diff --git a/fs/proc/base.c b/fs/proc/base.c
index 7e9f07b..ebea950 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -59,6 +59,7 @@
 #include <linux/capability.h>
 #include <linux/file.h>
 #include <linux/fdtable.h>
+#include <linux/generic-radix-tree.h>
 #include <linux/string.h>
 #include <linux/seq_file.h>
 #include <linux/namei.h>
@@ -92,7 +93,6 @@
 #include <linux/sched/coredump.h>
 #include <linux/sched/debug.h>
 #include <linux/sched/stat.h>
-#include <linux/flex_array.h>
 #include <linux/posix-timers.h>
 #include <trace/events/oom.h>
 #include "internal.h"
@@ -140,9 +140,13 @@
 #define REG(NAME, MODE, fops)				\
 	NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
 #define ONE(NAME, MODE, show)				\
-	NOD(NAME, (S_IFREG|(MODE)), 			\
+	NOD(NAME, (S_IFREG|(MODE)),			\
 		NULL, &proc_single_file_operations,	\
 		{ .proc_show = show } )
+#define ATTR(LSM, NAME, MODE)				\
+	NOD(NAME, (S_IFREG|(MODE)),			\
+		NULL, &proc_pid_attr_operations,	\
+		{ .lsm = LSM })
 
 /*
  * Count the number of hardlinks for the pid_entry table, excluding the .
@@ -205,12 +209,53 @@
 	return result;
 }
 
+/*
+ * If the user used setproctitle(), we just get the string from
+ * user space at arg_start, and limit it to a maximum of one page.
+ */
+static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf,
+				size_t count, unsigned long pos,
+				unsigned long arg_start)
+{
+	char *page;
+	int ret, got;
+
+	if (pos >= PAGE_SIZE)
+		return 0;
+
+	page = (char *)__get_free_page(GFP_KERNEL);
+	if (!page)
+		return -ENOMEM;
+
+	ret = 0;
+	got = access_remote_vm(mm, arg_start, page, PAGE_SIZE, FOLL_ANON);
+	if (got > 0) {
+		int len = strnlen(page, got);
+
+		/* Include the NUL character if it was found */
+		if (len < got)
+			len++;
+
+		if (len > pos) {
+			len -= pos;
+			if (len > count)
+				len = count;
+			len -= copy_to_user(buf, page+pos, len);
+			if (!len)
+				len = -EFAULT;
+			ret = len;
+		}
+	}
+	free_page((unsigned long)page);
+	return ret;
+}
+
 static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf,
 			      size_t count, loff_t *ppos)
 {
 	unsigned long arg_start, arg_end, env_start, env_end;
 	unsigned long pos, len;
-	char *page;
+	char *page, c;
 
 	/* Check if process spawned far enough to have cmdline. */
 	if (!mm->env_end)
@@ -227,28 +272,42 @@
 		return 0;
 
 	/*
-	 * We have traditionally allowed the user to re-write
-	 * the argument strings and overflow the end result
-	 * into the environment section. But only do that if
-	 * the environment area is contiguous to the arguments.
+	 * We allow setproctitle() to overwrite the argument
+	 * strings, and overflow past the original end. But
+	 * only when it overflows into the environment area.
 	 */
-	if (env_start != arg_end || env_start >= env_end)
+	if (env_start != arg_end || env_end < env_start)
 		env_start = env_end = arg_end;
-
-	/* .. and limit it to a maximum of one page of slop */
-	if (env_end >= arg_end + PAGE_SIZE)
-		env_end = arg_end + PAGE_SIZE - 1;
+	len = env_end - arg_start;
 
 	/* We're not going to care if "*ppos" has high bits set */
-	pos = arg_start + *ppos;
-
-	/* .. but we do check the result is in the proper range */
-	if (pos < arg_start || pos >= env_end)
+	pos = *ppos;
+	if (pos >= len)
+		return 0;
+	if (count > len - pos)
+		count = len - pos;
+	if (!count)
 		return 0;
 
