Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:

 - most of the rest of MM

 - a small number of misc things

 - lib/ updates

 - checkpatch

 - autofs updates

 - ipc/ updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (126 commits)
  ipc: optimize semget/shmget/msgget for lots of keys
  ipc/sem: play nicer with large nsops allocations
  ipc/sem: drop sem_checkid helper
  ipc: convert kern_ipc_perm.refcount from atomic_t to refcount_t
  ipc: convert sem_undo_list.refcnt from atomic_t to refcount_t
  ipc: convert ipc_namespace.count from atomic_t to refcount_t
  kcov: support compat processes
  sh: defconfig: cleanup from old Kconfig options
  mn10300: defconfig: cleanup from old Kconfig options
  m32r: defconfig: cleanup from old Kconfig options
  drivers/pps: use surrounding "if PPS" to remove numerous dependency checks
  drivers/pps: aesthetic tweaks to PPS-related content
  cpumask: make cpumask_next() out-of-line
  kmod: move #ifdef CONFIG_MODULES wrapper to Makefile
  kmod: split off umh headers into its own file
  MAINTAINERS: clarify kmod is just a kernel module loader
  kmod: split out umh code into its own file
  test_kmod: flip INT checks to be consistent
  test_kmod: remove paranoid UINT_MAX check on uint range processing
  vfat: deduplicate hex2bin()
  ...

19 files changed, 696 insertions, 666 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 9c323a6..ed470aa 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -5,12 +5,13 @@
 obj-y     = fork.o exec_domain.o panic.o \
 	    cpu.o exit.o softirq.o resource.o \
 	    sysctl.o sysctl_binary.o capability.o ptrace.o user.o \
-	    signal.o sys.o kmod.o workqueue.o pid.o task_work.o \
+	    signal.o sys.o umh.o workqueue.o pid.o task_work.o \
 	    extable.o params.o \
 	    kthread.o sys_ni.o nsproxy.o \
 	    notifier.o ksysfs.o cred.o reboot.o \
 	    async.o range.o smpboot.o ucount.o
 
+obj-$(CONFIG_MODULES) += kmod.o
 obj-$(CONFIG_MULTIUSER) += groups.o
 
 ifdef CONFIG_FUNCTION_TRACER
diff --git a/kernel/fork.c b/kernel/fork.c
index 24a4c0b..6f1b0af 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -37,6 +37,7 @@
 #include <linux/binfmts.h>
 #include <linux/mman.h>
 #include <linux/mmu_notifier.h>
+#include <linux/hmm.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/vmacache.h>
@@ -824,6 +825,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 	mm_init_owner(mm, p);
 	RCU_INIT_POINTER(mm->exe_file, NULL);
 	mmu_notifier_mm_init(mm);
+	hmm_mm_init(mm);
 	init_tlb_flush_pending(mm);
 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS
 	mm->pmd_huge_pte = NULL;
@@ -903,6 +905,7 @@ void __mmdrop(struct mm_struct *mm)
 	BUG_ON(mm == &init_mm);
 	mm_free_pgd(mm);
 	destroy_context(mm);
+	hmm_mm_destroy(mm);
 	mmu_notifier_mm_destroy(mm);
 	check_mm(mm);
 	put_user_ns(mm->user_ns);
@@ -1459,8 +1462,7 @@ static void rt_mutex_init_task(struct task_struct *p)
 {
 	raw_spin_lock_init(&p->pi_lock);
 #ifdef CONFIG_RT_MUTEXES
-	p->pi_waiters = RB_ROOT;
-	p->pi_waiters_leftmost = NULL;
+	p->pi_waiters = RB_ROOT_CACHED;
 	p->pi_top_task = NULL;
 	p->pi_blocked_on = NULL;
 #endif
diff --git a/kernel/kcov.c b/kernel/kcov.c
index cd77199..3f693a0 100644
--- a/kernel/kcov.c
+++ b/kernel/kcov.c
@@ -270,6 +270,7 @@ static long kcov_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 static const struct file_operations kcov_fops = {
 	.open		= kcov_open,
 	.unlocked_ioctl	= kcov_ioctl,
+	.compat_ioctl	= kcov_ioctl,
 	.mmap		= kcov_mmap,
 	.release        = kcov_close,
 };
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 2f37acd..bc6addd 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -1,23 +1,6 @@
 /*
-	kmod, the new module loader (replaces kerneld)
-	Kirk Petersen
-
-	Reorganized not to be a daemon by Adam Richter, with guidance
-	from Greg Zornetzer.
-
-	Modified to avoid chroot and file sharing problems.
-	Mikael Pettersson
-
-	Limit the concurrent number of kmod modprobes to catch loops from
-	"modprobe needs a service that is in a module".
-	Keith Owens <kaos@ocs.com.au> December 1999
-
-	Unblock all signals when we exec a usermode process.
-	Shuu Yamaguchi <shuu@wondernetworkresources.com> December 2000
-
-	call_usermodehelper wait flag, and remove exec_usermodehelper.
-	Rusty Russell <rusty@rustcorp.com.au>  Jan 2003
-*/
+ * kmod - the kernel module loader
+ */
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/sched/task.h>
@@ -45,15 +28,6 @@
 
