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, 207 insertions, 0 deletions

diff --git a/security/tomoyo/memory.c b/security/tomoyo/memory.c
new file mode 100644
index 000000000..1b570bde7
--- /dev/null
+++ b/security/tomoyo/memory.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * security/tomoyo/memory.c
+ *
+ * Copyright (C) 2005-2011  NTT DATA CORPORATION
+ */
+
+#include <linux/hash.h>
+#include <linux/slab.h>
+#include "common.h"
+
+/**
+ * tomoyo_warn_oom - Print out of memory warning message.
+ *
+ * @function: Function's name.
+ */
+void tomoyo_warn_oom(const char *function)
+{
+	/* Reduce error messages. */
+	static pid_t tomoyo_last_pid;
+	const pid_t pid = current->pid;
+
+	if (tomoyo_last_pid != pid) {
+		pr_warn("ERROR: Out of memory at %s.\n", function);
+		tomoyo_last_pid = pid;
+	}
+	if (!tomoyo_policy_loaded)
+		panic("MAC Initialization failed.\n");
+}
+
+/* Memoy currently used by policy/audit log/query. */
+unsigned int tomoyo_memory_used[TOMOYO_MAX_MEMORY_STAT];
+/* Memory quota for "policy"/"audit log"/"query". */
+unsigned int tomoyo_memory_quota[TOMOYO_MAX_MEMORY_STAT];
+
+/**
+ * tomoyo_memory_ok - Check memory quota.
+ *
+ * @ptr: Pointer to allocated memory.
+ *
+ * Returns true on success, false otherwise.
+ *
+ * Returns true if @ptr is not NULL and quota not exceeded, false otherwise.
+ *
+ * Caller holds tomoyo_policy_lock mutex.
+ */
+bool tomoyo_memory_ok(void *ptr)
+{
+	if (ptr) {
+		const size_t s = ksize(ptr);
+
+		tomoyo_memory_used[TOMOYO_MEMORY_POLICY] += s;
+		if (!tomoyo_memory_quota[TOMOYO_MEMORY_POLICY] ||
+		    tomoyo_memory_used[TOMOYO_MEMORY_POLICY] <=
+		    tomoyo_memory_quota[TOMOYO_MEMORY_POLICY])
+			return true;
+		tomoyo_memory_used[TOMOYO_MEMORY_POLICY] -= s;
+	}
+	tomoyo_warn_oom(__func__);
+	return false;
+}
+
+/**
+ * tomoyo_commit_ok - Check memory quota.
+ *
+ * @data:   Data to copy from.
+ * @size:   Size in byte.
+ *
+ * Returns pointer to allocated memory on success, NULL otherwise.
+ * @data is zero-cleared on success.
+ *
+ * Caller holds tomoyo_policy_lock mutex.
+ */
+void *tomoyo_commit_ok(void *data, const unsigned int size)
+{
+	void *ptr = kzalloc(size, GFP_NOFS | __GFP_NOWARN);
+
+	if (tomoyo_memory_ok(ptr)) {
+		memmove(ptr, data, size);
+		memset(data, 0, size);
+		return ptr;
+	}
+	kfree(ptr);
+	return NULL;
+}
+
+/**
+ * tomoyo_get_group - Allocate memory for "struct tomoyo_path_group"/"struct tomoyo_number_group".
+ *
+ * @param: Pointer to "struct tomoyo_acl_param".
+ * @idx:   Index number.
+ *
+ * Returns pointer to "struct tomoyo_group" on success, NULL otherwise.