-	/* .. and we never go past env_end */
-	if (env_end - pos < count)
-		count = env_end - pos;
+	/*
+	 * Magical special case: if the argv[] end byte is not
+	 * zero, the user has overwritten it with setproctitle(3).
+	 *
+	 * Possible future enhancement: do this only once when
+	 * pos is 0, and set a flag in the 'struct file'.
+	 */
+	if (access_remote_vm(mm, arg_end-1, &c, 1, FOLL_ANON) == 1 && c)
+		return get_mm_proctitle(mm, buf, count, pos, arg_start);
+
+	/*
+	 * For the non-setproctitle() case we limit things strictly
+	 * to the [arg_start, arg_end[ range.
+	 */
+	pos += arg_start;
+	if (pos < arg_start || pos >= arg_end)
+		return 0;
+	if (count > arg_end - pos)
+		count = arg_end - pos;
 
 	page = (char *)__get_free_page(GFP_KERNEL);
 	if (!page)
@@ -258,48 +317,11 @@
 	while (count) {
 		int got;
 		size_t size = min_t(size_t, PAGE_SIZE, count);
-		long offset;
 
-		/*
-		 * Are we already starting past the official end?
-		 * We always include the last byte that is *supposed*
-		 * to be NUL
-		 */
-		offset = (pos >= arg_end) ? pos - arg_end + 1 : 0;
-
-		got = access_remote_vm(mm, pos - offset, page, size + offset, FOLL_ANON);
-		if (got <= offset)
+		got = access_remote_vm(mm, pos, page, size, FOLL_ANON);
+		if (got <= 0)
 			break;
-		got -= offset;
-
-		/* Don't walk past a NUL character once you hit arg_end */
-		if (pos + got >= arg_end) {
-			int n = 0;
-
-			/*
-			 * If we started before 'arg_end' but ended up
-			 * at or after it, we start the NUL character
-			 * check at arg_end-1 (where we expect the normal
-			 * EOF to be).
-			 *
-			 * NOTE! This is smaller than 'got', because
-			 * pos + got >= arg_end
-			 */
-			if (pos < arg_end)
-				n = arg_end - pos - 1;
-
-			/* Cut off at first NUL after 'n' */
-			got = n + strnlen(page+n, offset+got-n);
-			if (got < offset)
-				break;
-			got -= offset;
-
-			/* Include the NUL if it existed */
-			if (got < size)
-				got++;
-		}
-
-		got -= copy_to_user(buf, page+offset, got);
+		got -= copy_to_user(buf, page, got);
 		if (unlikely(!got)) {
 			if (!len)
 				len = -EFAULT;
@@ -403,7 +425,6 @@
 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
 			  struct pid *pid, struct task_struct *task)
 {
-	struct stack_trace trace;
 	unsigned long *entries;
 	int err;
 
@@ -426,20 +447,17 @@
 	if (!entries)
 		return -ENOMEM;
 
-	trace.nr_entries	= 0;
-	trace.max_entries	= MAX_STACK_TRACE_DEPTH;
-	trace.entries		= entries;
-	trace.skip		= 0;
-
 	err = lock_trace(task);
 	if (!err) {
-		unsigned int i;
+		unsigned int i, nr_entries;
 
-		save_stack_trace_tsk(task, &trace);
+		nr_entries = stack_trace_save_tsk(task, entries,
+						  MAX_STACK_TRACE_DEPTH, 0);
 
-		for (i = 0; i < trace.nr_entries; i++) {
+		for (i = 0; i < nr_entries; i++) {
 			seq_printf(m, "[<0>] %pB\n", (void *)entries[i]);
 		}
+
 		unlock_trace(task);
 	}
 	kfree(entries);
@@ -456,7 +474,7 @@
 			      struct pid *pid, struct task_struct *task)
 {
 	if (unlikely(!sched_info_on()))
-		seq_printf(m, "0 0 0\n");
+		seq_puts(m, "0 0 0\n");
 	else
 		seq_printf(m, "%llu %llu %lu\n",
 		   (unsigned long long)task->se.sum_exec_runtime,
@@ -485,10 +503,9 @@
 				   lr->count, lr->time, lr->max);
 			for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
 				unsigned long bt = lr->backtrace[q];
+
 				if (!bt)
 					break;
-				if (bt == ULONG_MAX)
-					break;
 				seq_printf(m, " %ps", (void *)bt);
 			}
 			seq_putc(m, '\n');
@@ -511,7 +528,7 @@
 
 	if (!task)
 		return -ESRCH;
-	clear_all_latency_tracing(task);
+	clear_tsk_latency_tracing(task);
 	put_task_struct(task);
 
 	return count;
@@ -530,11 +547,10 @@
 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
 			  struct pid *pid, struct task_struct *task)
 {
-	unsigned long totalpages = totalram_pages + total_swap_pages;
+	unsigned long totalpages = totalram_pages() + total_swap_pages;
 	unsigned long points = 0;
 