 #include <trace/events/module.h>
 
-#define CAP_BSET	(void *)1
-#define CAP_PI		(void *)2
-
-static kernel_cap_t usermodehelper_bset = CAP_FULL_SET;
-static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET;
-static DEFINE_SPINLOCK(umh_sysctl_lock);
-static DECLARE_RWSEM(umhelper_sem);
-
-#ifdef CONFIG_MODULES
 /*
  * Assuming:
  *
@@ -202,536 +176,3 @@ int __request_module(bool wait, const char *fmt, ...)
 	return ret;
 }
 EXPORT_SYMBOL(__request_module);
-
-#endif /* CONFIG_MODULES */
-
-static void call_usermodehelper_freeinfo(struct subprocess_info *info)
-{
-	if (info->cleanup)
-		(*info->cleanup)(info);
-	kfree(info);
-}
-
-static void umh_complete(struct subprocess_info *sub_info)
-{
-	struct completion *comp = xchg(&sub_info->complete, NULL);
-	/*
-	 * See call_usermodehelper_exec(). If xchg() returns NULL
-	 * we own sub_info, the UMH_KILLABLE caller has gone away
-	 * or the caller used UMH_NO_WAIT.
-	 */
-	if (comp)
-		complete(comp);
-	else
-		call_usermodehelper_freeinfo(sub_info);
-}
-
-/*
- * This is the task which runs the usermode application
- */
-static int call_usermodehelper_exec_async(void *data)
-{
-	struct subprocess_info *sub_info = data;
-	struct cred *new;
-	int retval;
-
-	spin_lock_irq(&current->sighand->siglock);
-	flush_signal_handlers(current, 1);
-	spin_unlock_irq(&current->sighand->siglock);
-
-	/*
-	 * Our parent (unbound workqueue) runs with elevated scheduling
-	 * priority. Avoid propagating that into the userspace child.
-	 */
-	set_user_nice(current, 0);
-
-	retval = -ENOMEM;
-	new = prepare_kernel_cred(current);
-	if (!new)
-		goto out;
-
-	spin_lock(&umh_sysctl_lock);
-	new->cap_bset = cap_intersect(usermodehelper_bset, new->cap_bset);
-	new->cap_inheritable = cap_intersect(usermodehelper_inheritable,
-					     new->cap_inheritable);
-	spin_unlock(&umh_sysctl_lock);
-
-	if (sub_info->init) {
-		retval = sub_info->init(sub_info, new);
-		if (retval) {
-			abort_creds(new);
-			goto out;
-		}
-	}
-
-	commit_creds(new);
-
-	retval = do_execve(getname_kernel(sub_info->path),
-			   (const char __user *const __user *)sub_info->argv,
-			   (const char __user *const __user *)sub_info->envp);
-out:
-	sub_info->retval = retval;
-	/*
-	 * call_usermodehelper_exec_sync() will call umh_complete
-	 * if UHM_WAIT_PROC.
-	 */
-	if (!(sub_info->wait & UMH_WAIT_PROC))
-		umh_complete(sub_info);
-	if (!retval)
-		return 0;
-	do_exit(0);
-}
-
-/* Handles UMH_WAIT_PROC.  */
-static void call_usermodehelper_exec_sync(struct subprocess_info *sub_info)
-{
-	pid_t pid;
-
-	/* If SIGCLD is ignored sys_wait4 won't populate the status. */
-	kernel_sigaction(SIGCHLD, SIG_DFL);
-	pid = kernel_thread(call_usermodehelper_exec_async, sub_info, SIGCHLD);
-	if (pid < 0) {
-		sub_info->retval = pid;
-	} else {
-		int ret = -ECHILD;
-		/*
-		 * Normally it is bogus to call wait4() from in-kernel because
-		 * wait4() wants to write the exit code to a userspace address.
-		 * But call_usermodehelper_exec_sync() always runs as kernel
-		 * thread (workqueue) and put_user() to a kernel address works
-		 * OK for kernel threads, due to their having an mm_segment_t
-		 * which spans the entire address space.
-		 *
-		 * Thus the __user pointer cast is valid here.
-		 */
-		sys_wait4(pid, (int __user *)&ret, 0, NULL);
-
-		/*
-		 * If ret is 0, either call_usermodehelper_exec_async failed and
-		 * the real error code is already in sub_info->retval or
-		 * sub_info->retval is 0 anyway, so don't mess with it then.
-		 */
-		if (ret)
-			sub_info->retval = ret;
-	}
-
-	/* Restore default kernel sig handler */
-	kernel_sigaction(SIGCHLD, SIG_IGN);
-
-	umh_complete(sub_info);
-}
-
-/*
- * We need to create the usermodehelper kernel thread from a task that is affine
- * to an optimized set of CPUs (or nohz housekeeping ones) such that they
- * inherit a widest affinity irrespective of call_usermodehelper() callers with
- * possibly reduced affinity (eg: per-cpu workqueues). We don't want
- * usermodehelper targets to contend a busy CPU.
- *
- * Unbound workqueues provide such wide affinity and allow to block on
- * UMH_WAIT_PROC requests without blocking pending request (up to some limit).
- *
- * Besides, workqueues provide the privilege level that caller might not have
- * to perform the usermodehelper request.
- *
- */
-static void call_usermodehelper_exec_work(struct work_struct *work)
-{
-	struct subprocess_info *sub_info =
-		container_of(work, struct subprocess_info, work);
-
-	if (sub_info->wait & UMH_WAIT_PROC) {
-		call_usermodehelper_exec_sync(sub_info);
-	} else {
-		pid_t pid;
-		/*
-		 * Use CLONE_PARENT to reparent it to kthreadd; we do not
-		 * want to pollute current->children, and we need a parent
-		 * that always ignores SIGCHLD to ensure auto-reaping.
-		 */
-		pid = kernel_thread(call_usermodehelper_exec_async, sub_info,
-				    CLONE_PARENT | SIGCHLD);
-		if (pid < 0) {
-			sub_info->retval = pid;
-			umh_complete(sub_info);
-		}
-	}
-}
-
-/*
- * If set, call_usermodehelper_exec() will exit immediately returning -EBUSY
- * (used for preventing user land processes from being created after the user
- * land has been frozen during a system-wide hibernation or suspend operation).
- * Should always be manipulated under umhelper_sem acquired for write.
- */
-static enum umh_disable_depth usermodehelper_disabled = UMH_DISABLED;
-
-/* Number of helpers running */
-static atomic_t running_helpers = ATOMIC_INIT(0);
-
-/*
- * Wait queue head used by usermodehelper_disable() to wait for all running
- * helpers to finish.
- */
-static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq);
-
-/*
- * Used by usermodehelper_read_lock_wait() to wait for usermodehelper_disabled
- * to become 'false'.
- */
-static DECLARE_WAIT_QUEUE_HEAD(usermodehelper_disabled_waitq);
-
-/*
- * Time to wait for running_helpers to become zero before the setting of
- * usermodehelper_disabled in usermodehelper_disable() fails
- */
-#define RUNNING_HELPERS_TIMEOUT	(5 * HZ)
-
-int usermodehelper_read_trylock(void)
-{
-	DEFINE_WAIT(wait);
-	int ret = 0;
-
-	down_read(&umhelper_sem);
-	for (;;) {
-		prepare_to_wait(&usermodehelper_disabled_waitq, &wait,
-				TASK_INTERRUPTIBLE);
-		if (!usermodehelper_disabled)
-			break;
-
-		if (usermodehelper_disabled == UMH_DISABLED)
-			ret = -EAGAIN;
-
-		up_read(&umhelper_sem);
-
-		if (ret)
-			break;
-
-		schedule();
-		try_to_freeze();
-
-		down_read(&umhelper_sem);
-	}
-	finish_wait(&usermodehelper_disabled_waitq, &wait);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(usermodehelper_read_trylock);
-
-long usermodehelper_read_lock_wait(long timeout)
-{
-	DEFINE_WAIT(wait);
-
-	if (timeout < 0)
-		return -EINVAL;
-
-	down_read(&umhelper_sem);
-	for (;;) {
-		prepare_to_wait(&usermodehelper_disabled_waitq, &wait,
-				TASK_UNINTERRUPTIBLE);
-		if (!usermodehelper_disabled)
-			break;
-
-		up_read(&umhelper_sem);
-
-		timeout = schedule_timeout(timeout);
-		if (!timeout)
-			break;
-
-		down_read(&umhelper_sem);
-	}
-	finish_wait(&usermodehelper_disabled_waitq, &wait);
-	return timeout;
-}
-EXPORT_SYMBOL_GPL(usermodehelper_read_lock_wait);
-
-void usermodehelper_read_unlock(void)
-{
-	up_read(&umhelper_sem);
-}
-EXPORT_SYMBOL_GPL(usermodehelper_read_unlock);
-
-/**
- * __usermodehelper_set_disable_depth - Modify usermodehelper_disabled.
- * @depth: New value to assign to usermodehelper_disabled.
- *
- * Change the value of usermodehelper_disabled (under umhelper_sem locked for
- * writing) and wakeup tasks waiting for it to change.
- */
-void __usermodehelper_set_disable_depth(enum umh_disable_depth depth)
-{
-	down_write(&umhelper_sem);
-	usermodehelper_disabled = depth;
-	wake_up(&usermodehelper_disabled_waitq);
-	up_write(&umhelper_sem);
-}
-
-/**
- * __usermodehelper_disable - Prevent new helpers from being started.
- * @depth: New value to assign to usermodehelper_disabled.
- *
- * Set usermodehelper_disabled to @depth and wait for running helpers to exit.
- */
-int __usermodehelper_disable(enum umh_disable_depth depth)
-{
-	long retval;
-
-	if (!depth)
-		return -EINVAL;
-
-	down_write(&umhelper_sem);
-	usermodehelper_disabled = depth;
-	up_write(&umhelper_sem);
-
-	/*
-	 * From now on call_usermodehelper_exec() won't start any new
-	 * helpers, so it is sufficient if running_helpers turns out to
-	 * be zero at one point (it may be increased later, but that
-	 * doesn't matter).
-	 */
-	retval = wait_event_timeout(running_helpers_waitq,
-					atomic_read(&running_helpers) == 0,
-					RUNNING_HELPERS_TIMEOUT);
-	if (retval)
-		return 0;
-
-	__usermodehelper_set_disable_depth(UMH_ENABLED);
-	return -EAGAIN;
-}
-
-static void helper_lock(void)
-{
-	atomic_inc(&running_helpers);
-	smp_mb__after_atomic();
-}
-
-static void helper_unlock(void)
-{
-	if (atomic_dec_and_test(&running_helpers))
-		wake_up(&running_helpers_waitq);
-}
-
-/**
- * call_usermodehelper_setup - prepare to call a usermode helper
- * @path: path to usermode executable
- * @argv: arg vector for process
- * @envp: environment for process
- * @gfp_mask: gfp mask for memory allocation
- * @cleanup: a cleanup function
- * @init: an init function
- * @data: arbitrary context sensitive data
- *
- * Returns either %NULL on allocation failure, or a subprocess_info
- * structure.  This should be passed to call_usermodehelper_exec to
- * exec the process and free the structure.
- *
- * The init function is used to customize the helper process prior to
- * exec.  A non-zero return code causes the process to error out, exit,
- * and return the failure to the calling process
- *
- * The cleanup function is just before ethe subprocess_info is about to
- * be freed.  This can be used for freeing the argv and envp.  The
- * Function must be runnable in either a process context or the
- * context in which call_usermodehelper_exec is called.
- */
-struct subprocess_info *call_usermodehelper_setup(const char *path, char **argv,
-		char **envp, gfp_t gfp_mask,
-		int (*init)(struct subprocess_info *info, struct cred *new),
-		void (*cleanup)(struct subprocess_info *info),
-		void *data)
-{
-	struct subprocess_info *sub_info;
-	sub_info = kzalloc(sizeof(struct subprocess_info), gfp_mask);
-	if (!sub_info)
-		goto out;
-
-	INIT_WORK(&sub_info->work, call_usermodehelper_exec_work);
-
-#ifdef CONFIG_STATIC_USERMODEHELPER
-	sub_info->path = CONFIG_STATIC_USERMODEHELPER_PATH;
-#else
-	sub_info->path = path;
-#endif
-	sub_info->argv = argv;
-	sub_info->envp = envp;
-
-	sub_info->cleanup = cleanup;
-	sub_info->init = init;
-	sub_info->data = data;
-  out:
-	return sub_info;
-}
-EXPORT_SYMBOL(call_usermodehelper_setup);
-
-/**
- * call_usermodehelper_exec - start a usermode application
- * @sub_info: information about the subprocessa
- * @wait: wait for the application to finish and return status.
- *        when UMH_NO_WAIT don't wait at all, but you get no useful error back
- *        when the program couldn't be exec'ed. This makes it safe to call
- *        from interrupt context.
- *
- * Runs a user-space application.  The application is started
- * asynchronously if wait is not set, and runs as a child of system workqueues.
- * (ie. it runs with full root capabilities and optimized affinity).
- */
-int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
-{
-	DECLARE_COMPLETION_ONSTACK(done);
-	int retval = 0;
-
-	if (!sub_info->path) {
-		call_usermodehelper_freeinfo(sub_info);
-		return -EINVAL;
-	}
-	helper_lock();
-	if (usermodehelper_disabled) {
-		retval = -EBUSY;
-		goto out;
-	}
-
-	/*
-	 * If there is no binary for us to call, then just return and get out of
-	 * here.  This allows us to set STATIC_USERMODEHELPER_PATH to "" and
-	 * disable all call_usermodehelper() calls.
-	 */
-	if (strlen(sub_info->path) == 0)
-		goto out;
-
-	/*
-	 * Set the completion pointer only if there is a waiter.
-	 * This makes it possible to use umh_complete to free
-	 * the data structure in case of UMH_NO_WAIT.
-	 */
-	sub_info->complete = (wait == UMH_NO_WAIT) ? NULL : &done;
-	sub_info->wait = wait;
-
-	queue_work(system_unbound_wq, &sub_info->work);
-	if (wait == UMH_NO_WAIT)	/* task has freed sub_info */
-		goto unlock;
-
-	if (wait & UMH_KILLABLE) {
-		retval = wait_for_completion_killable(&done);
-		if (!retval)
-			goto wait_done;
-
-		/* umh_complete() will see NULL and free sub_info */
-		if (xchg(&sub_info->complete, NULL))
-			goto unlock;
-		/* fallthrough, umh_complete() was already called */
-	}
-
-	wait_for_completion(&done);
-wait_done:
-	retval = sub_info->retval;
-out:
-	call_usermodehelper_freeinfo(sub_info);
-unlock:
-	helper_unlock();
-	return retval;
-}
-EXPORT_SYMBOL(call_usermodehelper_exec);
-
-/**
- * call_usermodehelper() - prepare and start a usermode application
- * @path: path to usermode executable
- * @argv: arg vector for process
- * @envp: environment for process
- * @wait: wait for the application to finish and return status.
- *        when UMH_NO_WAIT don't wait at all, but you get no useful error back
- *        when the program couldn't be exec'ed. This makes it safe to call
- *        from interrupt context.
- *
- * This function is the equivalent to use call_usermodehelper_setup() and
- * call_usermodehelper_exec().
- */
-int call_usermodehelper(const char *path, char **argv, char **envp, int wait)
-{
-	struct subprocess_info *info;
-	gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
-
-	info = call_usermodehelper_setup(path, argv, envp, gfp_mask,
-					 NULL, NULL, NULL);
-	if (info == NULL)
-		return -ENOMEM;
-
-	return call_usermodehelper_exec(info, wait);
-}
-EXPORT_SYMBOL(call_usermodehelper);
-
-static int proc_cap_handler(struct ctl_table *table, int write,
-			 void __user *buffer, size_t *lenp, loff_t *ppos)
-{
-	struct ctl_table t;
-	unsigned long cap_array[_KERNEL_CAPABILITY_U32S];
-	kernel_cap_t new_cap;
-	int err, i;
-
-	if (write && (!capable(CAP_SETPCAP) ||
-		      !capable(CAP_SYS_MODULE)))
-		return -EPERM;
-
-	/*
-	 * convert from the global kernel_cap_t to the ulong array to print to
-	 * userspace if this is a read.
-	 */
-	spin_lock(&umh_sysctl_lock);
-	for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++)  {
-		if (table->data == CAP_BSET)
-			cap_array[i] = usermodehelper_bset.cap[i];
-		else if (table->data == CAP_PI)
-			cap_array[i] = usermodehelper_inheritable.cap[i];
-		else
-			BUG();
-	}
-	spin_unlock(&umh_sysctl_lock);
-
-	t = *table;
-	t.data = &cap_array;
-
-	/*
-	 * actually read or write and array of ulongs from userspace.  Remember
-	 * these are least significant 32 bits first
-	 */
-	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
-	if (err < 0)
-		return err;
-
-	/*
-	 * convert from the sysctl array of ulongs to the kernel_cap_t
-	 * internal representation
-	 */
-	for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++)
-		new_cap.cap[i] = cap_array[i];
-
-	/*
-	 * Drop everything not in the new_cap (but don't add things)
-	 */
-	spin_lock(&umh_sysctl_lock);
-	if (write) {
-		if (table->data == CAP_BSET)
-			usermodehelper_bset = cap_intersect(usermodehelper_bset, new_cap);
-		if (table->data == CAP_PI)
-			usermodehelper_inheritable = cap_intersect(usermodehelper_inheritable, new_cap);
-	}
-	spin_unlock(&umh_sysctl_lock);
-
-	return 0;
-}
-
-struct ctl_table usermodehelper_table[] = {
-	{
-		.procname	= "bset",
-		.data		= CAP_BSET,
-		.maxlen		= _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
-		.mode		= 0600,
-		.proc_handler	= proc_cap_handler,
-	},
-	{
-		.procname	= "inheritable",
-		.data		= CAP_PI,
-		.maxlen		= _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
-		.mode		= 0600,
-		.proc_handler	= proc_cap_handler,
-	},
-	{ }
-};
diff --git a/kernel/locking/rtmutex-debug.c b/kernel/locking/rtmutex-debug.c
index ac35e64..f4a74e7 100644
--- a/kernel/locking/rtmutex-debug.c
+++ b/kernel/locking/rtmutex-debug.c
@@ -58,7 +58,7 @@ static void printk_lock(struct rt_mutex *lock, int print_owner)
 
