28 files changed, 557 insertions, 221 deletions

diff --git a/kernel/bpf/bpf_inode_storage.c b/kernel/bpf/bpf_inode_storage.c
index da753721457c..2921ca39a93e 100644
--- a/kernel/bpf/bpf_inode_storage.c
+++ b/kernel/bpf/bpf_inode_storage.c
@@ -109,7 +109,7 @@ static void *bpf_fd_inode_storage_lookup_elem(struct bpf_map *map, void *key)
 	fd = *(int *)key;
 	f = fget_raw(fd);
 	if (!f)
-		return NULL;
+		return ERR_PTR(-EBADF);
 
 	sdata = inode_storage_lookup(f->f_inode, map, true);
 	fput(f);
diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index 1a666a975416..70f6fd4fa305 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -430,7 +430,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
 
 		tprogs[BPF_TRAMP_FENTRY].progs[0] = prog;
 		tprogs[BPF_TRAMP_FENTRY].nr_progs = 1;
-		err = arch_prepare_bpf_trampoline(image,
+		err = arch_prepare_bpf_trampoline(NULL, image,
 						  st_map->image + PAGE_SIZE,
 						  &st_ops->func_models[i], 0,
 						  tprogs, NULL);
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 3a283bf97f2f..75244ecb2389 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -827,7 +827,7 @@ static int __init bpf_jit_charge_init(void)
 }
 pure_initcall(bpf_jit_charge_init);
 
-static int bpf_jit_charge_modmem(u32 pages)
+int bpf_jit_charge_modmem(u32 pages)
 {
 	if (atomic_long_add_return(pages, &bpf_jit_current) >
 	    (bpf_jit_limit >> PAGE_SHIFT)) {
@@ -840,7 +840,7 @@ static int bpf_jit_charge_modmem(u32 pages)
 	return 0;
 }
 
-static void bpf_jit_uncharge_modmem(u32 pages)
+void bpf_jit_uncharge_modmem(u32 pages)
 {
 	atomic_long_sub(pages, &bpf_jit_current);
 }
diff --git a/kernel/bpf/preload/bpf_preload_kern.c b/kernel/bpf/preload/bpf_preload_kern.c
index 79c5772465f1..53736e52c1df 100644
--- a/kernel/bpf/preload/bpf_preload_kern.c
+++ b/kernel/bpf/preload/bpf_preload_kern.c
@@ -60,9 +60,12 @@ static int finish(void)
 			 &magic, sizeof(magic), &pos);
 	if (n != sizeof(magic))
 		return -EPIPE;
+
 	tgid = umd_ops.info.tgid;
-	wait_event(tgid->wait_pidfd, thread_group_exited(tgid));
-	umd_ops.info.tgid = NULL;
+	if (tgid) {
+		wait_event(tgid->wait_pidfd, thread_group_exited(tgid));
+		umd_cleanup_helper(&umd_ops.info);
+	}
 	return 0;
 }
 
@@ -80,10 +83,18 @@ static int __init load_umd(void)
 
 static void __exit fini_umd(void)
 {
+	struct pid *tgid;
+
 	bpf_preload_ops = NULL;
+
 	/* kill UMD in case it's still there due to earlier error */
-	kill_pid(umd_ops.info.tgid, SIGKILL, 1);
-	umd_ops.info.tgid = NULL;
+	tgid = umd_ops.info.tgid;
+	if (tgid) {
+		kill_pid(tgid, SIGKILL, 1);
+
+		wait_event(tgid->wait_pidfd, thread_group_exited(tgid));
+		umd_cleanup_helper(&umd_ops.info);
+	}
 	umd_unload_blob(&umd_ops.info);
 }
 late_initcall(load_umd);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index c859bc46d06c..250503482cda 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -854,6 +854,11 @@ static int map_create(union bpf_attr *attr)
 			err = PTR_ERR(btf);
 			goto free_map;
 		}
+		if (btf_is_kernel(btf)) {
+			btf_put(btf);
+			err = -EACCES;
+			goto free_map;
+		}
 		map->btf = btf;
 
 		if (attr->btf_value_type_id) {
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 7bc3b3209224..1f3a4be4b175 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -57,19 +57,10 @@ void bpf_image_ksym_del(struct bpf_ksym *ksym)
 			   PAGE_SIZE, true, ksym->name);
 }
 
-static void bpf_trampoline_ksym_add(struct bpf_trampoline *tr)
-{
-	struct bpf_ksym *ksym = &tr->ksym;
-
-	snprintf(ksym->name, KSYM_NAME_LEN, "bpf_trampoline_%llu", tr->key);
-	bpf_image_ksym_add(tr->image, ksym);
-}
-
 static struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
 {
 	struct bpf_trampoline *tr;
 	struct hlist_head *head;
-	void *image;
 	int i;
 
 	mutex_lock(&trampoline_mutex);
@@ -84,14 +75,6 @@ static struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
 	if (!tr)
 		goto out;
 
-	/* is_root was checked earlier. No need for bpf_jit_charge_modmem() */
-	image = bpf_jit_alloc_exec_page();
-	if (!image) {
-		kfree(tr);
-		tr = NULL;
-		goto out;
-	}
-
 	tr->key = key;
 	INIT_HLIST_NODE(&tr->hlist);
 	hlist_add_head(&tr->hlist, head);
@@ -99,9 +82,6 @@ static struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
 	mutex_init(&tr->mutex);
 	for (i = 0; i < BPF_TRAMP_MAX; i++)
 		INIT_HLIST_HEAD(&tr->progs_hlist[i]);
-	tr->image = image;
-	INIT_LIST_HEAD_RCU(&tr->ksym.lnode);
-	bpf_trampoline_ksym_add(tr);
 out:
 	mutex_unlock(&trampoline_mutex);
 	return tr;
@@ -185,10 +165,142 @@ bpf_trampoline_get_progs(const struct bpf_trampoline *tr, int *total)
 	return tprogs;
 }
 