-	points = oom_badness(task, NULL, NULL, totalpages) *
-					1000 / totalpages;
+	points = oom_badness(task, totalpages) * 1000 / totalpages;
 	seq_printf(m, "%lu\n", points);
 
 	return 0;
@@ -581,8 +597,10 @@
 	/*
 	 * print the file header
 	 */
-       seq_printf(m, "%-25s %-20s %-20s %-10s\n",
-		  "Limit", "Soft Limit", "Hard Limit", "Units");
+	seq_puts(m, "Limit                     "
+		"Soft Limit           "
+		"Hard Limit           "
+		"Units     \n");
 
 	for (i = 0; i < RLIM_NLIMITS; i++) {
 		if (rlim[i].rlim_cur == RLIM_INFINITY)
@@ -610,24 +628,25 @@
 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
 			    struct pid *pid, struct task_struct *task)
 {
-	long nr;
-	unsigned long args[6], sp, pc;
+	struct syscall_info info;
+	u64 *args = &info.data.args[0];
 	int res;
 
 	res = lock_trace(task);
 	if (res)
 		return res;
 
-	if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
+	if (task_current_syscall(task, &info))
 		seq_puts(m, "running\n");
-	else if (nr < 0)
-		seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
+	else if (info.data.nr < 0)
+		seq_printf(m, "%d 0x%llx 0x%llx\n",
+			   info.data.nr, info.sp, info.data.instruction_pointer);
 	else
 		seq_printf(m,
-		       "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
-		       nr,
+		       "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n",
+		       info.data.nr,
 		       args[0], args[1], args[2], args[3], args[4], args[5],
-		       sp, pc);
+		       info.sp, info.data.instruction_pointer);
 	unlock_trace(task);
 
 	return 0;
@@ -1084,10 +1103,6 @@
 
 			task_lock(p);
 			if (!p->vfork_done && process_shares_mm(p, mm)) {
-				pr_info("updating oom_score_adj for %d (%s) from %d to %d because it shares mm with %d (%s). Report if this is unexpected.\n",
-						task_pid_nr(p), p->comm,
-						p->signal->oom_score_adj, oom_adj,
-						task_pid_nr(task), task->comm);
 				p->signal->oom_score_adj = oom_adj;
 				if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
 					p->signal->oom_score_adj_min = (short)oom_adj;
@@ -1208,7 +1223,7 @@
 	.llseek		= default_llseek,
 };
 
-#ifdef CONFIG_AUDITSYSCALL
+#ifdef CONFIG_AUDIT
 #define TMPBUFLEN 11
 static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
 				  size_t count, loff_t *ppos)
@@ -1964,9 +1979,12 @@
 		goto out;
 
 	if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
-		down_read(&mm->mmap_sem);
-		exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
-		up_read(&mm->mmap_sem);
+		status = down_read_killable(&mm->mmap_sem);
+		if (!status) {
+			exact_vma_exists = !!find_exact_vma(mm, vm_start,
+							    vm_end);
+			up_read(&mm->mmap_sem);
+		}
 	}
 
 	mmput(mm);
@@ -2012,8 +2030,11 @@
 	if (rc)
 		goto out_mmput;
 
+	rc = down_read_killable(&mm->mmap_sem);
+	if (rc)
+		goto out_mmput;
+
 	rc = -ENOENT;
-	down_read(&mm->mmap_sem);
 	vma = find_exact_vma(mm, vm_start, vm_end);
 	if (vma && vma->vm_file) {
 		*path = vma->vm_file->f_path;
@@ -2109,7 +2130,11 @@
 	if (!mm)
 		goto out_put_task;
 
