Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEADgrafted

Changes:

Make expedited grace periods expedite normal RCU callbacks

Miscellaneous fixes:
 * Improve diagnostic output with character task states.
 * Mark accesses to inform KCSAN of concurrency design.
 * Move from kmalloc() to kmalloc_obj().
 * Documentation updates.
 * Improve handling of RCU deferred quiescent states.
 * Clean up unused function arguments and structure fields.
 * Reduce show_rcu_gp_kthreads() stack space.

Tasks RCU updates:
 * Clean up after SRCU re-implementation of Tasks Trace RCU.
 * Mark accesses to inform KCSAN of concurrency design.
 * Add ->lazy_timer status to diagnostic output.
 * Remove an unnecessary memory barrier.
 * Fix a data race, courtesy of KCSAN.
 * Documentation updates.
 * Convert cond_resched_tasks_rcu_qs() from macro to static inline
   function.

SRCU updates:
 * Add Rust helpers for SRCU.
 * Avoid losing queued work at cleanup_srcu_struct() time.

Torture-test updates:
 * Preparation work for immediate RCU priority deboosting.
 * Test RCU readers from real interrupt handlers (as opposed to softirq).
 * Simplify code through use of cpumask_next_wrap().
 * Improve diagnostic output with character task states.
 * Add rcutorture.nwriters parameter to allow lightweight stall testing,
   and rcutorture.stall_only to make doing so easier.
 * Test an RCU Tasks Trace grace period implying an RCU grace period.
 * Make RCU Tasks Trace torturing track reader batches.
 * Fix a data race, courtesy of KCSAN.
 * Plug a shuffle_tmp_mask memory leak on kthread spawn failure.

1 files changed, 59 insertions, 0 deletions

diff --git a/Documentation/process/coding-assistants.rst b/Documentation/process/coding-assistants.rst
new file mode 100644
index 000000000..899f4459c
--- /dev/null
+++ b/Documentation/process/coding-assistants.rst
@@ -0,0 +1,59 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. _coding_assistants:
+
+AI Coding Assistants
+++++++++++++++++++++
+
+This document provides guidance for AI tools and developers using AI
+assistance when contributing to the Linux kernel.
+
+AI tools helping with Linux kernel development should follow the standard
+kernel development process:
+
+* Documentation/process/development-process.rst
+* Documentation/process/coding-style.rst
+* Documentation/process/submitting-patches.rst
+
+Licensing and Legal Requirements
+================================
+
+All contributions must comply with the kernel's licensing requirements:
+
+* All code must be compatible with GPL-2.0-only
+* Use appropriate SPDX license identifiers
+* See Documentation/process/license-rules.rst for details
+
+Signed-off-by and Developer Certificate of Origin
+=================================================
+
+AI agents MUST NOT add Signed-off-by tags. Only humans can legally
+certify the Developer Certificate of Origin (DCO). The human submitter
+is responsible for:
+
+* Reviewing all AI-generated code
+* Ensuring compliance with licensing requirements
+* Adding their own Signed-off-by tag to certify the DCO
+* Taking full responsibility for the contribution
+
+Attribution
+===========
+
+When AI tools contribute to kernel development, proper attribution
+helps track the evolving role of AI in the development process.
+Contributions should include an Assisted-by tag in the following format::
+
+  Assisted-by: AGENT_NAME:MODEL_VERSION [TOOL1] [TOOL2]
+
+Where:
+
+* ``AGENT_NAME`` is the name of the AI tool or framework
+* ``MODEL_VERSION`` is the specific model version used
+* ``[TOOL1] [TOOL2]`` are optional specialized analysis tools used
+  (e.g., coccinelle, sparse, smatch, clang-tidy)
+
+Basic development tools (git, gcc, make, editors) should not be listed.
+
+Example::
+
+  Assisted-by: Claude:claude-3-opus coccinelle sparse