 void rt_mutex_debug_task_free(struct task_struct *task)
 {
-	DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters));
+	DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters.rb_root));
 	DEBUG_LOCKS_WARN_ON(task->pi_blocked_on);
 }
 
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 649dc9d..6f3dba6 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -271,10 +271,10 @@ rt_mutex_waiter_equal(struct rt_mutex_waiter *left,
 static void
 rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
 {
-	struct rb_node **link = &lock->waiters.rb_node;
+	struct rb_node **link = &lock->waiters.rb_root.rb_node;
 	struct rb_node *parent = NULL;
 	struct rt_mutex_waiter *entry;
-	int leftmost = 1;
+	bool leftmost = true;
 
 	while (*link) {
 		parent = *link;
@@ -283,15 +283,12 @@ rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
 			link = &parent->rb_left;
 		} else {
 			link = &parent->rb_right;
-			leftmost = 0;
+			leftmost = false;
 		}
 	}
 
-	if (leftmost)
-		lock->waiters_leftmost = &waiter->tree_entry;
-
 	rb_link_node(&waiter->tree_entry, parent, link);
-	rb_insert_color(&waiter->tree_entry, &lock->waiters);
+	rb_insert_color_cached(&waiter->tree_entry, &lock->waiters, leftmost);
 }
 
 static void
@@ -300,20 +297,17 @@ rt_mutex_dequeue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
 	if (RB_EMPTY_NODE(&waiter->tree_entry))
 		return;
 
