diff --git a/fs/proc/cpuinfo.c b/fs/proc/cpuinfo.c
index c1dea9b..d0989a4 100644
--- a/fs/proc/cpuinfo.c
+++ b/fs/proc/cpuinfo.c
@@ -17,6 +17,7 @@ static int cpuinfo_open(struct inode *inode, struct file *file)
 }
 
 static const struct proc_ops cpuinfo_proc_ops = {
+	.proc_flags	= PROC_ENTRY_PERMANENT,
 	.proc_open	= cpuinfo_open,
 	.proc_read	= seq_read,
 	.proc_lseek	= seq_lseek,
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 3faed94..4ed6dab 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -531,6 +531,12 @@ struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
 	return p;
 }
 
+static inline void pde_set_flags(struct proc_dir_entry *pde)
+{
+	if (pde->proc_ops->proc_flags & PROC_ENTRY_PERMANENT)
+		pde->flags |= PROC_ENTRY_PERMANENT;
+}
+
 struct proc_dir_entry *proc_create_data(const char *name, umode_t mode,
 		struct proc_dir_entry *parent,
 		const struct proc_ops *proc_ops, void *data)
@@ -541,6 +547,7 @@ struct proc_dir_entry *proc_create_data(const char *name, umode_t mode,
 	if (!p)
 		return NULL;
 	p->proc_ops = proc_ops;
+	pde_set_flags(p);
 	return proc_register(parent, p);
 }
 EXPORT_SYMBOL(proc_create_data);
@@ -572,6 +579,7 @@ static int proc_seq_release(struct inode *inode, struct file *file)
 }
 
 static const struct proc_ops proc_seq_ops = {
+	/* not permanent -- can call into arbitrary seq_operations */
 	.proc_open	= proc_seq_open,
 	.proc_read	= seq_read,
 	.proc_lseek	= seq_lseek,
@@ -602,6 +610,7 @@ static int proc_single_open(struct inode *inode, struct file *file)
 }
 
 static const struct proc_ops proc_single_ops = {
+	/* not permanent -- can call into arbitrary ->single_show */
 	.proc_open	= proc_single_open,
 	.proc_read	= seq_read,
 	.proc_lseek	= seq_lseek,
@@ -662,9 +671,13 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 
 	de = pde_subdir_find(parent, fn, len);
 	if (de) {
-		rb_erase(&de->subdir_node, &parent->subdir);
-		if (S_ISDIR(de->mode)) {
-			parent->nlink--;
+		if (unlikely(pde_is_permanent(de))) {
+			WARN(1, "removing permanent /proc entry '%s'", de->name);
+			de = NULL;
+		} else {
+			rb_erase(&de->subdir_node, &parent->subdir);
+			if (S_ISDIR(de->mode))
+				parent->nlink--;
 		}
 	}
 	write_unlock(&proc_subdir_lock);
@@ -700,12 +713,24 @@ int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
 		write_unlock(&proc_subdir_lock);
 		return -ENOENT;
 	}
+	if (unlikely(pde_is_permanent(root))) {
+		write_unlock(&proc_subdir_lock);
+		WARN(1, "removing permanent /proc entry '%s/%s'",
+			root->parent->name, root->name);
+		return -EINVAL;
+	}
 	rb_erase(&root->subdir_node, &parent->subdir);
 
 	de = root;
 	while (1) {
 		next = pde_subdir_first(de);
 		if (next) {
+			if (unlikely(pde_is_permanent(root))) {
+				write_unlock(&proc_subdir_lock);
+				WARN(1, "removing permanent /proc entry '%s/%s'",
+					next->parent->name, next->name);
+				return -EINVAL;
+			}
 			rb_erase(&next->subdir_node, &de->subdir);
 			de = next;
 			continue;
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 05d31c4..fb4cace 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -259,115 +259,193 @@ void proc_entry_rundown(struct proc_dir_entry *de)
 	spin_unlock(&de->pde_unload_lock);
 }
 
