diff --git a/arch/arm64/include/asm/compat.h b/arch/arm64/include/asm/compat.h
index 9f362274a4f7..74575c3d6987 100644
--- a/arch/arm64/include/asm/compat.h
+++ b/arch/arm64/include/asm/compat.h
@@ -83,10 +83,6 @@ struct compat_statfs {
 	int		f_spare[4];
 };
 
-#define COMPAT_RLIM_INFINITY		0xffffffff
-
-#define COMPAT_OFF_T_MAX	0x7fffffff
-
 #define compat_user_stack_pointer() (user_stack_pointer(task_pt_regs(current)))
 #define COMPAT_MINSIGSTKSZ	2048
 
diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h
index 7b7e05c02691..13d437bcbf58 100644
--- a/arch/arm64/include/asm/debug-monitors.h
+++ b/arch/arm64/include/asm/debug-monitors.h
@@ -104,6 +104,7 @@ void user_regs_reset_single_step(struct user_pt_regs *regs,
 void kernel_enable_single_step(struct pt_regs *regs);
 void kernel_disable_single_step(void);
 int kernel_active_single_step(void);
+void kernel_rewind_single_step(struct pt_regs *regs);
 
 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 int reinstall_suspended_bps(struct pt_regs *regs);
diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c
index 8a9052cf3013..1febd412b4d2 100644
--- a/arch/arm64/kernel/armv8_deprecated.c
+++ b/arch/arm64/kernel/armv8_deprecated.c
@@ -420,14 +420,14 @@ static DEFINE_MUTEX(insn_emulation_mutex);
 
 static void enable_insn_hw_mode(void *data)
 {
-	struct insn_emulation *insn = (struct insn_emulation *)data;
+	struct insn_emulation *insn = data;
 	if (insn->set_hw_mode)
 		insn->set_hw_mode(true);
 }
 
 static void disable_insn_hw_mode(void *data)
 {
-	struct insn_emulation *insn = (struct insn_emulation *)data;
+	struct insn_emulation *insn = data;
 	if (insn->set_hw_mode)
 		insn->set_hw_mode(false);
 }
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 3da09778267e..64f2ecbdfe5c 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -438,6 +438,11 @@ int kernel_active_single_step(void)
 }
 NOKPROBE_SYMBOL(kernel_active_single_step);
 
+void kernel_rewind_single_step(struct pt_regs *regs)
+{
+	set_regs_spsr_ss(regs);
+}
+
 /* ptrace API */
 void user_enable_single_step(struct task_struct *task)
 {
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 9e7e50a0fd76..2fbafa5cc7ac 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -299,7 +299,7 @@ void task_set_vl_onexec(struct task_struct *task, enum vec_type type,
 /*
  * TIF_SME controls whether a task can use SME without trapping while
  * in userspace, when TIF_SME is set then we must have storage
- * alocated in sve_state and sme_state to store the contents of both ZA
+ * allocated in sve_state and sme_state to store the contents of both ZA
  * and the SVE registers for both streaming and non-streaming modes.
  *
  * If both SVCR.ZA and SVCR.SM are disabled then at any point we
@@ -1477,7 +1477,7 @@ void do_sve_acc(unsigned long esr, struct pt_regs *regs)
  *
  * TIF_SME should be clear on entry: otherwise, fpsimd_restore_current_state()
  * would have disabled the SME access trap for userspace during
- * ret_to_user, making an SVE access trap impossible in that case.
+ * ret_to_user, making an SME access trap impossible in that case.
  */
 void do_sme_acc(unsigned long esr, struct pt_regs *regs)
 {
diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c
index d833d78a7f31..964ba6efc7a0 100644
--- a/arch/arm64/kernel/idreg-override.c
+++ b/arch/arm64/kernel/idreg-override.c
@@ -178,6 +178,13 @@ static const struct {
 	{ "nokaslr",			"kaslr.disabled=1" },
 };
 