-	if (lock->waiters_leftmost == &waiter->tree_entry)
-		lock->waiters_leftmost = rb_next(&waiter->tree_entry);
-
-	rb_erase(&waiter->tree_entry, &lock->waiters);
+	rb_erase_cached(&waiter->tree_entry, &lock->waiters);
 	RB_CLEAR_NODE(&waiter->tree_entry);
 }
 
 static void
 rt_mutex_enqueue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter)
 {
-	struct rb_node **link = &task->pi_waiters.rb_node;
+	struct rb_node **link = &task->pi_waiters.rb_root.rb_node;
 	struct rb_node *parent = NULL;
 	struct rt_mutex_waiter *entry;
-	int leftmost = 1;
+	bool leftmost = true;
 
 	while (*link) {
 		parent = *link;
@@ -322,15 +316,12 @@ rt_mutex_enqueue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter)
 			link = &parent->rb_left;
 		} else {
 			link = &parent->rb_right;
-			leftmost = 0;
+			leftmost = false;
 		}
 	}
 
-	if (leftmost)
-		task->pi_waiters_leftmost = &waiter->pi_tree_entry;
-
 	rb_link_node(&waiter->pi_tree_entry, parent, link);
-	rb_insert_color(&waiter->pi_tree_entry, &task->pi_waiters);
+	rb_insert_color_cached(&waiter->pi_tree_entry, &task->pi_waiters, leftmost);
 }
 
 static void
@@ -339,10 +330,7 @@ rt_mutex_dequeue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter)
 	if (RB_EMPTY_NODE(&waiter->pi_tree_entry))
 		return;
 
-	if (task->pi_waiters_leftmost == &waiter->pi_tree_entry)
-		task->pi_waiters_leftmost = rb_next(&waiter->pi_tree_entry);
-
-	rb_erase(&waiter->pi_tree_entry, &task->pi_waiters);
+	rb_erase_cached(&waiter->pi_tree_entry, &task->pi_waiters);
 	RB_CLEAR_NODE(&waiter->pi_tree_entry);
 }
 
@@ -1657,8 +1645,7 @@ void __rt_mutex_init(struct rt_mutex *lock, const char *name,
 {
 	lock->owner = NULL;
 	raw_spin_lock_init(&lock->wait_lock);
-	lock->waiters = RB_ROOT;
-	lock->waiters_leftmost = NULL;
+	lock->waiters = RB_ROOT_CACHED;
 
 	if (name && key)
 		debug_rt_mutex_init(lock, name, key);
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index 8d039b9..7453be0 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -45,7 +45,7 @@ struct rt_mutex_waiter {
 
 static inline int rt_mutex_has_waiters(struct rt_mutex *lock)
 {
-	return !RB_EMPTY_ROOT(&lock->waiters);
+	return !RB_EMPTY_ROOT(&lock->waiters.rb_root);
 }
 
 static inline struct rt_mutex_waiter *
@@ -53,8 +53,8 @@ rt_mutex_top_waiter(struct rt_mutex *lock)
 {
 	struct rt_mutex_waiter *w;
 
-	w = rb_entry(lock->waiters_leftmost, struct rt_mutex_waiter,
-		     tree_entry);
+	w = rb_entry(lock->waiters.rb_leftmost,
+		     struct rt_mutex_waiter, tree_entry);
 	BUG_ON(w->lock != lock);
 
 	return w;
@@ -62,14 +62,14 @@ rt_mutex_top_waiter(struct rt_mutex *lock)
 
 static inline int task_has_pi_waiters(struct task_struct *p)
 {
-	return !RB_EMPTY_ROOT(&p->pi_waiters);
+	return !RB_EMPTY_ROOT(&p->pi_waiters.rb_root);
 }
 
 static inline struct rt_mutex_waiter *
 task_top_pi_waiter(struct task_struct *p)
 {
-	return rb_entry(p->pi_waiters_leftmost, struct rt_mutex_waiter,
-			pi_tree_entry);
+	return rb_entry(p->pi_waiters.rb_leftmost,
+			struct rt_mutex_waiter, pi_tree_entry);
 }
 
 #else
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 066e73c..6bcbfbf 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -11,13 +11,14 @@
  * General Public License for more details.
  */
 #include <linux/radix-tree.h>
-#include <linux/memremap.h>
 #include <linux/device.h>
 #include <linux/types.h>
 #include <linux/pfn_t.h>
 #include <linux/io.h>
 #include <linux/mm.h>
 #include <linux/memory_hotplug.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
 
 #ifndef ioremap_cache
 /* temporary while we convert existing ioremap_cache users to memremap */
@@ -219,6 +220,34 @@ static unsigned long order_at(struct resource *res, unsigned long pgoff)
 	for (pgoff = 0, order = order_at((res), pgoff); order < ULONG_MAX; \
 			pgoff += 1UL << order, order = order_at((res), pgoff))
 
+#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)
+int device_private_entry_fault(struct vm_area_struct *vma,
+		       unsigned long addr,
+		       swp_entry_t entry,
+		       unsigned int flags,
+		       pmd_t *pmdp)
+{
+	struct page *page = device_private_entry_to_page(entry);
+
+	/*
+	 * The page_fault() callback must migrate page back to system memory
+	 * so that CPU can access it. This might fail for various reasons
+	 * (device issue, device was unsafely unplugged, ...). When such
+	 * error conditions happen, the callback must return VM_FAULT_SIGBUS.
+	 *
+	 * Note that because memory cgroup charges are accounted to the device
+	 * memory, this should never fail because of memory restrictions (but
+	 * allocation of regular system page might still fail because we are
+	 * out of memory).
+	 *
+	 * There is a more in-depth description of what that callback can and
+	 * cannot do, in include/linux/memremap.h
+	 */
+	return page->pgmap->page_fault(vma, addr, page, flags, pmdp);
+}
+EXPORT_SYMBOL(device_private_entry_fault);
+#endif /* CONFIG_DEVICE_PRIVATE */
+
 static void pgmap_radix_release(struct resource *res)
 {
 	unsigned long pgoff, order;
@@ -356,6 +385,10 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 	}
 	pgmap->ref = ref;
 	pgmap->res = &page_map->res;
+	pgmap->type = MEMORY_DEVICE_HOST;
+	pgmap->page_fault = NULL;
+	pgmap->page_free = NULL;
+	pgmap->data = NULL;
 
 	mutex_lock(&pgmap_lock);
 	error = 0;
@@ -466,3 +499,28 @@ struct vmem_altmap *to_vmem_altmap(unsigned long memmap_start)
 	return pgmap ? pgmap->altmap : NULL;
 }
 #endif /* CONFIG_ZONE_DEVICE */
+
+
+#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) ||  IS_ENABLED(CONFIG_DEVICE_PUBLIC)
+void put_zone_device_private_or_public_page(struct page *page)
+{
+	int count = page_ref_dec_return(page);
+
+	/*
+	 * If refcount is 1 then page is freed and refcount is stable as nobody
+	 * holds a reference on the page.
+	 */
+	if (count == 1) {
+		/* Clear Active bit in case of parallel mark_page_accessed */
+		__ClearPageActive(page);
+		__ClearPageWaiters(page);
+
+		page->mapping = NULL;
+		mem_cgroup_uncharge(page);
+
+		page->pgmap->page_free(page, page->pgmap->data);
+	} else if (!count)
+		__put_page(page);
+}
+EXPORT_SYMBOL(put_zone_device_private_or_public_page);
+#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 84fe966..1250e4b 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -4091,7 +4091,7 @@ static void __init rcu_init_geometry(void)
 	if (rcu_fanout_leaf == RCU_FANOUT_LEAF &&
 	    nr_cpu_ids == NR_CPUS)
 		return;
-	pr_info("RCU: Adjusting geometry for rcu_fanout_leaf=%d, nr_cpu_ids=%d\n",
+	pr_info("RCU: Adjusting geometry for rcu_fanout_leaf=%d, nr_cpu_ids=%u\n",
 		rcu_fanout_leaf, nr_cpu_ids);
 
 	/*
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 55bde94..e012b9b 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -89,7 +89,7 @@ static void __init rcu_bootup_announce_oddness(void)
 	if (rcu_fanout_leaf != RCU_FANOUT_LEAF)
 		pr_info("\tBoot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf);
 	if (nr_cpu_ids != NR_CPUS)
-		pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%d.\n", NR_CPUS, nr_cpu_ids);
+		pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%u.\n", NR_CPUS, nr_cpu_ids);
 #ifdef CONFIG_RCU_BOOST
 	pr_info("\tRCU priority boosting: priority %d delay %d ms.\n", kthread_prio, CONFIG_RCU_BOOST_DELAY);
 #endif
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 9e38df7..0191ec7 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -296,7 +296,7 @@ static inline int is_leftmost(struct task_struct *p, struct dl_rq *dl_rq)
 {
 	struct sched_dl_entity *dl_se = &p->dl;
 
