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, 22 insertions, 0 deletions

diff --git a/drivers/input/rmi4/Makefile b/drivers/input/rmi4/Makefile
new file mode 100644
index 000000000..35ae29f72
--- /dev/null
+++ b/drivers/input/rmi4/Makefile
@@ -0,0 +1,22 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_RMI4_CORE) += rmi_core.o
+rmi_core-y := rmi_bus.o rmi_driver.o rmi_f01.o
+
+rmi_core-$(CONFIG_RMI4_2D_SENSOR) += rmi_2d_sensor.o
+
+# Function drivers
+rmi_core-$(CONFIG_RMI4_F03) += rmi_f03.o
+rmi_core-$(CONFIG_RMI4_F11) += rmi_f11.o
+rmi_core-$(CONFIG_RMI4_F12) += rmi_f12.o
+rmi_core-$(CONFIG_RMI4_F1A) += rmi_f1a.o
+rmi_core-$(CONFIG_RMI4_F21) += rmi_f21.o
+rmi_core-$(CONFIG_RMI4_F30) += rmi_f30.o
+rmi_core-$(CONFIG_RMI4_F34) += rmi_f34.o rmi_f34v7.o
+rmi_core-$(CONFIG_RMI4_F3A) += rmi_f3a.o
+rmi_core-$(CONFIG_RMI4_F54) += rmi_f54.o
+rmi_core-$(CONFIG_RMI4_F55) += rmi_f55.o
+
+# Transports
+obj-$(CONFIG_RMI4_I2C) += rmi_i2c.o
+obj-$(CONFIG_RMI4_SPI) += rmi_spi.o
+obj-$(CONFIG_RMI4_SMB) += rmi_smbus.o