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, 357 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/utalloc.c b/drivers/acpi/acpica/utalloc.c
new file mode 100644
index 000000000..da12b6fec
--- /dev/null
+++ b/drivers/acpi/acpica/utalloc.c
@@ -0,0 +1,357 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: utalloc - local memory allocation routines
+ *
+ * Copyright (C) 2000 - 2026, Intel Corp.
+ *
+ *****************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acdebug.h"
+
+#define _COMPONENT          ACPI_UTILITIES
+ACPI_MODULE_NAME("utalloc")
+
+#if !defined (USE_NATIVE_ALLOCATE_ZEROED)
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_os_allocate_zeroed
+ *
+ * PARAMETERS:  size                - Size of the allocation
+ *
+ * RETURN:      Address of the allocated memory on success, NULL on failure.
+ *
+ * DESCRIPTION: Subsystem equivalent of calloc. Allocate and zero memory.
+ *              This is the default implementation. Can be overridden via the
+ *              USE_NATIVE_ALLOCATE_ZEROED flag.
+ *
+ ******************************************************************************/
+void *acpi_os_allocate_zeroed(acpi_size size)
+{
+	void *allocation;
+
+	ACPI_FUNCTION_ENTRY();
+
+	allocation = acpi_os_allocate(size);
+	if (allocation) {
+
+		/* Clear the memory block */
+
+		memset(allocation, 0, size);
+	}
+
+	return (allocation);
+}
+
+#endif				/* !USE_NATIVE_ALLOCATE_ZEROED */
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_create_caches
+ *
+ * PARAMETERS:  None
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Create all local caches
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ut_create_caches(void)
+{
+	acpi_status status;
+
+	/* Object Caches, for frequently used objects */
+
+	status =
+	    acpi_os_create_cache("Acpi-Namespace",
+				 sizeof(struct acpi_namespace_node),
+				 ACPI_MAX_NAMESPACE_CACHE_DEPTH,
+				 &acpi_gbl_namespace_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	status =
+	    acpi_os_create_cache("Acpi-State", sizeof(union acpi_generic_state),
+				 ACPI_MAX_STATE_CACHE_DEPTH,
+				 &acpi_gbl_state_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	status =
+	    acpi_os_create_cache("Acpi-Parse",
+				 sizeof(struct acpi_parse_obj_common),
+				 ACPI_MAX_PARSE_CACHE_DEPTH,
+				 &acpi_gbl_ps_node_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	status =
+	    acpi_os_create_cache("Acpi-ParseExt",
+				 sizeof(struct acpi_parse_obj_named),
+				 ACPI_MAX_EXTPARSE_CACHE_DEPTH,
+				 &acpi_gbl_ps_node_ext_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	status =
+	    acpi_os_create_cache("Acpi-Operand",
+				 sizeof(union acpi_operand_object),
+				 ACPI_MAX_OBJECT_CACHE_DEPTH,
+				 &acpi_gbl_operand_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+#ifdef ACPI_ASL_COMPILER
+	/*
+	 * For use with the ASL-/ASL+ option. This cache keeps track of regular
+	 * 0xA9 0x01 comments.
+	 */
+	status =
+	    acpi_os_create_cache("Acpi-Comment",
+				 sizeof(struct acpi_comment_node),
+				 ACPI_MAX_COMMENT_CACHE_DEPTH,
+				 &acpi_gbl_reg_comment_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	/*
+	 * This cache keeps track of the starting addresses of where the comments
+	 * lie. This helps prevent duplication of comments.
+	 */
+	status =
+	    acpi_os_create_cache("Acpi-Comment-Addr",
+				 sizeof(struct acpi_comment_addr_node),
+				 ACPI_MAX_COMMENT_CACHE_DEPTH,
+				 &acpi_gbl_comment_addr_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	/*
+	 * This cache will be used for nodes that represent files.