-	return dl_rq->rb_leftmost == &dl_se->rb_node;
+	return dl_rq->root.rb_leftmost == &dl_se->rb_node;
 }
 
 void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime)
@@ -320,7 +320,7 @@ void init_dl_bw(struct dl_bw *dl_b)
 
 void init_dl_rq(struct dl_rq *dl_rq)
 {
-	dl_rq->rb_root = RB_ROOT;
+	dl_rq->root = RB_ROOT_CACHED;
 
 #ifdef CONFIG_SMP
 	/* zero means no -deadline tasks */
@@ -328,7 +328,7 @@ void init_dl_rq(struct dl_rq *dl_rq)
 
 	dl_rq->dl_nr_migratory = 0;
 	dl_rq->overloaded = 0;
-	dl_rq->pushable_dl_tasks_root = RB_ROOT;
+	dl_rq->pushable_dl_tasks_root = RB_ROOT_CACHED;
 #else
 	init_dl_bw(&dl_rq->dl_bw);
 #endif
@@ -410,10 +410,10 @@ static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
 static void enqueue_pushable_dl_task(struct rq *rq, struct task_struct *p)
 {
 	struct dl_rq *dl_rq = &rq->dl;
-	struct rb_node **link = &dl_rq->pushable_dl_tasks_root.rb_node;
+	struct rb_node **link = &dl_rq->pushable_dl_tasks_root.rb_root.rb_node;
 	struct rb_node *parent = NULL;
 	struct task_struct *entry;
-	int leftmost = 1;
+	bool leftmost = true;
 
 	BUG_ON(!RB_EMPTY_NODE(&p->pushable_dl_tasks));
 
@@ -425,17 +425,16 @@ static void enqueue_pushable_dl_task(struct rq *rq, struct task_struct *p)
 			link = &parent->rb_left;
 		else {
 			link = &parent->rb_right;
-			leftmost = 0;
+			leftmost = false;
 		}
 	}
 
-	if (leftmost) {
-		dl_rq->pushable_dl_tasks_leftmost = &p->pushable_dl_tasks;
+	if (leftmost)
 		dl_rq->earliest_dl.next = p->dl.deadline;
-	}
 
 	rb_link_node(&p->pushable_dl_tasks, parent, link);
-	rb_insert_color(&p->pushable_dl_tasks, &dl_rq->pushable_dl_tasks_root);
+	rb_insert_color_cached(&p->pushable_dl_tasks,
+			       &dl_rq->pushable_dl_tasks_root, leftmost);
 }
 
 static void dequeue_pushable_dl_task(struct rq *rq, struct task_struct *p)
@@ -445,24 +444,23 @@ static void dequeue_pushable_dl_task(struct rq *rq, struct task_struct *p)
 	if (RB_EMPTY_NODE(&p->pushable_dl_tasks))
 		return;
 
-	if (dl_rq->pushable_dl_tasks_leftmost == &p->pushable_dl_tasks) {
+	if (dl_rq->pushable_dl_tasks_root.rb_leftmost == &p->pushable_dl_tasks) {
 		struct rb_node *next_node;
 
 		next_node = rb_next(&p->pushable_dl_tasks);
-		dl_rq->pushable_dl_tasks_leftmost = next_node;
 		if (next_node) {
 			dl_rq->earliest_dl.next = rb_entry(next_node,
 				struct task_struct, pushable_dl_tasks)->dl.deadline;
 		}
 	}
 
-	rb_erase(&p->pushable_dl_tasks, &dl_rq->pushable_dl_tasks_root);
+	rb_erase_cached(&p->pushable_dl_tasks, &dl_rq->pushable_dl_tasks_root);
 	RB_CLEAR_NODE(&p->pushable_dl_tasks);
 }
 
 static inline int has_pushable_dl_tasks(struct rq *rq)
 {
-	return !RB_EMPTY_ROOT(&rq->dl.pushable_dl_tasks_root);
+	return !RB_EMPTY_ROOT(&rq->dl.pushable_dl_tasks_root.rb_root);
 }
 
 static int push_dl_task(struct rq *rq);
@@ -1266,7 +1264,7 @@ static void dec_dl_deadline(struct dl_rq *dl_rq, u64 deadline)
 		dl_rq->earliest_dl.next = 0;
 		cpudl_clear(&rq->rd->cpudl, rq->cpu);
 	} else {
-		struct rb_node *leftmost = dl_rq->rb_leftmost;
+		struct rb_node *leftmost = dl_rq->root.rb_leftmost;
 		struct sched_dl_entity *entry;
 
 		entry = rb_entry(leftmost, struct sched_dl_entity, rb_node);
@@ -1313,7 +1311,7 @@ void dec_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
 static void __enqueue_dl_entity(struct sched_dl_entity *dl_se)
 {
 	struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
-	struct rb_node **link = &dl_rq->rb_root.rb_node;
+	struct rb_node **link = &dl_rq->root.rb_root.rb_node;
 	struct rb_node *parent = NULL;
 	struct sched_dl_entity *entry;
 	int leftmost = 1;
@@ -1331,11 +1329,8 @@ static void __enqueue_dl_entity(struct sched_dl_entity *dl_se)
 		}
 	}
 
-	if (leftmost)
-		dl_rq->rb_leftmost = &dl_se->rb_node;
-
 	rb_link_node(&dl_se->rb_node, parent, link);
-	rb_insert_color(&dl_se->rb_node, &dl_rq->rb_root);
+	rb_insert_color_cached(&dl_se->rb_node, &dl_rq->root, leftmost);
 
 	inc_dl_tasks(dl_se, dl_rq);
 }
@@ -1347,14 +1342,7 @@ static void __dequeue_dl_entity(struct sched_dl_entity *dl_se)
 	if (RB_EMPTY_NODE(&dl_se->rb_node))
 		return;
 
-	if (dl_rq->rb_leftmost == &dl_se->rb_node) {
-		struct rb_node *next_node;
-
-		next_node = rb_next(&dl_se->rb_node);
-		dl_rq->rb_leftmost = next_node;
-	}
-
-	rb_erase(&dl_se->rb_node, &dl_rq->rb_root);
+	rb_erase_cached(&dl_se->rb_node, &dl_rq->root);
 	RB_CLEAR_NODE(&dl_se->rb_node);
 
 	dec_dl_tasks(dl_se, dl_rq);
@@ -1647,7 +1635,7 @@ static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
 static struct sched_dl_entity *pick_next_dl_entity(struct rq *rq,
 						   struct dl_rq *dl_rq)
 {
-	struct rb_node *left = dl_rq->rb_leftmost;
+	struct rb_node *left = rb_first_cached(&dl_rq->root);
 
 	if (!left)
 		return NULL;
@@ -1771,7 +1759,7 @@ static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu)
  */
 static struct task_struct *pick_earliest_pushable_dl_task(struct rq *rq, int cpu)
 {
-	struct rb_node *next_node = rq->dl.pushable_dl_tasks_leftmost;
+	struct rb_node *next_node = rq->dl.pushable_dl_tasks_root.rb_leftmost;
 	struct task_struct *p = NULL;
 
 	if (!has_pushable_dl_tasks(rq))
@@ -1945,7 +1933,7 @@ static struct task_struct *pick_next_pushable_dl_task(struct rq *rq)
 	if (!has_pushable_dl_tasks(rq))
 		return NULL;
 
-	p = rb_entry(rq->dl.pushable_dl_tasks_leftmost,
+	p = rb_entry(rq->dl.pushable_dl_tasks_root.rb_leftmost,
 		     struct task_struct, pushable_dl_tasks);
 