+ */
+struct tomoyo_group *tomoyo_get_group(struct tomoyo_acl_param *param,
+				      const u8 idx)
+{
+	struct tomoyo_group e = { };
+	struct tomoyo_group *group = NULL;
+	struct list_head *list;
+	const char *group_name = tomoyo_read_token(param);
+	bool found = false;
+
+	if (!tomoyo_correct_word(group_name) || idx >= TOMOYO_MAX_GROUP)
+		return NULL;
+	e.group_name = tomoyo_get_name(group_name);
+	if (!e.group_name)
+		return NULL;
+	if (mutex_lock_interruptible(&tomoyo_policy_lock))
+		goto out;
+	list = &param->ns->group_list[idx];
+	list_for_each_entry(group, list, head.list) {
+		if (e.group_name != group->group_name ||
+		    atomic_read(&group->head.users) == TOMOYO_GC_IN_PROGRESS)
+			continue;
+		atomic_inc(&group->head.users);
+		found = true;
+		break;
+	}
+	if (!found) {
+		struct tomoyo_group *entry = tomoyo_commit_ok(&e, sizeof(e));
+
+		if (entry) {
+			INIT_LIST_HEAD(&entry->member_list);
+			atomic_set(&entry->head.users, 1);
+			list_add_tail_rcu(&entry->head.list, list);
+			group = entry;
+			found = true;
+		}
+	}
+	mutex_unlock(&tomoyo_policy_lock);
+out:
+	tomoyo_put_name(e.group_name);
+	return found ? group : NULL;
+}
+
+/*
+ * tomoyo_name_list is used for holding string data used by TOMOYO.
+ * Since same string data is likely used for multiple times (e.g.
+ * "/lib/libc-2.5.so"), TOMOYO shares string data in the form of
+ * "const struct tomoyo_path_info *".
+ */
+struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
+
+/**
+ * tomoyo_get_name - Allocate permanent memory for string data.
+ *
+ * @name: The string to store into the permernent memory.
+ *
+ * Returns pointer to "struct tomoyo_path_info" on success, NULL otherwise.
+ */
+const struct tomoyo_path_info *tomoyo_get_name(const char *name)
+{
+	struct tomoyo_name *ptr;
+	unsigned int hash;
+	int len;
+	struct list_head *head;
+
+	if (!name)
+		return NULL;
+	len = strlen(name) + 1;
+	hash = full_name_hash(NULL, (const unsigned char *) name, len - 1);
+	head = &tomoyo_name_list[hash_long(hash, TOMOYO_HASH_BITS)];
+	if (mutex_lock_interruptible(&tomoyo_policy_lock))
+		return NULL;
+	list_for_each_entry(ptr, head, head.list) {
+		if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name) ||
+		    atomic_read(&ptr->head.users) == TOMOYO_GC_IN_PROGRESS)
+			continue;
+		atomic_inc(&ptr->head.users);
+		goto out;
+	}
+	ptr = kzalloc(sizeof(*ptr) + len, GFP_NOFS | __GFP_NOWARN);
+	if (tomoyo_memory_ok(ptr)) {
+		ptr->entry.name = ((char *) ptr) + sizeof(*ptr);
+		memmove((char *) ptr->entry.name, name, len);
+		atomic_set(&ptr->head.users, 1);
+		tomoyo_fill_path_info(&ptr->entry);
+		list_add_tail(&ptr->head.list, head);
+	} else {
+		kfree(ptr);
+		ptr = NULL;
+	}
+out:
+	mutex_unlock(&tomoyo_policy_lock);
+	return ptr ? &ptr->entry : NULL;
+}
+
+/* Initial namespace.*/
+struct tomoyo_policy_namespace tomoyo_kernel_namespace;
+
+/**
+ * tomoyo_mm_init - Initialize mm related code.
+ */
+void __init tomoyo_mm_init(void)
+{
+	int idx;
+
+	for (idx = 0; idx < TOMOYO_MAX_HASH; idx++)
+		INIT_LIST_HEAD(&tomoyo_name_list[idx]);
+	tomoyo_kernel_namespace.name = "<kernel>";
+	tomoyo_init_policy_namespace(&tomoyo_kernel_namespace);
+	tomoyo_kernel_domain.ns = &tomoyo_kernel_namespace;
+	INIT_LIST_HEAD(&tomoyo_kernel_domain.acl_info_list);
+	tomoyo_kernel_domain.domainname = tomoyo_get_name("<kernel>");
+	list_add_tail_rcu(&tomoyo_kernel_domain.list, &tomoyo_domain_list);
+}