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, 72 insertions, 0 deletions

diff --git a/tools/crypto/ccp/dbc.c b/tools/crypto/ccp/dbc.c
new file mode 100644
index 000000000..80248d3d3
--- /dev/null
+++ b/tools/crypto/ccp/dbc.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Secure Processor Dynamic Boost Control sample library
+ *
+ * Copyright (C) 2023 Advanced Micro Devices, Inc.
+ *
+ * Author: Mario Limonciello <mario.limonciello@amd.com>
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+/* if uapi header isn't installed, this might not yet exist */
+#ifndef __packed
+#define __packed __attribute__((packed))
+#endif
+#include <linux/psp-dbc.h>
+
+int get_nonce(int fd, void *nonce_out, void *signature)
+{
+	struct dbc_user_nonce tmp = {
+		.auth_needed = !!signature,
+	};
+
+	assert(nonce_out);
+
+	if (signature)
+		memcpy(tmp.signature, signature, sizeof(tmp.signature));
+
+	if (ioctl(fd, DBCIOCNONCE, &tmp))
+		return errno;
+	memcpy(nonce_out, tmp.nonce, sizeof(tmp.nonce));
+
+	return 0;
+}
+
+int set_uid(int fd, __u8 *uid, __u8 *signature)
+{
+	struct dbc_user_setuid tmp;
+
+	assert(uid);
+	assert(signature);
+
+	memcpy(tmp.uid, uid, sizeof(tmp.uid));
+	memcpy(tmp.signature, signature, sizeof(tmp.signature));
+
+	if (ioctl(fd, DBCIOCUID, &tmp))
+		return errno;
+	return 0;
+}
+
+int process_param(int fd, int msg_index, __u8 *signature, int *data)
+{
+	struct dbc_user_param tmp = {
+		.msg_index = msg_index,
+		.param = *data,
+	};
+
+	assert(signature);
+	assert(data);
+
+	memcpy(tmp.signature, signature, sizeof(tmp.signature));
+
+	if (ioctl(fd, DBCIOCPARAM, &tmp))
+		return errno;
+
+	*data = tmp.param;
+	memcpy(signature, tmp.signature, sizeof(tmp.signature));
+	return 0;
+}