 	BUG_ON(rq->cpu != task_cpu(p));
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 4a23bbc..8e536d9 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -530,7 +530,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 			SPLIT_NS(cfs_rq->exec_clock));
 
 	raw_spin_lock_irqsave(&rq->lock, flags);
-	if (cfs_rq->rb_leftmost)
+	if (rb_first_cached(&cfs_rq->tasks_timeline))
 		MIN_vruntime = (__pick_first_entity(cfs_rq))->vruntime;
 	last = __pick_last_entity(cfs_rq);
 	if (last)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 8bc0a88..a5d83ed 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -513,6 +513,7 @@ static inline int entity_before(struct sched_entity *a,
 static void update_min_vruntime(struct cfs_rq *cfs_rq)
 {
 	struct sched_entity *curr = cfs_rq->curr;
+	struct rb_node *leftmost = rb_first_cached(&cfs_rq->tasks_timeline);
 
 	u64 vruntime = cfs_rq->min_vruntime;
 
@@ -523,10 +524,9 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
 			curr = NULL;
 	}
 
-	if (cfs_rq->rb_leftmost) {
-		struct sched_entity *se = rb_entry(cfs_rq->rb_leftmost,
-						   struct sched_entity,
-						   run_node);
+	if (leftmost) { /* non-empty tree */
+		struct sched_entity *se;
+		se = rb_entry(leftmost, struct sched_entity, run_node);
 
 		if (!curr)
 			vruntime = se->vruntime;
@@ -547,10 +547,10 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
  */
 static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-	struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
+	struct rb_node **link = &cfs_rq->tasks_timeline.rb_root.rb_node;
 	struct rb_node *parent = NULL;
 	struct sched_entity *entry;
-	int leftmost = 1;
+	bool leftmost = true;
 
 	/*
 	 * Find the right place in the rbtree:
@@ -566,36 +566,23 @@ static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 			link = &parent->rb_left;
 		} else {
 			link = &parent->rb_right;
-			leftmost = 0;
+			leftmost = false;
 		}
 	}
 
-	/*
-	 * Maintain a cache of leftmost tree entries (it is frequently
-	 * used):
-	 */
-	if (leftmost)
-		cfs_rq->rb_leftmost = &se->run_node;
-
 	rb_link_node(&se->run_node, parent, link);
-	rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
+	rb_insert_color_cached(&se->run_node,
+			       &cfs_rq->tasks_timeline, leftmost);
 }
 
 static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-	if (cfs_rq->rb_leftmost == &se->run_node) {
-		struct rb_node *next_node;
-
-		next_node = rb_next(&se->run_node);
-		cfs_rq->rb_leftmost = next_node;
-	}
-
-	rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
+	rb_erase_cached(&se->run_node, &cfs_rq->tasks_timeline);
 }
 
 struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
 {
-	struct rb_node *left = cfs_rq->rb_leftmost;
+	struct rb_node *left = rb_first_cached(&cfs_rq->tasks_timeline);
 
 	if (!left)
 		return NULL;
@@ -616,7 +603,7 @@ static struct sched_entity *__pick_next_entity(struct sched_entity *se)
 #ifdef CONFIG_SCHED_DEBUG
 struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
 {
-	struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
+	struct rb_node *last = rb_last(&cfs_rq->tasks_timeline.rb_root);
 
 	if (!last)
 		return NULL;
@@ -9312,7 +9299,7 @@ static void set_curr_task_fair(struct rq *rq)
 
 void init_cfs_rq(struct cfs_rq *cfs_rq)
 {
-	cfs_rq->tasks_timeline = RB_ROOT;
+	cfs_rq->tasks_timeline = RB_ROOT_CACHED;
 	cfs_rq->min_vruntime = (u64)(-(1LL << 20));
 #ifndef CONFIG_64BIT
 	cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 6ed7962..746ac78 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -426,8 +426,7 @@ struct cfs_rq {
 	u64 min_vruntime_copy;
 #endif
 
-	struct rb_root tasks_timeline;
-	struct rb_node *rb_leftmost;
+	struct rb_root_cached tasks_timeline;
 
 	/*
 	 * 'curr' points to currently running entity on this cfs_rq.
@@ -550,8 +549,7 @@ struct rt_rq {
 /* Deadline class' related fields in a runqueue */
 struct dl_rq {
 	/* runqueue is an rbtree, ordered by deadline */
-	struct rb_root rb_root;
-	struct rb_node *rb_leftmost;
+	struct rb_root_cached root;
 
 	unsigned long dl_nr_running;
 
@@ -575,8 +573,7 @@ struct dl_rq {
 	 * an rb-tree, ordered by tasks' deadlines, with caching
 	 * of the leftmost (earliest deadline) element.
 	 */
-	struct rb_root pushable_dl_tasks_root;
-	struct rb_node *pushable_dl_tasks_leftmost;
+	struct rb_root_cached pushable_dl_tasks_root;
 #else
 	struct dl_bw dl_bw;
 #endif
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 6f7b439..5d0062c 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -473,7 +473,7 @@ static int __init isolated_cpu_setup(char *str)
 	alloc_bootmem_cpumask_var(&cpu_isolated_map);
 	ret = cpulist_parse(str, cpu_isolated_map);
 	if (ret) {
-		pr_err("sched: Error, all isolcpus= values must be between 0 and %d\n", nr_cpu_ids);
+		pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids);
 		return 0;
 	}
 	return 1;
diff --git a/kernel/smp.c b/kernel/smp.c
index 81cfca9..c94dd85 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -550,7 +550,7 @@ static int __init maxcpus(char *str)
 early_param("maxcpus", maxcpus);
 
 /* Setup number of possible processor ids */
-int nr_cpu_ids __read_mostly = NR_CPUS;
+unsigned int nr_cpu_ids __read_mostly = NR_CPUS;
 EXPORT_SYMBOL(nr_cpu_ids);
 
 /* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 8ea4fb3..2cafb49 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -2316,7 +2316,7 @@ void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)
 	raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
 }
 EXPORT_SYMBOL(hardpps);
-#endif
+#endif /* CONFIG_NTP_PPS */
 
 /**
  * xtime_update() - advances the timekeeping infrastructure
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index d56123c..b8f1f54 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -1543,7 +1543,7 @@ fs_initcall(init_graph_tracefs);
 
 static __init int init_graph_trace(void)
 {
-	max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
+	max_bytes_for_cpu = snprintf(NULL, 0, "%u", nr_cpu_ids - 1);
 
