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, 65 insertions, 0 deletions

diff --git a/fs/fuse/sysctl.c b/fs/fuse/sysctl.c
new file mode 100644
index 000000000..74eca5ce9
--- /dev/null
+++ b/fs/fuse/sysctl.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/fuse/fuse_sysctl.c
+ *
+ * Sysctl interface to fuse parameters
+ */
+#include <linux/sysctl.h>
+
+#include "sysctl.h"
+#include "fuse_i.h"
+
+static struct ctl_table_header *fuse_table_header;
+
+/* Bound by fuse_init_out max_pages, which is a u16 */
+static unsigned int sysctl_fuse_max_pages_limit = 65535;
+
+/*
+ * fuse_init_out request timeouts are u16.
+ * This goes up to ~18 hours, which is plenty for a timeout.
+ */
+static unsigned int sysctl_fuse_req_timeout_limit = 65535;
+
+static const struct ctl_table fuse_sysctl_table[] = {
+	{
+		.procname	= "max_pages_limit",
+		.data		= &fuse_max_pages_limit,
+		.maxlen		= sizeof(fuse_max_pages_limit),
+		.mode		= 0644,
+		.proc_handler	= proc_douintvec_minmax,
+		.extra1		= SYSCTL_ONE,
+		.extra2		= &sysctl_fuse_max_pages_limit,
+	},
+	{
+		.procname	= "default_request_timeout",
+		.data		= &fuse_default_req_timeout,
+		.maxlen		= sizeof(fuse_default_req_timeout),
+		.mode		= 0644,
+		.proc_handler	= proc_douintvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= &sysctl_fuse_req_timeout_limit,
+	},
+	{
+		.procname	= "max_request_timeout",
+		.data		= &fuse_max_req_timeout,
+		.maxlen		= sizeof(fuse_max_req_timeout),
+		.mode		= 0644,
+		.proc_handler	= proc_douintvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= &sysctl_fuse_req_timeout_limit,
+	},
+};
+
+int fuse_sysctl_register(void)
+{
+	fuse_table_header = register_sysctl("fs/fuse", fuse_sysctl_table);
+	if (!fuse_table_header)
+		return -ENOMEM;
+	return 0;
+}
+
+void fuse_sysctl_unregister(void)
+{
+	unregister_sysctl_table(fuse_table_header);
+	fuse_table_header = NULL;
+}