-	down_read(&mm->mmap_sem);
+	result = ERR_PTR(-EINTR);
+	if (down_read_killable(&mm->mmap_sem))
+		goto out_put_mm;
+
+	result = ERR_PTR(-ENOENT);
 	vma = find_exact_vma(mm, vm_start, vm_end);
 	if (!vma)
 		goto out_no_vma;
@@ -2120,6 +2145,7 @@
 
 out_no_vma:
 	up_read(&mm->mmap_sem);
+out_put_mm:
 	mmput(mm);
 out_put_task:
 	put_task_struct(task);
@@ -2140,11 +2166,12 @@
 	struct task_struct *task;
 	struct mm_struct *mm;
 	unsigned long nr_files, pos, i;
-	struct flex_array *fa = NULL;
-	struct map_files_info info;
+	GENRADIX(struct map_files_info) fa;
 	struct map_files_info *p;
 	int ret;
 
+	genradix_init(&fa);
+
 	ret = -ENOENT;
 	task = get_proc_task(file_inode(file));
 	if (!task)
@@ -2161,7 +2188,12 @@
 	mm = get_task_mm(task);
 	if (!mm)
 		goto out_put_task;
-	down_read(&mm->mmap_sem);
+
+	ret = down_read_killable(&mm->mmap_sem);
+	if (ret) {
+		mmput(mm);
+		goto out_put_task;
+	}
 
 	nr_files = 0;
 
@@ -2176,35 +2208,22 @@
 	 */
 
 	for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
-		if (vma->vm_file && ++pos > ctx->pos)
-			nr_files++;
-	}
+		if (!vma->vm_file)
+			continue;
+		if (++pos <= ctx->pos)
+			continue;
 
-	if (nr_files) {
-		fa = flex_array_alloc(sizeof(info), nr_files,
-					GFP_KERNEL);
-		if (!fa || flex_array_prealloc(fa, 0, nr_files,
-						GFP_KERNEL)) {
+		p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL);
+		if (!p) {
 			ret = -ENOMEM;
-			if (fa)
-				flex_array_free(fa);
 			up_read(&mm->mmap_sem);
 			mmput(mm);
 			goto out_put_task;
 		}
-		for (i = 0, vma = mm->mmap, pos = 2; vma;
-				vma = vma->vm_next) {
-			if (!vma->vm_file)
-				continue;
-			if (++pos <= ctx->pos)
-				continue;
 
-			info.start = vma->vm_start;
-			info.end = vma->vm_end;
-			info.mode = vma->vm_file->f_mode;
-			if (flex_array_put(fa, i++, &info, GFP_KERNEL))
-				BUG();
-		}
+		p->start = vma->vm_start;
+		p->end = vma->vm_end;
+		p->mode = vma->vm_file->f_mode;
 	}
 	up_read(&mm->mmap_sem);
 	mmput(mm);
@@ -2213,7 +2232,7 @@
 		char buf[4 * sizeof(long) + 2];	/* max: %lx-%lx\0 */
 		unsigned int len;
 
-		p = flex_array_get(fa, i);
+		p = genradix_ptr(&fa, i);
 		len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);
 		if (!proc_fill_cache(file, ctx,
 				      buf, len,
@@ -2223,12 +2242,11 @@
 			break;
 		ctx->pos++;
 	}
-	if (fa)
-		flex_array_free(fa);
 
 out_put_task:
 	put_task_struct(task);
 out:
+	genradix_free(&fa);
 	return ret;
 }
 
@@ -2356,10 +2374,13 @@
 		return -ESRCH;
 
 	if (p != current) {
-		if (!capable(CAP_SYS_NICE)) {
+		rcu_read_lock();
+		if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
+			rcu_read_unlock();
 			count = -EPERM;
 			goto out;
 		}
+		rcu_read_unlock();
 
 		err = security_task_setscheduler(p);
 		if (err) {
@@ -2392,11 +2413,14 @@
 		return -ESRCH;
 
 	if (p != current) {
-
-		if (!capable(CAP_SYS_NICE)) {
+		rcu_read_lock();
+		if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
+			rcu_read_unlock();
 			err = -EPERM;
 			goto out;
 		}
+		rcu_read_unlock();
+
 		err = security_task_getscheduler(p);
 		if (err)
 			goto out;
@@ -2451,11 +2475,10 @@
 
 static struct dentry *proc_pident_lookup(struct inode *dir, 
 					 struct dentry *dentry,
-					 const struct pid_entry *ents,
-					 unsigned int nents)
+					 const struct pid_entry *p,
+					 const struct pid_entry *end)
 {
 	struct task_struct *task = get_proc_task(dir);
-	const struct pid_entry *p, *last;
 	struct dentry *res = ERR_PTR(-ENOENT);
 