+static void __bpf_tramp_image_put_deferred(struct work_struct *work)
+{
+	struct bpf_tramp_image *im;
+
+	im = container_of(work, struct bpf_tramp_image, work);
+	bpf_image_ksym_del(&im->ksym);
+	bpf_jit_free_exec(im->image);
+	bpf_jit_uncharge_modmem(1);
+	percpu_ref_exit(&im->pcref);
+	kfree_rcu(im, rcu);
+}
+
+/* callback, fexit step 3 or fentry step 2 */
+static void __bpf_tramp_image_put_rcu(struct rcu_head *rcu)
+{
+	struct bpf_tramp_image *im;
+
+	im = container_of(rcu, struct bpf_tramp_image, rcu);
+	INIT_WORK(&im->work, __bpf_tramp_image_put_deferred);
+	schedule_work(&im->work);
+}
+
+/* callback, fexit step 2. Called after percpu_ref_kill confirms. */
+static void __bpf_tramp_image_release(struct percpu_ref *pcref)
+{
+	struct bpf_tramp_image *im;
+
+	im = container_of(pcref, struct bpf_tramp_image, pcref);
+	call_rcu_tasks(&im->rcu, __bpf_tramp_image_put_rcu);
+}
+
+/* callback, fexit or fentry step 1 */
+static void __bpf_tramp_image_put_rcu_tasks(struct rcu_head *rcu)
+{
+	struct bpf_tramp_image *im;
+
+	im = container_of(rcu, struct bpf_tramp_image, rcu);
+	if (im->ip_after_call)
+		/* the case of fmod_ret/fexit trampoline and CONFIG_PREEMPTION=y */
+		percpu_ref_kill(&im->pcref);
+	else
+		/* the case of fentry trampoline */
+		call_rcu_tasks(&im->rcu, __bpf_tramp_image_put_rcu);
+}
+
+static void bpf_tramp_image_put(struct bpf_tramp_image *im)
+{
+	/* The trampoline image that calls original function is using:
+	 * rcu_read_lock_trace to protect sleepable bpf progs
+	 * rcu_read_lock to protect normal bpf progs
+	 * percpu_ref to protect trampoline itself
+	 * rcu tasks to protect trampoline asm not covered by percpu_ref
+	 * (which are few asm insns before __bpf_tramp_enter and
+	 *  after __bpf_tramp_exit)
+	 *
+	 * The trampoline is unreachable before bpf_tramp_image_put().
+	 *
+	 * First, patch the trampoline to avoid calling into fexit progs.
+	 * The progs will be freed even if the original function is still
+	 * executing or sleeping.
+	 * In case of CONFIG_PREEMPT=y use call_rcu_tasks() to wait on
+	 * first few asm instructions to execute and call into
+	 * __bpf_tramp_enter->percpu_ref_get.
+	 * Then use percpu_ref_kill to wait for the trampoline and the original
+	 * function to finish.
+	 * Then use call_rcu_tasks() to make sure few asm insns in
+	 * the trampoline epilogue are done as well.
+	 *
+	 * In !PREEMPT case the task that got interrupted in the first asm
+	 * insns won't go through an RCU quiescent state which the
+	 * percpu_ref_kill will be waiting for. Hence the first
+	 * call_rcu_tasks() is not necessary.
+	 */
+	if (im->ip_after_call) {
+		int err = bpf_arch_text_poke(im->ip_after_call, BPF_MOD_JUMP,
+					     NULL, im->ip_epilogue);
+		WARN_ON(err);
+		if (IS_ENABLED(CONFIG_PREEMPTION))
+			call_rcu_tasks(&im->rcu, __bpf_tramp_image_put_rcu_tasks);
+		else
+			percpu_ref_kill(&im->pcref);
+		return;
+	}
+
+	/* The trampoline without fexit and fmod_ret progs doesn't call original
+	 * function and doesn't use percpu_ref.
+	 * Use call_rcu_tasks_trace() to wait for sleepable progs to finish.
+	 * Then use call_rcu_tasks() to wait for the rest of trampoline asm
+	 * and normal progs.
+	 */
+	call_rcu_tasks_trace(&im->rcu, __bpf_tramp_image_put_rcu_tasks);
+}
+
+static struct bpf_tramp_image *bpf_tramp_image_alloc(u64 key, u32 idx)
+{
+	struct bpf_tramp_image *im;
+	struct bpf_ksym *ksym;
+	void *image;
+	int err = -ENOMEM;
+
+	im = kzalloc(sizeof(*im), GFP_KERNEL);
+	if (!im)
+		goto out;
+
+	err = bpf_jit_charge_modmem(1);
+	if (err)
+		goto out_free_im;
+
+	err = -ENOMEM;
+	im->image = image = bpf_jit_alloc_exec_page();
+	if (!image)
+		goto out_uncharge;
+
+	err = percpu_ref_init(&im->pcref, __bpf_tramp_image_release, 0, GFP_KERNEL);
+	if (err)
+		goto out_free_image;
+
+	ksym = &im->ksym;
+	INIT_LIST_HEAD_RCU(&ksym->lnode);
+	snprintf(ksym->name, KSYM_NAME_LEN, "bpf_trampoline_%llu_%u", key, idx);
+	bpf_image_ksym_add(image, ksym);
+	return im;
+
+out_free_image:
+	bpf_jit_free_exec(im->image);
+out_uncharge:
+	bpf_jit_uncharge_modmem(1);
+out_free_im:
+	kfree(im);
+out:
+	return ERR_PTR(err);
+}
+
 static int bpf_trampoline_update(struct bpf_trampoline *tr)
 {
-	void *old_image = tr->image + ((tr->selector + 1) & 1) * PAGE_SIZE/2;
-	void *new_image = tr->image + (tr->selector & 1) * PAGE_SIZE/2;
+	struct bpf_tramp_image *im;
 	struct bpf_tramp_progs *tprogs;
 	u32 flags = BPF_TRAMP_F_RESTORE_REGS;
 	int err, total;
@@ -198,41 +310,42 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr)
 		return PTR_ERR(tprogs);
 
 	if (total == 0) {
-		err = unregister_fentry(tr, old_image);
+		err = unregister_fentry(tr, tr->cur_image->image);
+		bpf_tramp_image_put(tr->cur_image);
+		tr->cur_image = NULL;
 		tr->selector = 0;
 		goto out;
 	}
 
+	im = bpf_tramp_image_alloc(tr->key, tr->selector);
+	if (IS_ERR(im)) {
+		err = PTR_ERR(im);
+		goto out;
+	}
+
 	if (tprogs[BPF_TRAMP_FEXIT].nr_progs ||
 	    tprogs[BPF_TRAMP_MODIFY_RETURN].nr_progs)
 		flags = BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_SKIP_FRAME;
 
-	/* Though the second half of trampoline page is unused a task could be
-	 * preempted in the middle of the first half of trampoline and two
-	 * updates to trampoline would change the code from underneath the
-	 * preempted task. Hence wait for tasks to voluntarily schedule or go
-	 * to userspace.
-	 * The same trampoline can hold both sleepable and non-sleepable progs.
-	 * synchronize_rcu_tasks_trace() is needed to make sure all sleepable
-	 * programs finish executing.
-	 * Wait for these two grace periods together.
-	 */
-	synchronize_rcu_mult(call_rcu_tasks, call_rcu_tasks_trace);
-
-	err = arch_prepare_bpf_trampoline(new_image, new_image + PAGE_SIZE / 2,
+	err = arch_prepare_bpf_trampoline(im, im->image, im->image + PAGE_SIZE,
 					  &tr->func.model, flags, tprogs,
 					  tr->func.addr);
 	if (err < 0)
 		goto out;
 
-	if (tr->selector)
+	WARN_ON(tr->cur_image && tr->selector == 0);
+	WARN_ON(!tr->cur_image && tr->selector);
+	if (tr->cur_image)
 		/* progs already running at this address */
-		err = modify_fentry(tr, old_image, new_image);
+		err = modify_fentry(tr, tr->cur_image->image, im->image);
 	else
 		/* first time registering */
-		err = register_fentry(tr, new_image);
+		err = register_fentry(tr, im->image);
 	if (err)
 		goto out;
+	if (tr->cur_image)
+		bpf_tramp_image_put(tr->cur_image);
+	tr->cur_image = im;
 	tr->selector++;
 out:
 	kfree(tprogs);
@@ -364,17 +477,12 @@ void bpf_trampoline_put(struct bpf_trampoline *tr)
 		goto out;
 	if (WARN_ON_ONCE(!hlist_empty(&tr->progs_hlist[BPF_TRAMP_FEXIT])))
 		goto out;
-	bpf_image_ksym_del(&tr->ksym);
-	/* This code will be executed when all bpf progs (both sleepable and
-	 * non-sleepable) went through
-	 * bpf_prog_put()->call_rcu[_tasks_trace]()->bpf_prog_free_deferred().
-	 * Hence no need for another synchronize_rcu_tasks_trace() here,
-	 * but synchronize_rcu_tasks() is still needed, since trampoline
-	 * may not have had any sleepable programs and we need to wait
-	 * for tasks to get out of trampoline code before freeing it.
+	/* This code will be executed even when the last bpf_tramp_image
+	 * is alive. All progs are detached from the trampoline and the
+	 * trampoline image is patched with jmp into epilogue to skip
+	 * fexit progs. The fentry-only trampoline will be freed via
+	 * multiple rcu callbacks.
 	 */
-	synchronize_rcu_tasks();
-	bpf_jit_free_exec(tr->image);
 	hlist_del(&tr->hlist);
 	kfree(tr);
 out:
@@ -478,8 +586,18 @@ void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start)
 	rcu_read_unlock_trace();
 }
 
