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, 135 insertions, 0 deletions

diff --git a/drivers/reset/reset-hsdk.c b/drivers/reset/reset-hsdk.c
new file mode 100644
index 000000000..98460e087
--- /dev/null
+++ b/drivers/reset/reset-hsdk.c
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2017 Synopsys.
+ *
+ * Synopsys HSDK Development platform reset driver.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define to_hsdk_rst(p)	container_of((p), struct hsdk_rst, rcdev)
+
+struct hsdk_rst {
+	void __iomem			*regs_ctl;
+	void __iomem			*regs_rst;
+	spinlock_t			lock;
+	struct reset_controller_dev	rcdev;
+};
+
+static const u32 rst_map[] = {
+	BIT(16), /* APB_RST  */
+	BIT(17), /* AXI_RST  */
+	BIT(18), /* ETH_RST  */
+	BIT(19), /* USB_RST  */
+	BIT(20), /* SDIO_RST */
+	BIT(21), /* HDMI_RST */
+	BIT(22), /* GFX_RST  */
+	BIT(25), /* DMAC_RST */
+	BIT(31), /* EBI_RST  */
+};
+
+#define HSDK_MAX_RESETS			ARRAY_SIZE(rst_map)
+
+#define CGU_SYS_RST_CTRL		0x0
+#define CGU_IP_SW_RESET			0x0
+#define CGU_IP_SW_RESET_DELAY_SHIFT	16
+#define CGU_IP_SW_RESET_DELAY_MASK	GENMASK(31, CGU_IP_SW_RESET_DELAY_SHIFT)
+#define CGU_IP_SW_RESET_DELAY		0
+#define CGU_IP_SW_RESET_RESET		BIT(0)
+#define SW_RESET_TIMEOUT		10000
+
+static void hsdk_reset_config(struct hsdk_rst *rst, unsigned long id)
+{
+	writel(rst_map[id], rst->regs_ctl + CGU_SYS_RST_CTRL);
+}
+
+static int hsdk_reset_do(struct hsdk_rst *rst)
+{
+	u32 reg;
+
+	reg = readl(rst->regs_rst + CGU_IP_SW_RESET);
+	reg &= ~CGU_IP_SW_RESET_DELAY_MASK;
+	reg |= CGU_IP_SW_RESET_DELAY << CGU_IP_SW_RESET_DELAY_SHIFT;
+	reg |= CGU_IP_SW_RESET_RESET;
+	writel(reg, rst->regs_rst + CGU_IP_SW_RESET);
+
+	/* wait till reset bit is back to 0 */
+	return readl_poll_timeout_atomic(rst->regs_rst + CGU_IP_SW_RESET, reg,
+		!(reg & CGU_IP_SW_RESET_RESET), 5, SW_RESET_TIMEOUT);
+}
+
+static int hsdk_reset_reset(struct reset_controller_dev *rcdev,
+			      unsigned long id)
+{
+	struct hsdk_rst *rst = to_hsdk_rst(rcdev);
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&rst->lock, flags);
+	hsdk_reset_config(rst, id);
+	ret = hsdk_reset_do(rst);
+	spin_unlock_irqrestore(&rst->lock, flags);
+
+	return ret;
+}
+
+static const struct reset_control_ops hsdk_reset_ops = {
+	.reset	= hsdk_reset_reset,
+	.deassert = hsdk_reset_reset,
+};
+
+static int hsdk_reset_probe(struct platform_device *pdev)
+{
+	struct hsdk_rst *rst;
+
+	rst = devm_kzalloc(&pdev->dev, sizeof(*rst), GFP_KERNEL);
+	if (!rst)
+		return -ENOMEM;
+
+	rst->regs_ctl = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(rst->regs_ctl))
+		return PTR_ERR(rst->regs_ctl);
+
+	rst->regs_rst = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(rst->regs_rst))
+		return PTR_ERR(rst->regs_rst);
+
+	spin_lock_init(&rst->lock);
+
+	rst->rcdev.owner = THIS_MODULE;
+	rst->rcdev.ops = &hsdk_reset_ops;
+	rst->rcdev.of_node = pdev->dev.of_node;
+	rst->rcdev.nr_resets = HSDK_MAX_RESETS;
+	rst->rcdev.of_reset_n_cells = 1;
+
+	return reset_controller_register(&rst->rcdev);
+}
+
+static const struct of_device_id hsdk_reset_dt_match[] = {
+	{ .compatible = "snps,hsdk-reset" },
+	{ },
+};
+
+static struct platform_driver hsdk_reset_driver = {
+	.probe	= hsdk_reset_probe,
+	.driver	= {
+		.name = "hsdk-reset",
+		.of_match_table = hsdk_reset_dt_match,
+	},
+};
+builtin_platform_driver(hsdk_reset_driver);
+
+MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");
+MODULE_DESCRIPTION("Synopsys HSDK SDP reset driver");
+MODULE_LICENSE("GPL v2");