+static loff_t pde_lseek(struct proc_dir_entry *pde, struct file *file, loff_t offset, int whence)
+{
+	typeof_member(struct proc_ops, proc_lseek) lseek;
+
+	lseek = pde->proc_ops->proc_lseek;
+	if (!lseek)
+		lseek = default_llseek;
+	return lseek(file, offset, whence);
+}
+
 static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	loff_t rv = -EINVAL;
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_lseek) lseek;
 
-		lseek = pde->proc_ops->proc_lseek;
-		if (!lseek)
-			lseek = default_llseek;
-		rv = lseek(file, offset, whence);
+	if (pde_is_permanent(pde)) {
+		return pde_lseek(pde, file, offset, whence);
+	} else if (use_pde(pde)) {
+		rv = pde_lseek(pde, file, offset, whence);
 		unuse_pde(pde);
 	}
 	return rv;
 }
 
+static ssize_t pde_read(struct proc_dir_entry *pde, struct file *file, char __user *buf, size_t count, loff_t *ppos)
+{
+	typeof_member(struct proc_ops, proc_read) read;
+
+	read = pde->proc_ops->proc_read;
+	if (read)
+		return read(file, buf, count, ppos);
+	return -EIO;
+}
+
 static ssize_t proc_reg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	ssize_t rv = -EIO;
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_read) read;
 
-		read = pde->proc_ops->proc_read;
-		if (read)
-			rv = read(file, buf, count, ppos);
+	if (pde_is_permanent(pde)) {
+		return pde_read(pde, file, buf, count, ppos);
+	} else if (use_pde(pde)) {
+		rv = pde_read(pde, file, buf, count, ppos);
 		unuse_pde(pde);
 	}
 	return rv;
 }
 
+static ssize_t pde_write(struct proc_dir_entry *pde, struct file *file, const char __user *buf, size_t count, loff_t *ppos)
+{
+	typeof_member(struct proc_ops, proc_write) write;
+
+	write = pde->proc_ops->proc_write;
+	if (write)
+		return write(file, buf, count, ppos);
+	return -EIO;
+}
+
 static ssize_t proc_reg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	ssize_t rv = -EIO;
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_write) write;
 
-		write = pde->proc_ops->proc_write;
-		if (write)
-			rv = write(file, buf, count, ppos);
+	if (pde_is_permanent(pde)) {
+		return pde_write(pde, file, buf, count, ppos);
+	} else if (use_pde(pde)) {
+		rv = pde_write(pde, file, buf, count, ppos);
 		unuse_pde(pde);
 	}
 	return rv;
 }
 
+static __poll_t pde_poll(struct proc_dir_entry *pde, struct file *file, struct poll_table_struct *pts)
+{
+	typeof_member(struct proc_ops, proc_poll) poll;
+
+	poll = pde->proc_ops->proc_poll;
+	if (poll)
+		return poll(file, pts);
+	return DEFAULT_POLLMASK;
+}
+
 static __poll_t proc_reg_poll(struct file *file, struct poll_table_struct *pts)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	__poll_t rv = DEFAULT_POLLMASK;
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_poll) poll;
 
-		poll = pde->proc_ops->proc_poll;
-		if (poll)
-			rv = poll(file, pts);
+	if (pde_is_permanent(pde)) {
+		return pde_poll(pde, file, pts);
+	} else if (use_pde(pde)) {
+		rv = pde_poll(pde, file, pts);
 		unuse_pde(pde);
 	}
 	return rv;
 }
 
+static long pde_ioctl(struct proc_dir_entry *pde, struct file *file, unsigned int cmd, unsigned long arg)
+{
+	typeof_member(struct proc_ops, proc_ioctl) ioctl;
+
+	ioctl = pde->proc_ops->proc_ioctl;
+	if (ioctl)
+		return ioctl(file, cmd, arg);
+	return -ENOTTY;
+}
+
 static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	long rv = -ENOTTY;
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_ioctl) ioctl;
 