+void notrace __bpf_tramp_enter(struct bpf_tramp_image *tr)
+{
+	percpu_ref_get(&tr->pcref);
+}
+
+void notrace __bpf_tramp_exit(struct bpf_tramp_image *tr)
+{
+	percpu_ref_put(&tr->pcref);
+}
+
 int __weak
-arch_prepare_bpf_trampoline(void *image, void *image_end,
+arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *image_end,
 			    const struct btf_func_model *m, u32 flags,
 			    struct bpf_tramp_progs *tprogs,
 			    void *orig_call)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e26c5170c953..210169c25ead 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -6045,10 +6045,14 @@ static int retrieve_ptr_limit(const struct bpf_reg_state *ptr_reg,
 {
 	bool mask_to_left = (opcode == BPF_ADD &&  off_is_neg) ||
 			    (opcode == BPF_SUB && !off_is_neg);
-	u32 off;
+	u32 off, max;
 
 	switch (ptr_reg->type) {
 	case PTR_TO_STACK:
+		/* Offset 0 is out-of-bounds, but acceptable start for the
+		 * left direction, see BPF_REG_FP.
+		 */
+		max = MAX_BPF_STACK + mask_to_left;
 		/* Indirect variable offset stack access is prohibited in
 		 * unprivileged mode so it's not handled here.
 		 */
@@ -6056,8 +6060,8 @@ static int retrieve_ptr_limit(const struct bpf_reg_state *ptr_reg,
 		if (mask_to_left)
 			*ptr_limit = MAX_BPF_STACK + off;
 		else
-			*ptr_limit = -off;
-		return 0;
+			*ptr_limit = -off - 1;
+		return *ptr_limit >= max ? -ERANGE : 0;
 	case PTR_TO_MAP_KEY:
 		/* Currently, this code is not exercised as the only use
 		 * is bpf_for_each_map_elem() helper which requires
@@ -6072,13 +6076,14 @@ static int retrieve_ptr_limit(const struct bpf_reg_state *ptr_reg,
 		}
 		return 0;
 	case PTR_TO_MAP_VALUE:
+		max = ptr_reg->map_ptr->value_size;
 		if (mask_to_left) {
 			*ptr_limit = ptr_reg->umax_value + ptr_reg->off;
 		} else {
 			off = ptr_reg->smin_value + ptr_reg->off;
-			*ptr_limit = ptr_reg->map_ptr->value_size - off;
+			*ptr_limit = ptr_reg->map_ptr->value_size - off - 1;
 		}
-		return 0;
+		return *ptr_limit >= max ? -ERANGE : 0;
 	default:
 		return -EINVAL;
 	}
@@ -6131,6 +6136,7 @@ static int sanitize_ptr_alu(struct bpf_verifier_env *env,
 	u32 alu_state, alu_limit;
 	struct bpf_reg_state tmp;
 	bool ret;
+	int err;
 
 	if (can_skip_alu_sanitation(env, insn))
 		return 0;
@@ -6146,10 +6152,13 @@ static int sanitize_ptr_alu(struct bpf_verifier_env *env,
 	alu_state |= ptr_is_dst_reg ?
 		     BPF_ALU_SANITIZE_SRC : BPF_ALU_SANITIZE_DST;
 
-	if (retrieve_ptr_limit(ptr_reg, &alu_limit, opcode, off_is_neg))
-		return 0;
-	if (update_alu_sanitation_state(aux, alu_state, alu_limit))
-		return -EACCES;
+	err = retrieve_ptr_limit(ptr_reg, &alu_limit, opcode, off_is_neg);
+	if (err < 0)
+		return err;
+
+	err = update_alu_sanitation_state(aux, alu_state, alu_limit);
+	if (err < 0)
+		return err;
 do_sim:
 	/* Simulate and find potential out-of-bounds access under
 	 * speculative execution from truncation as a result of
@@ -6301,7 +6310,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
 	case BPF_ADD:
 		ret = sanitize_ptr_alu(env, insn, ptr_reg, dst_reg, smin_val < 0);
 		if (ret < 0) {
-			verbose(env, "R%d tried to add from different maps or paths\n", dst);
+			verbose(env, "R%d tried to add from different maps, paths, or prohibited types\n", dst);
 			return ret;
 		}
 		/* We can take a fixed offset as long as it doesn't overflow
@@ -6356,7 +6365,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
 	case BPF_SUB:
 		ret = sanitize_ptr_alu(env, insn, ptr_reg, dst_reg, smin_val < 0);
 		if (ret < 0) {
-			verbose(env, "R%d tried to sub from different maps or paths\n", dst);
+			verbose(env, "R%d tried to sub from different maps, paths, or prohibited types\n", dst);
 			return ret;
 		}
 		if (dst_reg == off_reg) {
@@ -9276,6 +9285,10 @@ static int check_btf_info(struct bpf_verifier_env *env,
 	btf = btf_get_by_fd(attr->prog_btf_fd);
 	if (IS_ERR(btf))
 		return PTR_ERR(btf);
+	if (btf_is_kernel(btf)) {
+		btf_put(btf);
+		return -EACCES;
+	}
 	env->prog->aux->btf = btf;
 
 	err = check_btf_func(env, attr, uattr);
@@ -11915,7 +11928,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
 			off_reg = issrc ? insn->src_reg : insn->dst_reg;
 			if (isneg)
 				*patch++ = BPF_ALU64_IMM(BPF_MUL, off_reg, -1);
-			*patch++ = BPF_MOV32_IMM(BPF_REG_AX, aux->alu_limit - 1);
+			*patch++ = BPF_MOV32_IMM(BPF_REG_AX, aux->alu_limit);
 			*patch++ = BPF_ALU64_REG(BPF_SUB, BPF_REG_AX, off_reg);
 			*patch++ = BPF_ALU64_REG(BPF_OR, BPF_REG_AX, off_reg);
 			*patch++ = BPF_ALU64_IMM(BPF_NEG, BPF_REG_AX, 0);
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 0aeca5f3c0ac..03db40f6cba9 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -386,6 +386,7 @@ static DEFINE_MUTEX(perf_sched_mutex);
 static atomic_t perf_sched_count;
 
 static DEFINE_PER_CPU(atomic_t, perf_cgroup_events);
+static DEFINE_PER_CPU(int, perf_sched_cb_usages);
 static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events);
 
 static atomic_t nr_mmap_events __read_mostly;
@@ -3461,11 +3462,16 @@ unlock:
 	}
 }
 
+static DEFINE_PER_CPU(struct list_head, sched_cb_list);
+
 void perf_sched_cb_dec(struct pmu *pmu)
 {
 	struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
 
-	--cpuctx->sched_cb_usage;
+	this_cpu_dec(perf_sched_cb_usages);
+
+	if (!--cpuctx->sched_cb_usage)
+		list_del(&cpuctx->sched_cb_entry);
 }
 
 
@@ -3473,7 +3479,10 @@ void perf_sched_cb_inc(struct pmu *pmu)
 {
 	struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
 
-	cpuctx->sched_cb_usage++;
+	if (!cpuctx->sched_cb_usage++)
+		list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list));
+
+	this_cpu_inc(perf_sched_cb_usages);
 }
 
 /*
@@ -3502,6 +3511,24 @@ static void __perf_pmu_sched_task(struct perf_cpu_context *cpuctx, bool sched_in
 	perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
 }
 
+static void perf_pmu_sched_task(struct task_struct *prev,
+				struct task_struct *next,
+				bool sched_in)
+{
+	struct perf_cpu_context *cpuctx;
+
+	if (prev == next)
+		return;
+
+	list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) {
+		/* will be handled in perf_event_context_sched_in/out */
+		if (cpuctx->task_ctx)
+			continue;
+
+		__perf_pmu_sched_task(cpuctx, sched_in);
+	}
+}
+
 static void perf_event_switch(struct task_struct *task,
 			      struct task_struct *next_prev, bool sched_in);
 
@@ -3524,6 +3551,9 @@ void __perf_event_task_sched_out(struct task_struct *task,
 {
 	int ctxn;
 
+	if (__this_cpu_read(perf_sched_cb_usages))
+		perf_pmu_sched_task(task, next, false);
+
 	if (atomic_read(&nr_switch_events))
 		perf_event_switch(task, next, false);
 
