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, 48 insertions, 0 deletions

diff --git a/Documentation/driver-api/dmaengine/index.rst b/Documentation/driver-api/dmaengine/index.rst
new file mode 100644
index 000000000..e74677c66
--- /dev/null
+++ b/Documentation/driver-api/dmaengine/index.rst
@@ -0,0 +1,48 @@
+=======================
+DMAEngine documentation
+=======================
+
+DMAEngine documentation provides documents for various aspects of DMAEngine
+framework.
+
+DMAEngine development documentation
+-----------------------------------
+
+This book helps with DMAengine internal APIs and guide for DMAEngine device
+driver writers.
+
+.. toctree::
+   :maxdepth: 1
+
+   provider
+
+DMAEngine client documentation
+------------------------------
+
+This book is a guide to device driver writers on how to use the Slave-DMA
+API of the DMAEngine. This is applicable only for slave DMA usage only.
+
+.. toctree::
+   :maxdepth: 1
+
+   client
+
+DMA Test documentation
+----------------------
+
+This book introduces how to test DMA drivers using dmatest module.
+
+.. toctree::
+   :maxdepth: 1
+
+   dmatest
+
+PXA DMA documentation
+----------------------
+
+This book adds some notes about PXA DMA
+
+.. toctree::
+   :maxdepth: 1
+
+   pxa_dma