+	 */
+	status =
+	    acpi_os_create_cache("Acpi-File", sizeof(struct acpi_file_node),
+				 ACPI_MAX_COMMENT_CACHE_DEPTH,
+				 &acpi_gbl_file_cache);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+#endif
+
+#ifdef ACPI_DBG_TRACK_ALLOCATIONS
+
+	/* Memory allocation lists */
+
+	status = acpi_ut_create_list("Acpi-Global", 0, &acpi_gbl_global_list);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+
+	status =
+	    acpi_ut_create_list("Acpi-Namespace",
+				sizeof(struct acpi_namespace_node),
+				&acpi_gbl_ns_node_list);
+	if (ACPI_FAILURE(status)) {
+		return (status);
+	}
+#endif
+
+	return (AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_delete_caches
+ *
+ * PARAMETERS:  None
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Purge and delete all local caches
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ut_delete_caches(void)
+{
+#ifdef ACPI_DBG_TRACK_ALLOCATIONS
+	char buffer[7];
+
+	if (acpi_gbl_display_final_mem_stats) {
+		strcpy(buffer, "MEMORY");
+		(void)acpi_db_display_statistics(buffer);
+	}
+#endif
+
+	(void)acpi_os_delete_cache(acpi_gbl_namespace_cache);
+	acpi_gbl_namespace_cache = NULL;
+
+	(void)acpi_os_delete_cache(acpi_gbl_state_cache);
+	acpi_gbl_state_cache = NULL;
+
+	(void)acpi_os_delete_cache(acpi_gbl_operand_cache);
+	acpi_gbl_operand_cache = NULL;
+
+	(void)acpi_os_delete_cache(acpi_gbl_ps_node_cache);
+	acpi_gbl_ps_node_cache = NULL;
+
+	(void)acpi_os_delete_cache(acpi_gbl_ps_node_ext_cache);
+	acpi_gbl_ps_node_ext_cache = NULL;
+
+#ifdef ACPI_ASL_COMPILER
+	(void)acpi_os_delete_cache(acpi_gbl_reg_comment_cache);
+	acpi_gbl_reg_comment_cache = NULL;
+
+	(void)acpi_os_delete_cache(acpi_gbl_comment_addr_cache);
+	acpi_gbl_comment_addr_cache = NULL;
+
+	(void)acpi_os_delete_cache(acpi_gbl_file_cache);
+	acpi_gbl_file_cache = NULL;
+#endif
+
+#ifdef ACPI_DBG_TRACK_ALLOCATIONS
+
+	/* Debug only - display leftover memory allocation, if any */
+
+	acpi_ut_dump_allocations(ACPI_UINT32_MAX, NULL);
+
+	/* Free memory lists */
+
+	acpi_os_free(acpi_gbl_global_list);
+	acpi_gbl_global_list = NULL;
+
+	acpi_os_free(acpi_gbl_ns_node_list);
+	acpi_gbl_ns_node_list = NULL;
+#endif
+
+	return (AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_validate_buffer
+ *
+ * PARAMETERS:  buffer              - Buffer descriptor to be validated
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Perform parameter validation checks on an struct acpi_buffer
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ut_validate_buffer(struct acpi_buffer *buffer)
+{
+
+	/* Obviously, the structure pointer must be valid */
+
+	if (!buffer) {
+		return (AE_BAD_PARAMETER);
+	}
+
+	/* Special semantics for the length */
+
+	if ((buffer->length == ACPI_NO_BUFFER) ||
+	    (buffer->length == ACPI_ALLOCATE_BUFFER) ||
+	    (buffer->length == ACPI_ALLOCATE_LOCAL_BUFFER)) {
+		return (AE_OK);
+	}
+
+	/* Length is valid, the buffer pointer must be also */
+
+	if (!buffer->pointer) {
+		return (AE_BAD_PARAMETER);
+	}
+
+	return (AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_initialize_buffer
+ *
+ * PARAMETERS:  buffer              - Buffer to be validated
+ *              required_length     - Length needed
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Validate that the buffer is of the required length or
+ *              allocate a new buffer. Returned buffer is always zeroed.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ut_initialize_buffer(struct acpi_buffer *buffer, acpi_size required_length)
+{
+	acpi_size input_buffer_length;
+
+	/* Parameter validation */
+
+	if (!buffer || !required_length) {
+		return (AE_BAD_PARAMETER);
+	}
+
+	/*
+	 * Buffer->Length is used as both an input and output parameter. Get the
+	 * input actual length and set the output required buffer length.
+	 */
+	input_buffer_length = buffer->length;
+	buffer->length = required_length;
+
+	/*
+	 * The input buffer length contains the actual buffer length, or the type
+	 * of buffer to be allocated by this routine.
+	 */
+	switch (input_buffer_length) {
+	case ACPI_NO_BUFFER:
+
+		/* Return the exception (and the required buffer length) */
+
+		return (AE_BUFFER_OVERFLOW);
+
+	case ACPI_ALLOCATE_BUFFER:
+		/*
+		 * Allocate a new buffer. We directectly call acpi_os_allocate here to
+		 * purposefully bypass the (optionally enabled) internal allocation
+		 * tracking mechanism since we only want to track internal
+		 * allocations. Note: The caller should use acpi_os_free to free this
+		 * buffer created via ACPI_ALLOCATE_BUFFER.
+		 */
+		buffer->pointer = acpi_os_allocate(required_length);
+		break;
+
+	case ACPI_ALLOCATE_LOCAL_BUFFER:
+
+		/* Allocate a new buffer with local interface to allow tracking */
+
+		buffer->pointer = ACPI_ALLOCATE(required_length);
+		break;
+
+	default:
+
+		/* Existing buffer: Validate the size of the buffer */
+
+		if (input_buffer_length < required_length) {
+			return (AE_BUFFER_OVERFLOW);
+		}
+		break;
+	}
+
+	/* Validate allocation from above or input buffer pointer */
+
+	if (!buffer->pointer) {
+		return (AE_NO_MEMORY);
+	}
+
+	/* Have a valid buffer, clear it */
+
+	memset(buffer->pointer, 0, required_length);
+	return (AE_OK);
+}