@@ -3832,6 +3862,9 @@ void __perf_event_task_sched_in(struct task_struct *prev,
 
 	if (atomic_read(&nr_switch_events))
 		perf_event_switch(task, prev, true);
+
+	if (__this_cpu_read(perf_sched_cb_usages))
+		perf_pmu_sched_task(prev, task, true);
 }
 
 static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
@@ -4656,7 +4689,7 @@ static void unaccount_event(struct perf_event *event)
 	if (event->parent)
 		return;
 
-	if (event->attach_state & PERF_ATTACH_TASK)
+	if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB))
 		dec = true;
 	if (event->attr.mmap || event->attr.mmap_data)
 		atomic_dec(&nr_mmap_events);
@@ -11175,7 +11208,7 @@ static void account_event(struct perf_event *event)
 	if (event->parent)
 		return;
 
-	if (event->attach_state & PERF_ATTACH_TASK)
+	if (event->attach_state & (PERF_ATTACH_TASK | PERF_ATTACH_SCHED_CB))
 		inc = true;
 	if (event->attr.mmap || event->attr.mmap_data)
 		atomic_inc(&nr_mmap_events);
@@ -12972,6 +13005,7 @@ static void __init perf_event_init_all_cpus(void)
 #ifdef CONFIG_CGROUP_PERF
 		INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu));
 #endif
+		INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu));
 	}
 }
 
diff --git a/kernel/fork.c b/kernel/fork.c
index b94391a58708..50209691f21a 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -996,6 +996,13 @@ static void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
 #endif
 }
 
+static void mm_init_pasid(struct mm_struct *mm)
+{
+#ifdef CONFIG_IOMMU_SUPPORT
+	mm->pasid = INIT_PASID;
+#endif
+}
+
 static void mm_init_uprobes_state(struct mm_struct *mm)
 {
 #ifdef CONFIG_UPROBES
@@ -1026,6 +1033,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 	mm_init_cpumask(mm);
 	mm_init_aio(mm);
 	mm_init_owner(mm, p);
+	mm_init_pasid(mm);
 	RCU_INIT_POINTER(mm->exe_file, NULL);
 	mmu_notifier_subscriptions_init(mm);
 	init_tlb_flush_pending(mm);
diff --git a/kernel/freezer.c b/kernel/freezer.c
index dc520f01f99d..1a2d57d1327c 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -134,7 +134,7 @@ bool freeze_task(struct task_struct *p)
 		return false;
 	}
 
-	if (!(p->flags & PF_KTHREAD))
+	if (!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))
 		fake_signal_wake_up(p);
 	else
 		wake_up_state(p, TASK_INTERRUPTIBLE);
diff --git a/kernel/futex.c b/kernel/futex.c
index e68db7745039..00febd6dea9c 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2728,14 +2728,13 @@ retry:
 		goto out;
 
 	restart = &current->restart_block;
-	restart->fn = futex_wait_restart;
 	restart->futex.uaddr = uaddr;
 	restart->futex.val = val;
 	restart->futex.time = *abs_time;
 	restart->futex.bitset = bitset;
 	restart->futex.flags = flags | FLAGS_HAS_TIMEOUT;
 
-	ret = -ERESTART_RESTARTBLOCK;
+	ret = set_restart_fn(restart, futex_wait_restart);
 
 out:
 	if (to) {
diff --git a/kernel/gcov/clang.c b/kernel/gcov/clang.c
index c94b820a1b62..8743150db2ac 100644
--- a/kernel/gcov/clang.c
+++ b/kernel/gcov/clang.c
@@ -75,7 +75,9 @@ struct gcov_fn_info {
 
 	u32 num_counters;
 	u64 *counters;
+#if CONFIG_CLANG_VERSION < 110000
 	const char *function_name;
+#endif
 };
 
 static struct gcov_info *current_info;
@@ -105,6 +107,7 @@ void llvm_gcov_init(llvm_gcov_callback writeout, llvm_gcov_callback flush)
 }
 EXPORT_SYMBOL(llvm_gcov_init);
 
+#if CONFIG_CLANG_VERSION < 110000
 void llvm_gcda_start_file(const char *orig_filename, const char version[4],
 		u32 checksum)
 {
@@ -113,7 +116,17 @@ void llvm_gcda_start_file(const char *orig_filename, const char version[4],
 	current_info->checksum = checksum;
 }
 EXPORT_SYMBOL(llvm_gcda_start_file);
+#else
+void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum)
+{
+	current_info->filename = orig_filename;
+	current_info->version = version;
+	current_info->checksum = checksum;
+}
+EXPORT_SYMBOL(llvm_gcda_start_file);
+#endif
 
+#if CONFIG_CLANG_VERSION < 110000
 void llvm_gcda_emit_function(u32 ident, const char *function_name,
 		u32 func_checksum, u8 use_extra_checksum, u32 cfg_checksum)
 {
@@ -133,6 +146,24 @@ void llvm_gcda_emit_function(u32 ident, const char *function_name,
 	list_add_tail(&info->head, &current_info->functions);
 }
 EXPORT_SYMBOL(llvm_gcda_emit_function);
+#else
+void llvm_gcda_emit_function(u32 ident, u32 func_checksum,
+		u8 use_extra_checksum, u32 cfg_checksum)
+{
+	struct gcov_fn_info *info = kzalloc(sizeof(*info), GFP_KERNEL);
+
+	if (!info)
+		return;
+
+	INIT_LIST_HEAD(&info->head);
+	info->ident = ident;
+	info->checksum = func_checksum;
+	info->use_extra_checksum = use_extra_checksum;
+	info->cfg_checksum = cfg_checksum;
+	list_add_tail(&info->head, &current_info->functions);
+}
+EXPORT_SYMBOL(llvm_gcda_emit_function);
+#endif
 
 void llvm_gcda_emit_arcs(u32 num_counters, u64 *counters)
 {
@@ -295,6 +326,7 @@ void gcov_info_add(struct gcov_info *dst, struct gcov_info *src)
 	}
 }
 
+#if CONFIG_CLANG_VERSION < 110000
 static struct gcov_fn_info *gcov_fn_info_dup(struct gcov_fn_info *fn)
 {
 	size_t cv_size; /* counter values size */
@@ -322,6 +354,28 @@ err_name:
 	kfree(fn_dup);
 	return NULL;
 }
+#else
+static struct gcov_fn_info *gcov_fn_info_dup(struct gcov_fn_info *fn)
+{
+	size_t cv_size; /* counter values size */
+	struct gcov_fn_info *fn_dup = kmemdup(fn, sizeof(*fn),
+			GFP_KERNEL);
+	if (!fn_dup)
+		return NULL;
+	INIT_LIST_HEAD(&fn_dup->head);
+
+	cv_size = fn->num_counters * sizeof(fn->counters[0]);
+	fn_dup->counters = vmalloc(cv_size);
+	if (!fn_dup->counters) {
+		kfree(fn_dup);
+		return NULL;
+	}
+
+	memcpy(fn_dup->counters, fn->counters, cv_size);
+
+	return fn_dup;
+}
+#endif
 
 /**
  * gcov_info_dup - duplicate profiling data set
@@ -362,6 +416,7 @@ err:
  * gcov_info_free - release memory for profiling data set duplicate
  * @info: profiling data set duplicate to free
  */
+#if CONFIG_CLANG_VERSION < 110000
 void gcov_info_free(struct gcov_info *info)
 {
 	struct gcov_fn_info *fn, *tmp;
@@ -375,6 +430,20 @@ void gcov_info_free(struct gcov_info *info)
 	kfree(info->filename);
 	kfree(info);
 }
+#else
+void gcov_info_free(struct gcov_info *info)
+{
+	struct gcov_fn_info *fn, *tmp;
+
+	list_for_each_entry_safe(fn, tmp, &info->functions, head) {
+		vfree(fn->counters);
+		list_del(&fn->head);
+		kfree(fn);
+	}
+	kfree(info->filename);
+	kfree(info);
+}
+#endif
 