 	if (!task)
@@ -2465,8 +2488,7 @@
 	 * Yes, it does not scale. And it should not. Don't add
 	 * new entries into /proc/<tgid>/ without very good reasons.
 	 */
-	last = &ents[nents];
-	for (p = ents; p < last; p++) {
+	for (; p < end; p++) {
 		if (p->len != dentry->d_name.len)
 			continue;
 		if (!memcmp(dentry->d_name.name, p->name, p->len)) {
@@ -2517,7 +2539,7 @@
 	if (!task)
 		return -ESRCH;
 
-	length = security_getprocattr(task,
+	length = security_getprocattr(task, PROC_I(inode)->op.lsm,
 				      (char*)file->f_path.dentry->d_name.name,
 				      &p);
 	put_task_struct(task);
@@ -2546,6 +2568,11 @@
 		rcu_read_unlock();
 		return -EACCES;
 	}
+	/* Prevent changes to overridden credentials. */
+	if (current_cred() != current_real_cred()) {
+		rcu_read_unlock();
+		return -EBUSY;
+	}
 	rcu_read_unlock();
 
 	if (count > PAGE_SIZE)
@@ -2566,7 +2593,9 @@
 	if (rv < 0)
 		goto out_free;
 
-	rv = security_setprocattr(file->f_path.dentry->d_name.name, page, count);
+	rv = security_setprocattr(PROC_I(inode)->op.lsm,
+				  file->f_path.dentry->d_name.name, page,
+				  count);
 	mutex_unlock(&current->signal->cred_guard_mutex);
 out_free:
 	kfree(page);
@@ -2580,13 +2609,53 @@
 	.llseek		= generic_file_llseek,
 };
 
+#define LSM_DIR_OPS(LSM) \
+static int proc_##LSM##_attr_dir_iterate(struct file *filp, \
+			     struct dir_context *ctx) \
+{ \
+	return proc_pident_readdir(filp, ctx, \
+				   LSM##_attr_dir_stuff, \
+				   ARRAY_SIZE(LSM##_attr_dir_stuff)); \
+} \
+\
+static const struct file_operations proc_##LSM##_attr_dir_ops = { \
+	.read		= generic_read_dir, \
+	.iterate	= proc_##LSM##_attr_dir_iterate, \
+	.llseek		= default_llseek, \
+}; \
+\
+static struct dentry *proc_##LSM##_attr_dir_lookup(struct inode *dir, \
+				struct dentry *dentry, unsigned int flags) \
+{ \
+	return proc_pident_lookup(dir, dentry, \
+				  LSM##_attr_dir_stuff, \
+				  LSM##_attr_dir_stuff + ARRAY_SIZE(LSM##_attr_dir_stuff)); \
+} \
+\
+static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \
+	.lookup		= proc_##LSM##_attr_dir_lookup, \
+	.getattr	= pid_getattr, \
+	.setattr	= proc_setattr, \
+}
+
+#ifdef CONFIG_SECURITY_SMACK
+static const struct pid_entry smack_attr_dir_stuff[] = {
+	ATTR("smack", "current",	0666),
+};
+LSM_DIR_OPS(smack);
+#endif
+
 static const struct pid_entry attr_dir_stuff[] = {
-	REG("current",    S_IRUGO|S_IWUGO, proc_pid_attr_operations),
-	REG("prev",       S_IRUGO,	   proc_pid_attr_operations),
-	REG("exec",       S_IRUGO|S_IWUGO, proc_pid_attr_operations),
-	REG("fscreate",   S_IRUGO|S_IWUGO, proc_pid_attr_operations),
-	REG("keycreate",  S_IRUGO|S_IWUGO, proc_pid_attr_operations),
-	REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
+	ATTR(NULL, "current",		0666),
+	ATTR(NULL, "prev",		0444),
+	ATTR(NULL, "exec",		0666),
+	ATTR(NULL, "fscreate",		0666),
+	ATTR(NULL, "keycreate",		0666),
+	ATTR(NULL, "sockcreate",	0666),
+#ifdef CONFIG_SECURITY_SMACK
+	DIR("smack",			0555,
+	    proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
+#endif
 };
 
