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, 32 insertions, 0 deletions

diff --git a/rust/helpers/device.c b/rust/helpers/device.c
new file mode 100644
index 000000000..3be4ee590
--- /dev/null
+++ b/rust/helpers/device.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/device.h>
+
+__rust_helper int rust_helper_devm_add_action(struct device *dev,
+					      void (*action)(void *),
+					      void *data)
+{
+	return devm_add_action(dev, action, data);
+}
+
+__rust_helper int rust_helper_devm_add_action_or_reset(struct device *dev,
+						       void (*action)(void *),
+						       void *data)
+{
+	return devm_add_action_or_reset(dev, action, data);
+}
+
+__rust_helper void *rust_helper_dev_get_drvdata(const struct device *dev)
+{
+	return dev_get_drvdata(dev);
+}
+
+__rust_helper void rust_helper_dev_set_drvdata(struct device *dev, void *data)
+{
+	dev_set_drvdata(dev, data);
+}
+
+__rust_helper const char *rust_helper_dev_name(const struct device *dev)
+{
+	return dev_name(dev);
+}