 #define ITER_STRIDE	PAGE_SIZE
 
diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
index 48006608baf0..40880c350b95 100644
--- a/kernel/irq/irq_sim.c
+++ b/kernel/irq/irq_sim.c
@@ -159,7 +159,7 @@ static const struct irq_domain_ops irq_sim_domain_ops = {
  * irq_domain_create_sim - Create a new interrupt simulator irq_domain and
  *                         allocate a range of dummy interrupts.
  *
- * @fnode:      struct fwnode_handle to be associated with this domain.
+ * @fwnode:     struct fwnode_handle to be associated with this domain.
  * @num_irqs:   Number of interrupts to allocate.
  *
  * On success: return a new irq_domain object.
@@ -228,7 +228,7 @@ static void devm_irq_domain_release_sim(struct device *dev, void *res)
  *                              a managed device.
  *
  * @dev:        Device to initialize the simulator object for.
- * @fnode:      struct fwnode_handle to be associated with this domain.
+ * @fwnode:     struct fwnode_handle to be associated with this domain.
  * @num_irqs:   Number of interrupts to allocate
  *
  * On success: return a new irq_domain object.
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 288151393a06..d10ab1d689d5 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1898,16 +1898,15 @@ DEFINE_SHOW_ATTRIBUTE(irq_domain_debug);
 
 static void debugfs_add_domain_dir(struct irq_domain *d)
 {
-	if (!d->name || !domain_dir || d->debugfs_file)
+	if (!d->name || !domain_dir)
 		return;
-	d->debugfs_file = debugfs_create_file(d->name, 0444, domain_dir, d,
-					      &irq_domain_debug_fops);
+	debugfs_create_file(d->name, 0444, domain_dir, d,
+			    &irq_domain_debug_fops);
 }
 
 static void debugfs_remove_domain_dir(struct irq_domain *d)
 {
-	debugfs_remove(d->debugfs_file);
-	d->debugfs_file = NULL;
+	debugfs_remove(debugfs_lookup(d->name, domain_dir));
 }
 
 void __init irq_domain_debugfs_init(struct dentry *root)
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index dec3f73e8db9..21ea370fccda 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1142,11 +1142,15 @@ irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
 	irqreturn_t ret;
 
 	local_bh_disable();
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_irq_disable();
 	ret = action->thread_fn(action->irq, action->dev_id);
 	if (ret == IRQ_HANDLED)
 		atomic_inc(&desc->threads_handled);
 
 	irq_finalize_oneshot(desc, action);
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_irq_enable();
 	local_bh_enable();
 	return ret;
 }
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index c6a39d662935..ba39fbb1f8e7 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -407,6 +407,14 @@ static bool jump_label_can_update(struct jump_entry *entry, bool init)
 		return false;
 
 	if (!kernel_text_address(jump_entry_code(entry))) {
+		/*
+		 * This skips patching built-in __exit, which
+		 * is part of init_section_contains() but is
+		 * not part of kernel_text_address().
+		 *
+		 * Skipping built-in __exit is fine since it
+		 * will never be executed.
+		 */
 		WARN_ONCE(!jump_entry_is_init(entry),
 			  "can't patch jump_label at %pS",
 			  (void *)jump_entry_code(entry));
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index adb935090768..622ebdfcd083 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -626,7 +626,7 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock)
  */
 static __always_inline bool
 mutex_optimistic_spin(struct mutex *lock, struct ww_acquire_ctx *ww_ctx,
-		      const bool use_ww_ctx, struct mutex_waiter *waiter)
+		      struct mutex_waiter *waiter)
 {
 	if (!waiter) {
 		/*
@@ -702,7 +702,7 @@ fail:
 #else
 static __always_inline bool
 mutex_optimistic_spin(struct mutex *lock, struct ww_acquire_ctx *ww_ctx,
-		      const bool use_ww_ctx, struct mutex_waiter *waiter)
+		      struct mutex_waiter *waiter)
 {
 	return false;
 }
@@ -922,6 +922,9 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 	struct ww_mutex *ww;
 	int ret;
 
+	if (!use_ww_ctx)
+		ww_ctx = NULL;
+
 	might_sleep();
 
 #ifdef CONFIG_DEBUG_MUTEXES
@@ -929,7 +932,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 #endif
 
 	ww = container_of(lock, struct ww_mutex, base);
-	if (use_ww_ctx && ww_ctx) {
+	if (ww_ctx) {
 		if (unlikely(ww_ctx == READ_ONCE(ww->ctx)))
 			return -EALREADY;
 
@@ -946,10 +949,10 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 	mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip);
 
 	if (__mutex_trylock(lock) ||
-	    mutex_optimistic_spin(lock, ww_ctx, use_ww_ctx, NULL)) {
+	    mutex_optimistic_spin(lock, ww_ctx, NULL)) {
 		/* got the lock, yay! */
 		lock_acquired(&lock->dep_map, ip);
-		if (use_ww_ctx && ww_ctx)
+		if (ww_ctx)
 			ww_mutex_set_context_fastpath(ww, ww_ctx);
 		preempt_enable();
 		return 0;
@@ -960,7 +963,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 	 * After waiting to acquire the wait_lock, try again.
 	 */
 	if (__mutex_trylock(lock)) {
-		if (use_ww_ctx && ww_ctx)
+		if (ww_ctx)
 			__ww_mutex_check_waiters(lock, ww_ctx);
 
 		goto skip_wait;
@@ -1013,7 +1016,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 			goto err;
 		}
 
-		if (use_ww_ctx && ww_ctx) {
+		if (ww_ctx) {
 			ret = __ww_mutex_check_kill(lock, &waiter, ww_ctx);
 			if (ret)
 				goto err;
@@ -1026,7 +1029,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 		 * ww_mutex needs to always recheck its position since its waiter
 		 * list is not FIFO ordered.
 		 */
-		if ((use_ww_ctx && ww_ctx) || !first) {
+		if (ww_ctx || !first) {
 			first = __mutex_waiter_is_first(lock, &waiter);
 			if (first)
 				__mutex_set_flag(lock, MUTEX_FLAG_HANDOFF);
@@ -1039,7 +1042,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 		 * or we must see its unlock and acquire.
 		 */
 		if (__mutex_trylock(lock) ||
-		    (first && mutex_optimistic_spin(lock, ww_ctx, use_ww_ctx, &waiter)))
+		    (first && mutex_optimistic_spin(lock, ww_ctx, &waiter)))
 			break;
 
 		spin_lock(&lock->wait_lock);
@@ -1048,7 +1051,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 acquired:
 	__set_current_state(TASK_RUNNING);
 
-	if (use_ww_ctx && ww_ctx) {
+	if (ww_ctx) {
 		/*
 		 * Wound-Wait; we stole the lock (!first_waiter), check the
 		 * waiters as anyone might want to wound us.
@@ -1068,7 +1071,7 @@ skip_wait:
 	/* got the lock - cleanup and rejoice! */
 	lock_acquired(&lock->dep_map, ip);
 
-	if (use_ww_ctx && ww_ctx)
+	if (ww_ctx)
 		ww_mutex_lock_acquired(ww, ww_ctx);
 
 	spin_unlock(&lock->wait_lock);
diff --git a/kernel/reboot.c b/kernel/reboot.c
index eb1b15850761..a6ad5eb2fa73 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -244,8 +244,6 @@ void migrate_to_reboot_cpu(void)
 void kernel_restart(char *cmd)
 {
 	kernel_restart_prepare(cmd);
-	if (pm_power_off_prepare)
-		pm_power_off_prepare();
 	migrate_to_reboot_cpu();
 	syscore_shutdown();
 	if (!cmd)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ca2bb629595f..98191218d891 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1862,8 +1862,13 @@ struct migration_arg {
 	struct set_affinity_pending	*pending;
 };
 
