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, 139 insertions, 0 deletions

diff --git a/arch/powerpc/boot/ps3.c b/arch/powerpc/boot/ps3.c
new file mode 100644
index 000000000..89ff46b8b
--- /dev/null
+++ b/arch/powerpc/boot/ps3.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  PS3 bootwrapper support.
+ *
+ *  Copyright (C) 2007 Sony Computer Entertainment Inc.
+ *  Copyright 2007 Sony Corp.
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+#include "types.h"
+#include "elf.h"
+#include "string.h"
+#include "stdio.h"
+#include "page.h"
+#include "ops.h"
+
+extern int lv1_panic(u64 in_1);
+extern int lv1_get_logical_partition_id(u64 *out_1);
+extern int lv1_get_logical_ppe_id(u64 *out_1);
+extern int lv1_get_repository_node_value(u64 in_1, u64 in_2, u64 in_3,
+	u64 in_4, u64 in_5, u64 *out_1, u64 *out_2);
+
+BSS_STACK(4096);
+
+/* A buffer that may be edited by tools operating on a zImage binary so as to
+ * edit the command line passed to vmlinux (by setting /chosen/bootargs).
+ * The buffer is put in its own section so that tools may locate it easier.
+ */
+
+static char cmdline[BOOT_COMMAND_LINE_SIZE]
+	__attribute__((__section__("__builtin_cmdline")));
+
+static void prep_cmdline(void *chosen)
+{
+	if (cmdline[0] == '\0')
+		getprop(chosen, "bootargs", cmdline, BOOT_COMMAND_LINE_SIZE-1);
+	else
+		setprop_str(chosen, "bootargs", cmdline);
+
+	printf("cmdline: '%s'\n", cmdline);
+}
+
+static void ps3_console_write(const char *buf, int len)
+{
+}
+
+static void ps3_exit(void)
+{
+	printf("ps3_exit\n");
+
+	/* lv1_panic will shutdown the lpar. */
+
+	lv1_panic(0); /* zero = do not reboot */
+	while (1);
+}
+
+static int ps3_repository_read_rm_size(u64 *rm_size)
+{
+	int result;
+	u64 lpar_id;
+	u64 ppe_id;
+	u64 v2;
+
+	result = lv1_get_logical_partition_id(&lpar_id);
+
+	if (result)
+		return -1;
+
+	result = lv1_get_logical_ppe_id(&ppe_id);
+
+	if (result)
+		return -1;
+
+	/*
+	 * n1: 0000000062690000 : ....bi..
+	 * n2: 7075000000000000 : pu......
+	 * n3: 0000000000000001 : ........
+	 * n4: 726d5f73697a6500 : rm_size.
+	*/
+
+	result = lv1_get_repository_node_value(lpar_id, 0x0000000062690000ULL,
+		0x7075000000000000ULL, ppe_id, 0x726d5f73697a6500ULL, rm_size,
+		&v2);
+
+	printf("%s:%d: ppe_id  %lu \n", __func__, __LINE__,
+		(unsigned long)ppe_id);
+	printf("%s:%d: lpar_id %lu \n", __func__, __LINE__,
+		(unsigned long)lpar_id);
+	printf("%s:%d: rm_size %llxh \n", __func__, __LINE__, *rm_size);
+
+	return result ? -1 : 0;
+}
+
+void ps3_copy_vectors(void)
+{
+	extern char __system_reset_kernel[];
+
+	memcpy((void *)0x100, __system_reset_kernel, 512);
+	flush_cache((void *)0x100, 512);
+}
+
+void platform_init(void)
+{
+	const u32 heapsize = 0x1000000 - (u32)_end; /* 16MiB */
+	void *chosen;
+	unsigned long ft_addr;
+	u64 rm_size;
+
+	console_ops.write = ps3_console_write;
+	platform_ops.exit = ps3_exit;
+
+	printf("\n-- PS3 bootwrapper --\n");
+
+	simple_alloc_init(_end, heapsize, 32, 64);
+	fdt_init(_dtb_start);
+
+	chosen = finddevice("/chosen");
+
+	ps3_repository_read_rm_size(&rm_size);
+	dt_fixup_memory(0, rm_size);
+
+	if (&_initrd_end > &_initrd_start) {
+		setprop_val(chosen, "linux,initrd-start", (u32)(_initrd_start));
+		setprop_val(chosen, "linux,initrd-end", (u32)(_initrd_end));
+	}
+
+	prep_cmdline(chosen);
+
+	ft_addr = dt_ops.finalize();
+
+	ps3_copy_vectors();
+
+	printf(" flat tree at 0x%lx\n\r", ft_addr);
+
+	((kernel_entry_t)0)(ft_addr, 0, NULL);
+
+	ps3_exit();
+}