 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
@@ -2605,7 +2674,8 @@
 				struct dentry *dentry, unsigned int flags)
 {
 	return proc_pident_lookup(dir, dentry,
-				  attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
+				  attr_dir_stuff,
+				  attr_dir_stuff + ARRAY_SIZE(attr_dir_stuff));
 }
 
 static const struct inode_operations proc_attr_dir_inode_operations = {
@@ -2905,6 +2975,21 @@
 }
 #endif /* CONFIG_LIVEPATCH */
 
+#ifdef CONFIG_STACKLEAK_METRICS
+static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns,
+				struct pid *pid, struct task_struct *task)
+{
+	unsigned long prev_depth = THREAD_SIZE -
+				(task->prev_lowest_stack & (THREAD_SIZE - 1));
+	unsigned long depth = THREAD_SIZE -
+				(task->lowest_stack & (THREAD_SIZE - 1));
+
+	seq_printf(m, "previous stack depth: %lu\nstack depth: %lu\n",
+							prev_depth, depth);
+	return 0;
+}
+#endif /* CONFIG_STACKLEAK_METRICS */
+
 /*
  * Thread groups
  */
@@ -2979,7 +3064,7 @@
 	ONE("oom_score",  S_IRUGO, proc_oom_score),
 	REG("oom_adj",    S_IRUGO|S_IWUSR, proc_oom_adj_operations),
 	REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
-#ifdef CONFIG_AUDITSYSCALL
+#ifdef CONFIG_AUDIT
 	REG("loginuid",   S_IWUSR|S_IRUGO, proc_loginuid_operations),
 	REG("sessionid",  S_IRUGO, proc_sessionid_operations),
 #endif
@@ -3006,6 +3091,12 @@
 #ifdef CONFIG_LIVEPATCH
 	ONE("patch_state",  S_IRUSR, proc_pid_patch_state),
 #endif
+#ifdef CONFIG_STACKLEAK_METRICS
+	ONE("stack_depth", S_IRUGO, proc_stack_depth),
+#endif
+#ifdef CONFIG_PROC_PID_ARCH_STATUS
+	ONE("arch_status", S_IRUGO, proc_pid_arch_status),
+#endif
 };
 
 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
@@ -3020,10 +3111,19 @@
 	.llseek		= generic_file_llseek,
 };
 
+struct pid *tgid_pidfd_to_pid(const struct file *file)
+{
+	if (file->f_op != &proc_tgid_base_operations)
+		return ERR_PTR(-EBADF);
+
+	return proc_pid(file_inode(file));
+}
+
 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 {
 	return proc_pident_lookup(dir, dentry,
-				  tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
+				  tgid_base_stuff,
+				  tgid_base_stuff + ARRAY_SIZE(tgid_base_stuff));
 }
 
 static const struct inode_operations proc_tgid_base_inode_operations = {
@@ -3139,7 +3239,7 @@
 	return d_splice_alias(inode, dentry);
 }
 
-struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
+struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags)
 {
 	struct task_struct *task;
 	unsigned tgid;
@@ -3364,7 +3464,7 @@
 	ONE("oom_score", S_IRUGO, proc_oom_score),
 	REG("oom_adj",   S_IRUGO|S_IWUSR, proc_oom_adj_operations),
 	REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
-#ifdef CONFIG_AUDITSYSCALL
+#ifdef CONFIG_AUDIT
 	REG("loginuid",  S_IWUSR|S_IRUGO, proc_loginuid_operations),
 	REG("sessionid",  S_IRUGO, proc_sessionid_operations),
 #endif
@@ -3384,6 +3484,9 @@
 #ifdef CONFIG_LIVEPATCH
 	ONE("patch_state",  S_IRUSR, proc_pid_patch_state),
 #endif
+#ifdef CONFIG_PROC_PID_ARCH_STATUS
+	ONE("arch_status", S_IRUGO, proc_pid_arch_status),
+#endif
 };
 
 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
@@ -3395,7 +3498,8 @@
 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 {
 	return proc_pident_lookup(dir, dentry,
-				  tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
+				  tid_base_stuff,
+				  tid_base_stuff + ARRAY_SIZE(tid_base_stuff));
 }
 
 static const struct file_operations proc_tid_base_operations = {