 	if (!register_trace_event(&graph_trace_entry_event)) {
 		pr_warn("Warning: could not register graph trace events\n");
diff --git a/kernel/umh.c b/kernel/umh.c
new file mode 100644
index 0000000..6ff9905
--- /dev/null
+++ b/kernel/umh.c
@@ -0,0 +1,568 @@
+/*
+ * umh - the kernel usermode helper
+ */
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/sched/task.h>
+#include <linux/binfmts.h>
+#include <linux/syscalls.h>
+#include <linux/unistd.h>
+#include <linux/kmod.h>
+#include <linux/slab.h>
+#include <linux/completion.h>
+#include <linux/cred.h>
+#include <linux/file.h>
+#include <linux/fdtable.h>
+#include <linux/workqueue.h>
+#include <linux/security.h>
+#include <linux/mount.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/resource.h>
+#include <linux/notifier.h>
+#include <linux/suspend.h>
+#include <linux/rwsem.h>
+#include <linux/ptrace.h>
+#include <linux/async.h>
+#include <linux/uaccess.h>
+
+#include <trace/events/module.h>
+
+#define CAP_BSET	(void *)1
+#define CAP_PI		(void *)2
+
+static kernel_cap_t usermodehelper_bset = CAP_FULL_SET;
+static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET;
+static DEFINE_SPINLOCK(umh_sysctl_lock);
+static DECLARE_RWSEM(umhelper_sem);
+
+static void call_usermodehelper_freeinfo(struct subprocess_info *info)
+{
+	if (info->cleanup)
+		(*info->cleanup)(info);
+	kfree(info);
+}
+
+static void umh_complete(struct subprocess_info *sub_info)
+{
+	struct completion *comp = xchg(&sub_info->complete, NULL);
+	/*
+	 * See call_usermodehelper_exec(). If xchg() returns NULL
+	 * we own sub_info, the UMH_KILLABLE caller has gone away
+	 * or the caller used UMH_NO_WAIT.
+	 */
+	if (comp)
+		complete(comp);
+	else
+		call_usermodehelper_freeinfo(sub_info);
+}
+
+/*
+ * This is the task which runs the usermode application
+ */
+static int call_usermodehelper_exec_async(void *data)
+{
+	struct subprocess_info *sub_info = data;
+	struct cred *new;
+	int retval;
+
+	spin_lock_irq(&current->sighand->siglock);
+	flush_signal_handlers(current, 1);
+	spin_unlock_irq(&current->sighand->siglock);
+
+	/*
+	 * Our parent (unbound workqueue) runs with elevated scheduling
+	 * priority. Avoid propagating that into the userspace child.
+	 */
+	set_user_nice(current, 0);
+
+	retval = -ENOMEM;
+	new = prepare_kernel_cred(current);
+	if (!new)
+		goto out;
+
+	spin_lock(&umh_sysctl_lock);
+	new->cap_bset = cap_intersect(usermodehelper_bset, new->cap_bset);
+	new->cap_inheritable = cap_intersect(usermodehelper_inheritable,
+					     new->cap_inheritable);
+	spin_unlock(&umh_sysctl_lock);
+
+	if (sub_info->init) {
+		retval = sub_info->init(sub_info, new);
+		if (retval) {
+			abort_creds(new);
+			goto out;
+		}
+	}
+
+	commit_creds(new);
+
+	retval = do_execve(getname_kernel(sub_info->path),
+			   (const char __user *const __user *)sub_info->argv,
+			   (const char __user *const __user *)sub_info->envp);
+out:
+	sub_info->retval = retval;
+	/*
+	 * call_usermodehelper_exec_sync() will call umh_complete
+	 * if UHM_WAIT_PROC.
+	 */
+	if (!(sub_info->wait & UMH_WAIT_PROC))
+		umh_complete(sub_info);
+	if (!retval)
+		return 0;
+	do_exit(0);
+}
+
+/* Handles UMH_WAIT_PROC.  */
+static void call_usermodehelper_exec_sync(struct subprocess_info *sub_info)
+{
+	pid_t pid;
+
+	/* If SIGCLD is ignored sys_wait4 won't populate the status. */
+	kernel_sigaction(SIGCHLD, SIG_DFL);
+	pid = kernel_thread(call_usermodehelper_exec_async, sub_info, SIGCHLD);
+	if (pid < 0) {
+		sub_info->retval = pid;
+	} else {
+		int ret = -ECHILD;
+		/*
+		 * Normally it is bogus to call wait4() from in-kernel because
+		 * wait4() wants to write the exit code to a userspace address.
+		 * But call_usermodehelper_exec_sync() always runs as kernel
+		 * thread (workqueue) and put_user() to a kernel address works
+		 * OK for kernel threads, due to their having an mm_segment_t
+		 * which spans the entire address space.
+		 *
+		 * Thus the __user pointer cast is valid here.
+		 */
+		sys_wait4(pid, (int __user *)&ret, 0, NULL);
+
+		/*
+		 * If ret is 0, either call_usermodehelper_exec_async failed and
+		 * the real error code is already in sub_info->retval or
+		 * sub_info->retval is 0 anyway, so don't mess with it then.
+		 */
+		if (ret)
+			sub_info->retval = ret;
+	}
+
+	/* Restore default kernel sig handler */
+	kernel_sigaction(SIGCHLD, SIG_IGN);
+
+	umh_complete(sub_info);
+}
+
+/*
+ * We need to create the usermodehelper kernel thread from a task that is affine
+ * to an optimized set of CPUs (or nohz housekeeping ones) such that they
+ * inherit a widest affinity irrespective of call_usermodehelper() callers with
+ * possibly reduced affinity (eg: per-cpu workqueues). We don't want
+ * usermodehelper targets to contend a busy CPU.
+ *
+ * Unbound workqueues provide such wide affinity and allow to block on
+ * UMH_WAIT_PROC requests without blocking pending request (up to some limit).
+ *
+ * Besides, workqueues provide the privilege level that caller might not have
+ * to perform the usermodehelper request.
+ *
+ */
+static void call_usermodehelper_exec_work(struct work_struct *work)
+{
+	struct subprocess_info *sub_info =
+		container_of(work, struct subprocess_info, work);
+
+	if (sub_info->wait & UMH_WAIT_PROC) {
+		call_usermodehelper_exec_sync(sub_info);
+	} else {
+		pid_t pid;
+		/*
+		 * Use CLONE_PARENT to reparent it to kthreadd; we do not
+		 * want to pollute current->children, and we need a parent
+		 * that always ignores SIGCHLD to ensure auto-reaping.
+		 */
+		pid = kernel_thread(call_usermodehelper_exec_async, sub_info,
+				    CLONE_PARENT | SIGCHLD);
+		if (pid < 0) {
+			sub_info->retval = pid;
+			umh_complete(sub_info);
+		}
+	}
+}
+
+/*
+ * If set, call_usermodehelper_exec() will exit immediately returning -EBUSY
+ * (used for preventing user land processes from being created after the user
+ * land has been frozen during a system-wide hibernation or suspend operation).
+ * Should always be manipulated under umhelper_sem acquired for write.
+ */
+static enum umh_disable_depth usermodehelper_disabled = UMH_DISABLED;
+
+/* Number of helpers running */
+static atomic_t running_helpers = ATOMIC_INIT(0);
+
+/*
+ * Wait queue head used by usermodehelper_disable() to wait for all running
+ * helpers to finish.
+ */
+static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq);
+
+/*
+ * Used by usermodehelper_read_lock_wait() to wait for usermodehelper_disabled
+ * to become 'false'.
+ */
+static DECLARE_WAIT_QUEUE_HEAD(usermodehelper_disabled_waitq);
+
+/*
+ * Time to wait for running_helpers to become zero before the setting of
+ * usermodehelper_disabled in usermodehelper_disable() fails
+ */
+#define RUNNING_HELPERS_TIMEOUT	(5 * HZ)
+
+int usermodehelper_read_trylock(void)
+{
+	DEFINE_WAIT(wait);
+	int ret = 0;
+
+	down_read(&umhelper_sem);
+	for (;;) {
+		prepare_to_wait(&usermodehelper_disabled_waitq, &wait,
+				TASK_INTERRUPTIBLE);
+		if (!usermodehelper_disabled)
+			break;
+
+		if (usermodehelper_disabled == UMH_DISABLED)
+			ret = -EAGAIN;
+
+		up_read(&umhelper_sem);
+
+		if (ret)
+			break;
+
+		schedule();
+		try_to_freeze();
+
+		down_read(&umhelper_sem);
+	}
+	finish_wait(&usermodehelper_disabled_waitq, &wait);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(usermodehelper_read_trylock);
+
+long usermodehelper_read_lock_wait(long timeout)
+{
+	DEFINE_WAIT(wait);
+
+	if (timeout < 0)
+		return -EINVAL;
+
+	down_read(&umhelper_sem);
+	for (;;) {
+		prepare_to_wait(&usermodehelper_disabled_waitq, &wait,
+				TASK_UNINTERRUPTIBLE);
+		if (!usermodehelper_disabled)
+			break;
+
+		up_read(&umhelper_sem);
+
+		timeout = schedule_timeout(timeout);
+		if (!timeout)
+			break;
+
+		down_read(&umhelper_sem);
+	}
+	finish_wait(&usermodehelper_disabled_waitq, &wait);
+	return timeout;
+}
+EXPORT_SYMBOL_GPL(usermodehelper_read_lock_wait);
+
+void usermodehelper_read_unlock(void)
+{
+	up_read(&umhelper_sem);
+}
+EXPORT_SYMBOL_GPL(usermodehelper_read_unlock);
+
+/**
+ * __usermodehelper_set_disable_depth - Modify usermodehelper_disabled.
+ * @depth: New value to assign to usermodehelper_disabled.
+ *
+ * Change the value of usermodehelper_disabled (under umhelper_sem locked for
