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, 55 insertions, 0 deletions

diff --git a/tools/testing/memblock/Makefile b/tools/testing/memblock/Makefile
new file mode 100644
index 000000000..d80982ccd
--- /dev/null
+++ b/tools/testing/memblock/Makefile
@@ -0,0 +1,55 @@
+# SPDX-License-Identifier: GPL-2.0
+
+# Memblock simulator requires AddressSanitizer (libasan) and liburcu development
+# packages installed
+CFLAGS += -I. -I../../include -Wall -O2 -fsanitize=address \
+	  -fsanitize=undefined -D CONFIG_PHYS_ADDR_T_64BIT
+LDFLAGS += -fsanitize=address -fsanitize=undefined
+TARGETS = main
+TEST_OFILES = tests/alloc_nid_api.o tests/alloc_helpers_api.o tests/alloc_api.o \
+		  tests/basic_api.o tests/common.o tests/alloc_exact_nid_api.o
+DEP_OFILES = memblock.o lib/slab.o mmzone.o slab.o cmdline.o
+OFILES = main.o $(DEP_OFILES) $(TEST_OFILES)
+EXTR_SRC = ../../../mm/memblock.c
+
+ifeq ($(BUILD), 32)
+	CFLAGS += -m32
+	LDFLAGS += -m32
+endif
+
+# Process user parameters
+include scripts/Makefile.include
+
+main: $(OFILES)
+
+$(OFILES): include
+
+include: ../../../include/linux/memblock.h ../../include/linux/*.h \
+	../../include/asm/*.h
+
+	@mkdir -p linux
+	test -L linux/memblock.h || ln -s ../../../../include/linux/memblock.h linux/memblock.h
+	test -L asm/asm.h || ln -s ../../../arch/x86/include/asm/asm.h asm/asm.h
+	test -L asm/cmpxchg.h || ln -s ../../../arch/x86/include/asm/cmpxchg.h asm/cmpxchg.h
+
+memblock.c: $(EXTR_SRC)
+	test -L memblock.c || ln -s $(EXTR_SRC) memblock.c
+
+clean:
+	$(RM) $(TARGETS) $(OFILES) linux/memblock.h memblock.c asm/asm.h asm/cmpxchg.h
+
+help:
+	@echo  'Memblock simulator'
+	@echo  ''
+	@echo  'Available targets:'
+	@echo  '  main		  - Build the memblock simulator'
+	@echo  '  clean		  - Remove generated files and symlinks in the directory'
+	@echo  ''
+	@echo  'Configuration:'
+	@echo  '  make MEMBLOCK_DEBUG=1     - enable memblock_dbg() messages'
+	@echo  '  make NUMA=1               - simulate enabled NUMA'
+	@echo  '  make 32BIT_PHYS_ADDR_T=1  - Use 32 bit physical addresses'
+
+vpath %.c ../../lib
+
+.PHONY: clean include help