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, 25 insertions, 0 deletions

diff --git a/Documentation/admin-guide/sysctl/sunrpc.rst b/Documentation/admin-guide/sysctl/sunrpc.rst
new file mode 100644
index 000000000..09780a682
--- /dev/null
+++ b/Documentation/admin-guide/sysctl/sunrpc.rst
@@ -0,0 +1,25 @@
+===================================
+Documentation for /proc/sys/sunrpc/
+===================================
+
+kernel version 2.2.10
+
+Copyright (c) 1998, 1999,  Rik van Riel <riel@nl.linux.org>
+
+For general info and legal blurb, please look in index.rst.
+
+------------------------------------------------------------------------------
+
+This file contains the documentation for the sysctl files in
+/proc/sys/sunrpc and is valid for Linux kernel version 2.2.
+
+The files in this directory can be used to (re)set the debug
+flags of the SUN Remote Procedure Call (RPC) subsystem in
+the Linux kernel. This stuff is used for NFS, KNFSD and
+maybe a few other things as well.
+
+The files in there are used to control the debugging flags:
+rpc_debug, nfs_debug, nfsd_debug and nlm_debug.
+
+These flags are for kernel hackers only. You should read the
+source code in net/sunrpc/ for more information.