;
+
+#endif /* __PINCTRL_PARIS_H */