+/*
+ * @refs: number of wait_for_completion()
+ * @stop_pending: is @stop_work in use
+ */
 struct set_affinity_pending {
 	refcount_t		refs;
+	unsigned int		stop_pending;
 	struct completion	done;
 	struct cpu_stop_work	stop_work;
 	struct migration_arg	arg;
@@ -1898,8 +1903,8 @@ static struct rq *__migrate_task(struct rq *rq, struct rq_flags *rf,
  */
 static int migration_cpu_stop(void *data)
 {
-	struct set_affinity_pending *pending;
 	struct migration_arg *arg = data;
+	struct set_affinity_pending *pending = arg->pending;
 	struct task_struct *p = arg->task;
 	int dest_cpu = arg->dest_cpu;
 	struct rq *rq = this_rq();
@@ -1921,7 +1926,6 @@ static int migration_cpu_stop(void *data)
 	raw_spin_lock(&p->pi_lock);
 	rq_lock(rq, &rf);
 
-	pending = p->migration_pending;
 	/*
 	 * If task_rq(p) != rq, it cannot be migrated here, because we're
 	 * holding rq->lock, if p->on_rq == 0 it cannot get enqueued because
@@ -1932,21 +1936,14 @@ static int migration_cpu_stop(void *data)
 			goto out;
 
 		if (pending) {
-			p->migration_pending = NULL;
+			if (p->migration_pending == pending)
+				p->migration_pending = NULL;
 			complete = true;
 		}
 
-		/* migrate_enable() --  we must not race against SCA */
 		if (dest_cpu < 0) {
-			/*
-			 * When this was migrate_enable() but we no longer
-			 * have a @pending, a concurrent SCA 'fixed' things
-			 * and we should be valid again. Nothing to do.
-			 */
-			if (!pending) {
-				WARN_ON_ONCE(!cpumask_test_cpu(task_cpu(p), &p->cpus_mask));
+			if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask))
 				goto out;
-			}
 
 			dest_cpu = cpumask_any_distribute(&p->cpus_mask);
 		}
@@ -1956,7 +1953,14 @@ static int migration_cpu_stop(void *data)
 		else
 			p->wake_cpu = dest_cpu;
 
-	} else if (dest_cpu < 0 || pending) {
+		/*
+		 * XXX __migrate_task() can fail, at which point we might end
+		 * up running on a dodgy CPU, AFAICT this can only happen
+		 * during CPU hotplug, at which point we'll get pushed out
+		 * anyway, so it's probably not a big deal.
+		 */
+
+	} else if (pending) {
 		/*
 		 * This happens when we get migrated between migrate_enable()'s
 		 * preempt_enable() and scheduling the stopper task. At that
@@ -1971,43 +1975,32 @@ static int migration_cpu_stop(void *data)
 		 * ->pi_lock, so the allowed mask is stable - if it got
 		 * somewhere allowed, we're done.
 		 */
-		if (pending && cpumask_test_cpu(task_cpu(p), p->cpus_ptr)) {
-			p->migration_pending = NULL;
+		if (cpumask_test_cpu(task_cpu(p), p->cpus_ptr)) {
+			if (p->migration_pending == pending)
+				p->migration_pending = NULL;
 			complete = true;
 			goto out;
 		}
 
 		/*
-		 * When this was migrate_enable() but we no longer have an
-		 * @pending, a concurrent SCA 'fixed' things and we should be
-		 * valid again. Nothing to do.
-		 */
-		if (!pending) {
-			WARN_ON_ONCE(!cpumask_test_cpu(task_cpu(p), &p->cpus_mask));
-			goto out;
-		}
-
-		/*
 		 * When migrate_enable() hits a rq mis-match we can't reliably
 		 * determine is_migration_disabled() and so have to chase after
 		 * it.
 		 */
+		WARN_ON_ONCE(!pending->stop_pending);
 		task_rq_unlock(rq, p, &rf);
 		stop_one_cpu_nowait(task_cpu(p), migration_cpu_stop,
 				    &pending->arg, &pending->stop_work);
 		return 0;
 	}
 out:
+	if (pending)
+		pending->stop_pending = false;
 	task_rq_unlock(rq, p, &rf);
 
 	if (complete)
 		complete_all(&pending->done);
 
-	/* For pending->{arg,stop_work} */
-	pending = arg->pending;
-	if (pending && refcount_dec_and_test(&pending->refs))
-		wake_up_var(&pending->refs);
-
 	return 0;
 }
 
@@ -2194,11 +2187,7 @@ static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flag
 			    int dest_cpu, unsigned int flags)
 {
 	struct set_affinity_pending my_pending = { }, *pending = NULL;
-	struct migration_arg arg = {
-		.task = p,
-		.dest_cpu = dest_cpu,
-	};
-	bool complete = false;
+	bool stop_pending, complete = false;
 
 	/* Can the task run on the task's current CPU? If so, we're done */
 	if (cpumask_test_cpu(task_cpu(p), &p->cpus_mask)) {
@@ -2210,12 +2199,16 @@ static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flag
 			push_task = get_task_struct(p);
 		}
 
+		/*
+		 * If there are pending waiters, but no pending stop_work,
+		 * then complete now.
+		 */
 		pending = p->migration_pending;
-		if (pending) {
-			refcount_inc(&pending->refs);
+		if (pending && !pending->stop_pending) {
 			p->migration_pending = NULL;
 			complete = true;
 		}
+
 		task_rq_unlock(rq, p, rf);
 
 		if (push_task) {
@@ -2224,7 +2217,7 @@ static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flag
 		}
 
 		if (complete)
-			goto do_complete;
+			complete_all(&pending->done);
 
 		return 0;
 	}
@@ -2235,6 +2228,12 @@ static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flag
 			/* Install the request */
 			refcount_set(&my_pending.refs, 1);
 			init_completion(&my_pending.done);
+			my_pending.arg = (struct migration_arg) {
+				.task = p,
+				.dest_cpu = -1,		/* any */
+				.pending = &my_pending,
+			};
+
 			p->migration_pending = &my_pending;
 		} else {
 			pending = p->migration_pending;
@@ -2259,45 +2258,41 @@ static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flag
 		return -EINVAL;
 	}
 
-	if (flags & SCA_MIGRATE_ENABLE) {
-
-		refcount_inc(&pending->refs); /* pending->{arg,stop_work} */
-		p->migration_flags &= ~MDF_PUSH;
-		task_rq_unlock(rq, p, rf);
-
-		pending->arg = (struct migration_arg) {
-			.task = p,
-			.dest_cpu = -1,
-			.pending = pending,
-		};
-
-		stop_one_cpu_nowait(cpu_of(rq), migration_cpu_stop,
-				    &pending->arg, &pending->stop_work);
-
-		return 0;
-	}
-
 	if (task_running(rq, p) || p->state == TASK_WAKING) {
 		/*
-		 * Lessen races (and headaches) by delegating
-		 * is_migration_disabled(p) checks to the stopper, which will
-		 * run on the same CPU as said p.
+		 * MIGRATE_ENABLE gets here because 'p == current', but for
+		 * anything else we cannot do is_migration_disabled(), punt
+		 * and have the stopper function handle it all race-free.
 		 */
+		stop_pending = pending->stop_pending;
+		if (!stop_pending)
+			pending->stop_pending = true;
+
+		if (flags & SCA_MIGRATE_ENABLE)
+			p->migration_flags &= ~MDF_PUSH;
+
 		task_rq_unlock(rq, p, rf);
-		stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
 
+		if (!stop_pending) {
+			stop_one_cpu_nowait(cpu_of(rq), migration_cpu_stop,
+					    &pending->arg, &pending->stop_work);
+		}
+
+		if (flags & SCA_MIGRATE_ENABLE)
+			return 0;
 	} else {
 
 		if (!is_migration_disabled(p)) {
 			if (task_on_rq_queued(p))
 				rq = move_queued_task(rq, rf, p, dest_cpu);
 
-			p->migration_pending = NULL;
-			complete = true;
+			if (!pending->stop_pending) {
+				p->migration_pending = NULL;
+				complete = true;
+			}
 		}
 		task_rq_unlock(rq, p, rf);
 