+static int __init parse_nokaslr(char *unused)
+{
+	/* nokaslr param handling is done by early cpufeature code */
+	return 0;
+}
+early_param("nokaslr", parse_nokaslr);
+
 static int __init find_field(const char *cmdline,
 			     const struct ftr_set_desc *reg, int f, u64 *v)
 {
diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
index cda9c1e9864f..4e1f983df3d1 100644
--- a/arch/arm64/kernel/kgdb.c
+++ b/arch/arm64/kernel/kgdb.c
@@ -224,6 +224,8 @@ int kgdb_arch_handle_exception(int exception_vector, int signo,
 		 */
 		if (!kernel_active_single_step())
 			kernel_enable_single_step(linux_regs);
+		else
+			kernel_rewind_single_step(linux_regs);
 		err = 0;
 		break;
 	default:
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index 22da7fc1ff50..078910db77a4 100644
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/kexec.h>
 #include <linux/page-flags.h>
+#include <linux/reboot.h>
 #include <linux/set_memory.h>
 #include <linux/smp.h>
 
@@ -102,7 +103,7 @@ static void kexec_segment_flush(const struct kimage *kimage)
 /* Allocates pages for kexec page table */
 static void *kexec_page_alloc(void *arg)
 {
-	struct kimage *kimage = (struct kimage *)arg;
+	struct kimage *kimage = arg;
 	struct page *page = kimage_alloc_control_pages(kimage, 0);
 	void *vaddr = NULL;
 
diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
index fca9cc6f5581..05f40c4e18fd 100644
--- a/arch/arm64/kernel/proton-pack.c
+++ b/arch/arm64/kernel/proton-pack.c
@@ -966,9 +966,6 @@ static void this_cpu_set_vectors(enum arm64_bp_harden_el1_vectors slot)
 {
 	const char *v = arm64_get_bp_hardening_vector(slot);
 
-	if (slot < 0)
-		return;
-
 	__this_cpu_write(this_cpu_vector, v);
 
 	/*
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 06a02707f488..2cfc810d0a5b 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -651,7 +651,7 @@ static int parse_user_sigframe(struct user_ctxs *user,
 			break;
 
 		case TPIDR2_MAGIC:
-			if (!system_supports_sme())
+			if (!system_supports_tpidr2())
 				goto invalid;
 
 			if (user->tpidr2)
@@ -802,7 +802,7 @@ static int restore_sigframe(struct pt_regs *regs,
 			err = restore_fpsimd_context(&user);
 	}
 
-	if (err == 0 && system_supports_sme() && user.tpidr2)
+	if (err == 0 && system_supports_tpidr2() && user.tpidr2)
 		err = restore_tpidr2_context(&user);
 
 	if (err == 0 && system_supports_sme() && user.za)
@@ -893,6 +893,13 @@ static int setup_sigframe_layout(struct rt_sigframe_user_layout *user,
 			return err;
 	}
 
+	if (system_supports_tpidr2()) {
+		err = sigframe_alloc(user, &user->tpidr2_offset,
+				     sizeof(struct tpidr2_context));
+		if (err)
+			return err;
+	}
+
 	if (system_supports_sme()) {
 		unsigned int vl;
 		unsigned int vq = 0;
@@ -902,11 +909,6 @@ static int setup_sigframe_layout(struct rt_sigframe_user_layout *user,
 		else
 			vl = task_get_sme_vl(current);
 
-		err = sigframe_alloc(user, &user->tpidr2_offset,
-				     sizeof(struct tpidr2_context));
-		if (err)
-			return err;
-
 		if (thread_za_enabled(&current->thread))
 			vq = sve_vq_from_vl(vl);
 
@@ -974,7 +976,7 @@ static int setup_sigframe(struct rt_sigframe_user_layout *user,
 	}
 
 	/* TPIDR2 if supported */
-	if (system_supports_sme() && err == 0) {
+	if (system_supports_tpidr2() && err == 0) {
 		struct tpidr2_context __user *tpidr2_ctx =
 			apply_user_offset(user, user->tpidr2_offset);
 		err |= preserve_tpidr2_context(tpidr2_ctx);
diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c
index 1e1a51510e83..f9040bd61081 100644
--- a/drivers/firmware/arm_sdei.c
+++ b/drivers/firmware/arm_sdei.c
@@ -43,6 +43,8 @@ static asmlinkage void (*sdei_firmware_call)(unsigned long function_id,
 /* entry point from firmware to arch asm code */
 static unsigned long sdei_entry_point;
 
+static int sdei_hp_state;
+
 struct sdei_event {
 	/* These three are protected by the sdei_list_lock */
 	struct list_head	list;
@@ -301,8 +303,6 @@ int sdei_mask_local_cpu(void)
 {
 	int err;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_MASK, 0, 0, 0, 0, 0, NULL);
 	if (err && err != -EIO) {
 		pr_warn_once("failed to mask CPU[%u]: %d\n",
@@ -315,6 +315,7 @@ int sdei_mask_local_cpu(void)
 
 static void _ipi_mask_cpu(void *ignored)
 {
+	WARN_ON_ONCE(preemptible());
 	sdei_mask_local_cpu();
 }
 
