bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 26 insertions, 0 deletions

diff --git a/Documentation/gpu/rfc/index.rst b/Documentation/gpu/rfc/index.rst
new file mode 100644
index 000000000..26a7ebe6f
--- /dev/null
+++ b/Documentation/gpu/rfc/index.rst
@@ -0,0 +1,26 @@
+===============
+GPU RFC Section
+===============
+
+For complex work, especially new uapi, it is often good to nail the high level
+design issues before getting lost in the code details. This section is meant to
+host such documentation:
+
+* Each RFC should be a section in this file, explaining the goal and main design
+  considerations. Especially for uapi make sure you Cc: all relevant project
+  mailing lists and involved people outside of dri-devel.
+
+* For uapi structures add a file to this directory with and then pull the
+  kerneldoc in like with real uapi headers.
+
+* Once the code has landed move all the documentation to the right places in
+  the main core, helper or driver sections.
+
+.. toctree::
+
+   gpusvm
+   i915_gem_lmem
+   i915_scheduler
+   i915_small_bar
+   i915_vm_bind
+   color_pipeline