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, 42 insertions, 0 deletions

diff --git a/init/do_mounts.h b/init/do_mounts.h
new file mode 100644
index 000000000..a386ee531
--- /dev/null
+++ b/init/do_mounts.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/kernel.h>
+#include <linux/blkdev.h>
+#include <linux/init.h>
+#include <linux/syscalls.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/mount.h>
+#include <linux/major.h>
+#include <linux/root_dev.h>
+#include <linux/init_syscalls.h>
+#include <linux/task_work.h>
+#include <linux/file.h>
+
+void  mount_root_generic(char *name, char *pretty_name, int flags);
+void  mount_root(char *root_device_name);
+extern int root_mountflags;
+
+static inline __init int create_dev(char *name, dev_t dev)
+{
+	init_unlink(name);
+	return init_mknod(name, S_IFBLK | 0600, new_encode_dev(dev));
+}
+
+#ifdef CONFIG_BLK_DEV_RAM
+int __init rd_load_image(void);
+#else
+static inline int rd_load_image(void) { return 0; }
+#endif
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void __init initrd_load(void);
+#else
+static inline void initrd_load(void) { }
+#endif
+
+/* Ensure that async file closing finished to prevent spurious errors. */
+static inline void init_flush_fput(void)
+{
+	flush_delayed_fput();
+	task_work_run();
+}