@@ -322,8 +323,6 @@ int sdei_unmask_local_cpu(void)
 {
 	int err;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_UNMASK, 0, 0, 0, 0, 0, NULL);
 	if (err && err != -EIO) {
 		pr_warn_once("failed to unmask CPU[%u]: %d\n",
@@ -336,6 +335,7 @@ int sdei_unmask_local_cpu(void)
 
 static void _ipi_unmask_cpu(void *ignored)
 {
+	WARN_ON_ONCE(preemptible());
 	sdei_unmask_local_cpu();
 }
 
@@ -343,6 +343,8 @@ static void _ipi_private_reset(void *ignored)
 {
 	int err;
 
+	WARN_ON_ONCE(preemptible());
+
 	err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PRIVATE_RESET, 0, 0, 0, 0, 0,
 			     NULL);
 	if (err && err != -EIO)
@@ -389,8 +391,6 @@ static void _local_event_enable(void *data)
 	int err;
 	struct sdei_crosscall_args *arg = data;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = sdei_api_event_enable(arg->event->event_num);
 
 	sdei_cross_call_return(arg, err);
@@ -479,8 +479,6 @@ static void _local_event_unregister(void *data)
 	int err;
 	struct sdei_crosscall_args *arg = data;
 
-	WARN_ON_ONCE(preemptible());
-
 	err = sdei_api_event_unregister(arg->event->event_num);
 
 	sdei_cross_call_return(arg, err);
@@ -561,8 +559,6 @@ static void _local_event_register(void *data)
 	struct sdei_registered_event *reg;
 	struct sdei_crosscall_args *arg = data;
 
-	WARN_ON(preemptible());
-
 	reg = per_cpu_ptr(arg->event->private_registered, smp_processor_id());
 	err = sdei_api_event_register(arg->event->event_num, sdei_entry_point,
 				      reg, 0, 0);
@@ -717,6 +713,8 @@ static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action,
 {
 	int rv;
 
+	WARN_ON_ONCE(preemptible());
+
 	switch (action) {
 	case CPU_PM_ENTER:
 		rv = sdei_mask_local_cpu();
@@ -765,7 +763,7 @@ static int sdei_device_freeze(struct device *dev)
 	int err;
 
 	/* unregister private events */
-	cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
+	cpuhp_remove_state(sdei_entry_point);
 
 	err = sdei_unregister_shared();
 	if (err)
@@ -786,12 +784,15 @@ static int sdei_device_thaw(struct device *dev)
 		return err;
 	}
 
-	err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
+	err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SDEI",
 				&sdei_cpuhp_up, &sdei_cpuhp_down);
-	if (err)
+	if (err < 0) {
 		pr_warn("Failed to re-register CPU hotplug notifier...\n");
+		return err;
+	}
 
-	return err;
+	sdei_hp_state = err;
+	return 0;
 }
 
 static int sdei_device_restore(struct device *dev)
@@ -823,7 +824,7 @@ static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action,
 	 * We are going to reset the interface, after this there is no point
 	 * doing work when we take CPUs offline.
 	 */
-	cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
+	cpuhp_remove_state(sdei_hp_state);
 
 	sdei_platform_reset();
 
@@ -1003,13 +1004,15 @@ static int sdei_probe(struct platform_device *pdev)
 		goto remove_cpupm;
 	}
 
-	err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
+	err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SDEI",
 				&sdei_cpuhp_up, &sdei_cpuhp_down);
-	if (err) {
+	if (err < 0) {
 		pr_warn("Failed to register CPU hotplug notifier...\n");
 		goto remove_reboot;
 	}
 
+	sdei_hp_state = err;
+
 	return 0;
 
 remove_reboot:
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index c6fab004104a..5066fa20e3e9 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -163,7 +163,6 @@ enum cpuhp_state {
 	CPUHP_AP_PERF_X86_CSTATE_STARTING,
 	CPUHP_AP_PERF_XTENSA_STARTING,
 	CPUHP_AP_MIPS_OP_LOONGSON3_STARTING,
-	CPUHP_AP_ARM_SDEI_STARTING,
 	CPUHP_AP_ARM_VFP_STARTING,
 	CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING,
 	CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING,