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, 54 insertions, 0 deletions

diff --git a/drivers/pinctrl/vt8500/Kconfig b/drivers/pinctrl/vt8500/Kconfig
new file mode 100644
index 000000000..1a40c153a
--- /dev/null
+++ b/drivers/pinctrl/vt8500/Kconfig
@@ -0,0 +1,54 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# VIA/Wondermedia PINCTRL drivers
+#
+
+if ARCH_VT8500 || COMPILE_TEST
+
+config PINCTRL_WMT
+	bool
+	select PINMUX
+	select GENERIC_PINCONF
+	select GPIOLIB
+
+config PINCTRL_VT8500
+	bool "VIA VT8500 pin controller driver"
+	depends on ARCH_WM8505 || COMPILE_TEST
+	select PINCTRL_WMT
+	help
+	  Say yes here to support the gpio/pin control module on
+	  VIA VT8500 SoCs.
+
+config PINCTRL_WM8505
+	bool "Wondermedia WM8505 pin controller driver"
+	depends on ARCH_WM8505 || COMPILE_TEST
+	select PINCTRL_WMT
+	help
+	  Say yes here to support the gpio/pin control module on
+	  Wondermedia WM8505 SoCs.
+
+config PINCTRL_WM8650
+	bool "Wondermedia WM8650 pin controller driver"
+	depends on ARCH_WM8505 || COMPILE_TEST
+	select PINCTRL_WMT
+	help
+	  Say yes here to support the gpio/pin control module on
+	  Wondermedia WM8650 SoCs.
+
+config PINCTRL_WM8750
+	bool "Wondermedia WM8750 pin controller driver"
+	depends on ARCH_WM8750 || COMPILE_TEST
+	select PINCTRL_WMT
+	help
+	  Say yes here to support the gpio/pin control module on
+	  Wondermedia WM8750 SoCs.
+
+config PINCTRL_WM8850
+	bool "Wondermedia WM8850 pin controller driver"
+	depends on ARCH_WM8850 || COMPILE_TEST
+	select PINCTRL_WMT
+	help
+	  Say yes here to support the gpio/pin control module on
+	  Wondermedia WM8850 SoCs.
+
+endif