+ * writing) and wakeup tasks waiting for it to change.
+ */
+void __usermodehelper_set_disable_depth(enum umh_disable_depth depth)
+{
+	down_write(&umhelper_sem);
+	usermodehelper_disabled = depth;
+	wake_up(&usermodehelper_disabled_waitq);
+	up_write(&umhelper_sem);
+}
+
+/**
+ * __usermodehelper_disable - Prevent new helpers from being started.
+ * @depth: New value to assign to usermodehelper_disabled.
+ *
+ * Set usermodehelper_disabled to @depth and wait for running helpers to exit.
+ */
+int __usermodehelper_disable(enum umh_disable_depth depth)
+{
+	long retval;
+
+	if (!depth)
+		return -EINVAL;
+
+	down_write(&umhelper_sem);
+	usermodehelper_disabled = depth;
+	up_write(&umhelper_sem);
+
+	/*
+	 * From now on call_usermodehelper_exec() won't start any new
+	 * helpers, so it is sufficient if running_helpers turns out to
+	 * be zero at one point (it may be increased later, but that
+	 * doesn't matter).
+	 */
+	retval = wait_event_timeout(running_helpers_waitq,
+					atomic_read(&running_helpers) == 0,
+					RUNNING_HELPERS_TIMEOUT);
+	if (retval)
+		return 0;
+
+	__usermodehelper_set_disable_depth(UMH_ENABLED);
+	return -EAGAIN;
+}
+
+static void helper_lock(void)
+{
+	atomic_inc(&running_helpers);
+	smp_mb__after_atomic();
+}
+
+static void helper_unlock(void)
+{
+	if (atomic_dec_and_test(&running_helpers))
+		wake_up(&running_helpers_waitq);
+}
+
+/**
+ * call_usermodehelper_setup - prepare to call a usermode helper
+ * @path: path to usermode executable
+ * @argv: arg vector for process
+ * @envp: environment for process
+ * @gfp_mask: gfp mask for memory allocation
+ * @cleanup: a cleanup function
+ * @init: an init function
+ * @data: arbitrary context sensitive data
+ *
+ * Returns either %NULL on allocation failure, or a subprocess_info
+ * structure.  This should be passed to call_usermodehelper_exec to
+ * exec the process and free the structure.
+ *
+ * The init function is used to customize the helper process prior to
+ * exec.  A non-zero return code causes the process to error out, exit,
+ * and return the failure to the calling process
+ *
+ * The cleanup function is just before ethe subprocess_info is about to
+ * be freed.  This can be used for freeing the argv and envp.  The
+ * Function must be runnable in either a process context or the
+ * context in which call_usermodehelper_exec is called.
+ */
+struct subprocess_info *call_usermodehelper_setup(const char *path, char **argv,
+		char **envp, gfp_t gfp_mask,
+		int (*init)(struct subprocess_info *info, struct cred *new),
+		void (*cleanup)(struct subprocess_info *info),
+		void *data)
+{
+	struct subprocess_info *sub_info;
+	sub_info = kzalloc(sizeof(struct subprocess_info), gfp_mask);
+	if (!sub_info)
+		goto out;
+
+	INIT_WORK(&sub_info->work, call_usermodehelper_exec_work);
+
+#ifdef CONFIG_STATIC_USERMODEHELPER
+	sub_info->path = CONFIG_STATIC_USERMODEHELPER_PATH;
+#else
+	sub_info->path = path;
+#endif
+	sub_info->argv = argv;
+	sub_info->envp = envp;
+
+	sub_info->cleanup = cleanup;
+	sub_info->init = init;
+	sub_info->data = data;
+  out:
+	return sub_info;
+}
+EXPORT_SYMBOL(call_usermodehelper_setup);
+
+/**
+ * call_usermodehelper_exec - start a usermode application
+ * @sub_info: information about the subprocessa
+ * @wait: wait for the application to finish and return status.
+ *        when UMH_NO_WAIT don't wait at all, but you get no useful error back
+ *        when the program couldn't be exec'ed. This makes it safe to call
+ *        from interrupt context.
+ *
+ * Runs a user-space application.  The application is started
+ * asynchronously if wait is not set, and runs as a child of system workqueues.
+ * (ie. it runs with full root capabilities and optimized affinity).
+ */
+int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
+{
+	DECLARE_COMPLETION_ONSTACK(done);
+	int retval = 0;
+
+	if (!sub_info->path) {
+		call_usermodehelper_freeinfo(sub_info);
+		return -EINVAL;
+	}
+	helper_lock();
+	if (usermodehelper_disabled) {
+		retval = -EBUSY;
+		goto out;
+	}
+
+	/*
+	 * If there is no binary for us to call, then just return and get out of
+	 * here.  This allows us to set STATIC_USERMODEHELPER_PATH to "" and
+	 * disable all call_usermodehelper() calls.
+	 */
+	if (strlen(sub_info->path) == 0)
+		goto out;
+
+	/*
+	 * Set the completion pointer only if there is a waiter.
+	 * This makes it possible to use umh_complete to free
+	 * the data structure in case of UMH_NO_WAIT.
+	 */
+	sub_info->complete = (wait == UMH_NO_WAIT) ? NULL : &done;
+	sub_info->wait = wait;
+
+	queue_work(system_unbound_wq, &sub_info->work);
+	if (wait == UMH_NO_WAIT)	/* task has freed sub_info */
+		goto unlock;
+
+	if (wait & UMH_KILLABLE) {
+		retval = wait_for_completion_killable(&done);
+		if (!retval)
+			goto wait_done;
+
+		/* umh_complete() will see NULL and free sub_info */
+		if (xchg(&sub_info->complete, NULL))
+			goto unlock;
+		/* fallthrough, umh_complete() was already called */
+	}
+
+	wait_for_completion(&done);
+wait_done:
+	retval = sub_info->retval;
+out:
+	call_usermodehelper_freeinfo(sub_info);
+unlock:
+	helper_unlock();
+	return retval;
+}
+EXPORT_SYMBOL(call_usermodehelper_exec);
+
+/**
+ * call_usermodehelper() - prepare and start a usermode application
+ * @path: path to usermode executable
+ * @argv: arg vector for process
+ * @envp: environment for process
+ * @wait: wait for the application to finish and return status.
+ *        when UMH_NO_WAIT don't wait at all, but you get no useful error back
+ *        when the program couldn't be exec'ed. This makes it safe to call
+ *        from interrupt context.
+ *
+ * This function is the equivalent to use call_usermodehelper_setup() and
+ * call_usermodehelper_exec().
+ */
+int call_usermodehelper(const char *path, char **argv, char **envp, int wait)
+{
+	struct subprocess_info *info;
+	gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
+
+	info = call_usermodehelper_setup(path, argv, envp, gfp_mask,
+					 NULL, NULL, NULL);
+	if (info == NULL)
+		return -ENOMEM;
+
+	return call_usermodehelper_exec(info, wait);
+}
+EXPORT_SYMBOL(call_usermodehelper);
+
+static int proc_cap_handler(struct ctl_table *table, int write,
+			 void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	struct ctl_table t;
+	unsigned long cap_array[_KERNEL_CAPABILITY_U32S];
+	kernel_cap_t new_cap;
+	int err, i;
+
+	if (write && (!capable(CAP_SETPCAP) ||
+		      !capable(CAP_SYS_MODULE)))
+		return -EPERM;
+
+	/*
+	 * convert from the global kernel_cap_t to the ulong array to print to
+	 * userspace if this is a read.
+	 */
+	spin_lock(&umh_sysctl_lock);
+	for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++)  {
+		if (table->data == CAP_BSET)
+			cap_array[i] = usermodehelper_bset.cap[i];
+		else if (table->data == CAP_PI)
+			cap_array[i] = usermodehelper_inheritable.cap[i];
+		else
+			BUG();
+	}
+	spin_unlock(&umh_sysctl_lock);
+
+	t = *table;
+	t.data = &cap_array;
+
+	/*
+	 * actually read or write and array of ulongs from userspace.  Remember
+	 * these are least significant 32 bits first
+	 */
+	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
+	if (err < 0)
+		return err;
+
+	/*
+	 * convert from the sysctl array of ulongs to the kernel_cap_t
+	 * internal representation
+	 */
+	for (i = 0; i < _KERNEL_CAPABILITY_U32S; i++)
+		new_cap.cap[i] = cap_array[i];
+
+	/*
+	 * Drop everything not in the new_cap (but don't add things)
+	 */
+	spin_lock(&umh_sysctl_lock);
+	if (write) {
+		if (table->data == CAP_BSET)
+			usermodehelper_bset = cap_intersect(usermodehelper_bset, new_cap);
+		if (table->data == CAP_PI)
+			usermodehelper_inheritable = cap_intersect(usermodehelper_inheritable, new_cap);
+	}
+	spin_unlock(&umh_sysctl_lock);
+
+	return 0;
+}
+
+struct ctl_table usermodehelper_table[] = {
+	{
+		.procname	= "bset",
+		.data		= CAP_BSET,
+		.maxlen		= _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
+		.mode		= 0600,
+		.proc_handler	= proc_cap_handler,
+	},
+	{
+		.procname	= "inheritable",
+		.data		= CAP_PI,
+		.maxlen		= _KERNEL_CAPABILITY_U32S * sizeof(unsigned long),
+		.mode		= 0600,
+		.proc_handler	= proc_cap_handler,
+	},
+	{ }
+};