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, 18 insertions, 0 deletions

diff --git a/drivers/accel/amdxdna/Kconfig b/drivers/accel/amdxdna/Kconfig
new file mode 100644
index 000000000..f39d7a872
--- /dev/null
+++ b/drivers/accel/amdxdna/Kconfig
@@ -0,0 +1,18 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config DRM_ACCEL_AMDXDNA
+	tristate "AMD AI Engine"
+	depends on AMD_IOMMU
+	depends on DRM_ACCEL
+	depends on PCI && HAS_IOMEM
+	depends on X86_64
+	select DRM_SCHED
+	select DRM_GEM_SHMEM_HELPER
+	select FW_LOADER
+	select HMM_MIRROR
+	help
+	  Choose this option to enable support for NPU integrated into AMD
+	  client CPUs like AMD Ryzen AI 300 Series. AMD NPU can be used to
+	  accelerate machine learning applications.
+
+	  If "M" is selected, the driver module will be amdxdna.