-do_complete:
 		if (complete)
 			complete_all(&pending->done);
 	}
@@ -2305,7 +2300,7 @@ do_complete:
 	wait_for_completion(&pending->done);
 
 	if (refcount_dec_and_test(&pending->refs))
-		wake_up_var(&pending->refs);
+		wake_up_var(&pending->refs); /* No UaF, just an address */
 
 	/*
 	 * Block the original owner of &pending until all subsequent callers
@@ -2313,6 +2308,9 @@ do_complete:
 	 */
 	wait_var_event(&my_pending.refs, !refcount_read(&my_pending.refs));
 
+	/* ARGH */
+	WARN_ON_ONCE(my_pending.stop_pending);
+
 	return 0;
 }
 
diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c
index acdae625c636..b5add64d9698 100644
--- a/kernel/sched/membarrier.c
+++ b/kernel/sched/membarrier.c
@@ -471,9 +471,7 @@ static int sync_runqueues_membarrier_state(struct mm_struct *mm)
 	}
 	rcu_read_unlock();
 
-	preempt_disable();
-	smp_call_function_many(tmpmask, ipi_sync_rq_state, mm, 1);
-	preempt_enable();
+	on_each_cpu_mask(tmpmask, ipi_sync_rq_state, mm, true);
 
 	free_cpumask_var(tmpmask);
 	cpus_read_unlock();
diff --git a/kernel/signal.c b/kernel/signal.c
index ba4d1ef39a9e..f2a1b898da29 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -288,7 +288,8 @@ bool task_set_jobctl_pending(struct task_struct *task, unsigned long mask)
 			JOBCTL_STOP_SIGMASK | JOBCTL_TRAPPING));
 	BUG_ON((mask & JOBCTL_TRAPPING) && !(mask & JOBCTL_PENDING_MASK));
 
-	if (unlikely(fatal_signal_pending(task) || (task->flags & PF_EXITING)))
+	if (unlikely(fatal_signal_pending(task) ||
+		     (task->flags & (PF_EXITING | PF_IO_WORKER))))
 		return false;
 
 	if (mask & JOBCTL_STOP_SIGMASK)
@@ -833,6 +834,9 @@ static int check_kill_permission(int sig, struct kernel_siginfo *info,
 
 	if (!valid_signal(sig))
 		return -EINVAL;
+	/* PF_IO_WORKER threads don't take any signals */
+	if (t->flags & PF_IO_WORKER)
+		return -ESRCH;
 
 	if (!si_fromuser(info))
 		return 0;
diff --git a/kernel/static_call.c b/kernel/static_call.c
index 6906c6ec4c97..2c5950b0b90e 100644
--- a/kernel/static_call.c
+++ b/kernel/static_call.c
@@ -35,27 +35,30 @@ static inline void *static_call_addr(struct static_call_site *site)
 	return (void *)((long)site->addr + (long)&site->addr);
 }
 
+static inline unsigned long __static_call_key(const struct static_call_site *site)
+{
+	return (long)site->key + (long)&site->key;
+}
 
 static inline struct static_call_key *static_call_key(const struct static_call_site *site)
 {
-	return (struct static_call_key *)
-		(((long)site->key + (long)&site->key) & ~STATIC_CALL_SITE_FLAGS);
+	return (void *)(__static_call_key(site) & ~STATIC_CALL_SITE_FLAGS);
 }
 
 /* These assume the key is word-aligned. */
 static inline bool static_call_is_init(struct static_call_site *site)
 {
-	return ((long)site->key + (long)&site->key) & STATIC_CALL_SITE_INIT;
+	return __static_call_key(site) & STATIC_CALL_SITE_INIT;
 }
 
 static inline bool static_call_is_tail(struct static_call_site *site)
 {
-	return ((long)site->key + (long)&site->key) & STATIC_CALL_SITE_TAIL;
+	return __static_call_key(site) & STATIC_CALL_SITE_TAIL;
 }
 
 static inline void static_call_set_init(struct static_call_site *site)
 {
-	site->key = ((long)static_call_key(site) | STATIC_CALL_SITE_INIT) -
+	site->key = (__static_call_key(site) | STATIC_CALL_SITE_INIT) -
 		    (long)&site->key;
 }
 
@@ -146,6 +149,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
 	};
 
 	for (site_mod = &first; site_mod; site_mod = site_mod->next) {
+		bool init = system_state < SYSTEM_RUNNING;
 		struct module *mod = site_mod->mod;
 
 		if (!site_mod->sites) {
@@ -165,6 +169,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
 		if (mod) {
 			stop = mod->static_call_sites +
 			       mod->num_static_call_sites;
+			init = mod->state == MODULE_STATE_COMING;
 		}
 #endif
 
@@ -172,25 +177,26 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
 		     site < stop && static_call_key(site) == key; site++) {
 			void *site_addr = static_call_addr(site);
 
-			if (static_call_is_init(site)) {
-				/*
-				 * Don't write to call sites which were in
-				 * initmem and have since been freed.
-				 */
-				if (!mod && system_state >= SYSTEM_RUNNING)
-					continue;
-				if (mod && !within_module_init((unsigned long)site_addr, mod))
-					continue;
-			}
+			if (!init && static_call_is_init(site))
+				continue;
 
 			if (!kernel_text_address((unsigned long)site_addr)) {
-				WARN_ONCE(1, "can't patch static call site at %pS",
+				/*
+				 * This skips patching built-in __exit, which
+				 * is part of init_section_contains() but is
+				 * not part of kernel_text_address().
+				 *
+				 * Skipping built-in __exit is fine since it
+				 * will never be executed.
+				 */
+				WARN_ONCE(!static_call_is_init(site),
+					  "can't patch static call site at %pS",
 					  site_addr);
 				continue;
 			}
 
 			arch_static_call_transform(site_addr, NULL, func,
-				static_call_is_tail(site));
+						   static_call_is_tail(site));
 		}
 	}
 
@@ -349,7 +355,8 @@ static int static_call_add_module(struct module *mod)
 	struct static_call_site *site;
 
 	for (site = start; site != stop; site++) {
-		unsigned long addr = (unsigned long)static_call_key(site);
+		unsigned long s_key = __static_call_key(site);
+		unsigned long addr = s_key & ~STATIC_CALL_SITE_FLAGS;
 		unsigned long key;
 
 		/*
@@ -373,8 +380,8 @@ static int static_call_add_module(struct module *mod)
 			return -EINVAL;
 		}
 
-		site->key = (key - (long)&site->key) |
-			    (site->key & STATIC_CALL_SITE_FLAGS);
+		key |= s_key & STATIC_CALL_SITE_FLAGS;
+		site->key = key - (long)&site->key;
 	}
 
 	return __static_call_init(mod, start, stop);
diff --git a/kernel/sys.c b/kernel/sys.c
index b09fe21e88ff..2e2e3f378d97 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2079,7 +2079,7 @@ static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr,
 	 * up to the caller to provide sane values here, otherwise userspace
 	 * tools which use this vector might be unhappy.
 	 */
-	unsigned long user_auxv[AT_VECTOR_SIZE];
+	unsigned long user_auxv[AT_VECTOR_SIZE] = {};
 
 	if (len > sizeof(user_auxv))
 		return -EINVAL;
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 98d7a15e8cf6..4d94e2b5499d 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -854,9 +854,9 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
 	if (flags == TIMER_ABSTIME)
 		return -ERESTARTNOHAND;
 
-	restart->fn = alarm_timer_nsleep_restart;
 	restart->nanosleep.clockid = type;
 	restart->nanosleep.expires = exp;
+	set_restart_fn(restart, alarm_timer_nsleep_restart);
 	return ret;
 }
 
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 743c852e10f2..5c9d968187ae 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -546,8 +546,11 @@ static ktime_t __hrtimer_next_event_base(struct hrtimer_cpu_base *cpu_base,
 }
 
