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/arch/alpha/lib/strcpy.S b/arch/alpha/lib/strcpy.S
new file mode 100644
index 000000000..d8773ba77
--- /dev/null
+++ b/arch/alpha/lib/strcpy.S
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * arch/alpha/lib/strcpy.S
+ * Contributed by Richard Henderson (rth@tamu.edu)
+ *
+ * Copy a null-terminated string from SRC to DST.  Return a pointer
+ * to the null-terminator in the source.
+ */
+#include <linux/export.h>
+	.text
+
+	.align 3
+	.globl strcpy
+	.ent strcpy
+strcpy:
+	.frame $30, 0, $26
+	.prologue 0
+
+	mov	$16, $0		# set up return value
+	mov	$26, $23	# set up return address
+	unop
+	br	__stxcpy	# do the copy
+
+	.end strcpy
+	EXPORT_SYMBOL(strcpy)