 /*
- * Recomputes cpu_base::*next_timer and returns the earliest expires_next but
- * does not set cpu_base::*expires_next, that is done by hrtimer_reprogram.
+ * Recomputes cpu_base::*next_timer and returns the earliest expires_next
+ * but does not set cpu_base::*expires_next, that is done by
+ * hrtimer[_force]_reprogram and hrtimer_interrupt only. When updating
+ * cpu_base::*expires_next right away, reprogramming logic would no longer
+ * work.
  *
  * When a softirq is pending, we can ignore the HRTIMER_ACTIVE_SOFT bases,
  * those timers will get run whenever the softirq gets handled, at the end of
@@ -588,6 +591,37 @@ __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base, unsigned int active_
 	return expires_next;
 }
 
+static ktime_t hrtimer_update_next_event(struct hrtimer_cpu_base *cpu_base)
+{
+	ktime_t expires_next, soft = KTIME_MAX;
+
+	/*
+	 * If the soft interrupt has already been activated, ignore the
+	 * soft bases. They will be handled in the already raised soft
+	 * interrupt.
+	 */
+	if (!cpu_base->softirq_activated) {
+		soft = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_SOFT);
+		/*
+		 * Update the soft expiry time. clock_settime() might have
+		 * affected it.
+		 */
+		cpu_base->softirq_expires_next = soft;
+	}
+
+	expires_next = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_HARD);
+	/*
+	 * If a softirq timer is expiring first, update cpu_base->next_timer
+	 * and program the hardware with the soft expiry time.
+	 */
+	if (expires_next > soft) {
+		cpu_base->next_timer = cpu_base->softirq_next_timer;
+		expires_next = soft;
+	}
+
+	return expires_next;
+}
+
 static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
 {
 	ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset;
@@ -628,23 +662,7 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
 {
 	ktime_t expires_next;
 
-	/*
-	 * Find the current next expiration time.
-	 */
-	expires_next = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL);
-
-	if (cpu_base->next_timer && cpu_base->next_timer->is_soft) {
-		/*
-		 * When the softirq is activated, hrtimer has to be
-		 * programmed with the first hard hrtimer because soft
-		 * timer interrupt could occur too late.
-		 */
-		if (cpu_base->softirq_activated)
-			expires_next = __hrtimer_get_next_event(cpu_base,
-								HRTIMER_ACTIVE_HARD);
-		else
-			cpu_base->softirq_expires_next = expires_next;
-	}
+	expires_next = hrtimer_update_next_event(cpu_base);
 
 	if (skip_equal && expires_next == cpu_base->expires_next)
 		return;
@@ -1644,8 +1662,8 @@ retry:
 
 	__hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_HARD);
 
-	/* Reevaluate the clock bases for the next expiry */
-	expires_next = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL);
+	/* Reevaluate the clock bases for the [soft] next expiry */
+	expires_next = hrtimer_update_next_event(cpu_base);
 	/*
 	 * Store the new expiry value so the migration code can verify
 	 * against it.
@@ -1939,9 +1957,9 @@ long hrtimer_nanosleep(ktime_t rqtp, const enum hrtimer_mode mode,
 	}
 
 	restart = &current->restart_block;
-	restart->fn = hrtimer_nanosleep_restart;
 	restart->nanosleep.clockid = t.timer.base->clockid;
 	restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);
+	set_restart_fn(restart, hrtimer_nanosleep_restart);
 out:
 	destroy_hrtimer_on_stack(&t.timer);
 	return ret;
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index a71758e34e45..9abe15255bc4 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1480,8 +1480,8 @@ static int posix_cpu_nsleep(const clockid_t which_clock, int flags,
 		if (flags & TIMER_ABSTIME)
 			return -ERESTARTNOHAND;
 
-		restart_block->fn = posix_cpu_nsleep_restart;
 		restart_block->nanosleep.clockid = which_clock;
+		set_restart_fn(restart_block, posix_cpu_nsleep_restart);
 	}
 	return error;
 }
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4d8e35575549..b7e29db127fa 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -5045,6 +5045,20 @@ struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr)
 	return NULL;
 }
 
+static struct ftrace_direct_func *ftrace_alloc_direct_func(unsigned long addr)
+{
+	struct ftrace_direct_func *direct;
+
+	direct = kmalloc(sizeof(*direct), GFP_KERNEL);
+	if (!direct)
+		return NULL;
+	direct->addr = addr;
+	direct->count = 0;
+	list_add_rcu(&direct->next, &ftrace_direct_funcs);
+	ftrace_direct_func_count++;
+	return direct;
+}
+
 /**
  * register_ftrace_direct - Call a custom trampoline directly
  * @ip: The address of the nop at the beginning of a function
@@ -5120,15 +5134,11 @@ int register_ftrace_direct(unsigned long ip, unsigned long addr)
 
 	direct = ftrace_find_direct_func(addr);
 	if (!direct) {
-		direct = kmalloc(sizeof(*direct), GFP_KERNEL);
+		direct = ftrace_alloc_direct_func(addr);
 		if (!direct) {
 			kfree(entry);
 			goto out_unlock;
 		}
-		direct->addr = addr;
-		direct->count = 0;
-		list_add_rcu(&direct->next, &ftrace_direct_funcs);
-		ftrace_direct_func_count++;
 	}
 
 	entry->ip = ip;
@@ -5329,6 +5339,7 @@ int __weak ftrace_modify_direct_caller(struct ftrace_func_entry *entry,
 int modify_ftrace_direct(unsigned long ip,
 			 unsigned long old_addr, unsigned long new_addr)
 {
+	struct ftrace_direct_func *direct, *new_direct = NULL;
 	struct ftrace_func_entry *entry;
 	struct dyn_ftrace *rec;
 	int ret = -ENODEV;
@@ -5344,6 +5355,20 @@ int modify_ftrace_direct(unsigned long ip,
 	if (entry->direct != old_addr)
 		goto out_unlock;
 
+	direct = ftrace_find_direct_func(old_addr);
+	if (WARN_ON(!direct))
+		goto out_unlock;
+	if (direct->count > 1) {
+		ret = -ENOMEM;
+		new_direct = ftrace_alloc_direct_func(new_addr);
+		if (!new_direct)
+			goto out_unlock;
+		direct->count--;
+		new_direct->count++;
+	} else {
+		direct->addr = new_addr;
+	}
+
 	/*
 	 * If there's no other ftrace callback on the rec->ip location,
 	 * then it can be changed directly by the architecture.
@@ -5357,6 +5382,14 @@ int modify_ftrace_direct(unsigned long ip,
 		ret = 0;
 	}
 
+	if (unlikely(ret && new_direct)) {
+		direct->count++;
+		list_del_rcu(&new_direct->next);
+		synchronize_rcu_tasks();
+		kfree(new_direct);
+		ftrace_direct_func_count--;
+	}
+
  out_unlock:
 	mutex_unlock(&ftrace_lock);
 	mutex_unlock(&direct_mutex);
diff --git a/kernel/usermode_driver.c b/kernel/usermode_driver.c
index 0b35212ffc3d..bb7bb3b478ab 100644
--- a/kernel/usermode_driver.c
+++ b/kernel/usermode_driver.c
@@ -139,13 +139,22 @@ static void umd_cleanup(struct subprocess_info *info)
 	struct umd_info *umd_info = info->data;
 
 	/* cleanup if umh_setup() was successful but exec failed */
-	if (info->retval) {
-		fput(umd_info->pipe_to_umh);
-		fput(umd_info->pipe_from_umh);
-		put_pid(umd_info->tgid);
-		umd_info->tgid = NULL;
-	}
+	if (info->retval)
+		umd_cleanup_helper(umd_info);
+}
+
+/**
+ * umd_cleanup_helper - release the resources which were allocated in umd_setup
+ * @info: information about usermode driver
+ */
+void umd_cleanup_helper(struct umd_info *info)
+{
+	fput(info->pipe_to_umh);
+	fput(info->pipe_from_umh);
+	put_pid(info->tgid);
+	info->tgid = NULL;
 }
+EXPORT_SYMBOL_GPL(umd_cleanup_helper);
 
 /**
  * fork_usermode_driver - fork a usermode driver