-		ioctl = pde->proc_ops->proc_ioctl;
-		if (ioctl)
-			rv = ioctl(file, cmd, arg);
+	if (pde_is_permanent(pde)) {
+		return pde_ioctl(pde, file, cmd, arg);
+	} else if (use_pde(pde)) {
+		rv = pde_ioctl(pde, file, cmd, arg);
 		unuse_pde(pde);
 	}
 	return rv;
 }
 
 #ifdef CONFIG_COMPAT
+static long pde_compat_ioctl(struct proc_dir_entry *pde, struct file *file, unsigned int cmd, unsigned long arg)
+{
+	typeof_member(struct proc_ops, proc_compat_ioctl) compat_ioctl;
+
+	compat_ioctl = pde->proc_ops->proc_compat_ioctl;
+	if (compat_ioctl)
+		return compat_ioctl(file, cmd, arg);
+	return -ENOTTY;
+}
+
 static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	long rv = -ENOTTY;
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_compat_ioctl) compat_ioctl;
-
-		compat_ioctl = pde->proc_ops->proc_compat_ioctl;
-		if (compat_ioctl)
-			rv = compat_ioctl(file, cmd, arg);
+	if (pde_is_permanent(pde)) {
+		return pde_compat_ioctl(pde, file, cmd, arg);
+	} else if (use_pde(pde)) {
+		rv = pde_compat_ioctl(pde, file, cmd, arg);
 		unuse_pde(pde);
 	}
 	return rv;
 }
 #endif
 
+static int pde_mmap(struct proc_dir_entry *pde, struct file *file, struct vm_area_struct *vma)
+{
+	typeof_member(struct proc_ops, proc_mmap) mmap;
+
+	mmap = pde->proc_ops->proc_mmap;
+	if (mmap)
+		return mmap(file, vma);
+	return -EIO;
+}
+
 static int proc_reg_mmap(struct file *file, struct vm_area_struct *vma)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	int rv = -EIO;
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_mmap) mmap;
 
-		mmap = pde->proc_ops->proc_mmap;
-		if (mmap)
-			rv = mmap(file, vma);
+	if (pde_is_permanent(pde)) {
+		return pde_mmap(pde, file, vma);
+	} else if (use_pde(pde)) {
+		rv = pde_mmap(pde, file, vma);
 		unuse_pde(pde);
 	}
 	return rv;
 }
 
 static unsigned long
+pde_get_unmapped_area(struct proc_dir_entry *pde, struct file *file, unsigned long orig_addr,
+			   unsigned long len, unsigned long pgoff,
+			   unsigned long flags)
+{
+	typeof_member(struct proc_ops, proc_get_unmapped_area) get_area;
+
+	get_area = pde->proc_ops->proc_get_unmapped_area;
+#ifdef CONFIG_MMU
+	if (!get_area)
+		get_area = current->mm->get_unmapped_area;
+#endif
+	if (get_area)
+		return get_area(file, orig_addr, len, pgoff, flags);
+	return orig_addr;
+}
+
+static unsigned long
 proc_reg_get_unmapped_area(struct file *file, unsigned long orig_addr,
 			   unsigned long len, unsigned long pgoff,
 			   unsigned long flags)
@@ -375,19 +453,10 @@ proc_reg_get_unmapped_area(struct file *file, unsigned long orig_addr,
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	unsigned long rv = -EIO;
 
-	if (use_pde(pde)) {
-		typeof_member(struct proc_ops, proc_get_unmapped_area) get_area;
-
-		get_area = pde->proc_ops->proc_get_unmapped_area;
-#ifdef CONFIG_MMU
-		if (!get_area)
-			get_area = current->mm->get_unmapped_area;
-#endif
-
-		if (get_area)
-			rv = get_area(file, orig_addr, len, pgoff, flags);
-		else
-			rv = orig_addr;
+	if (pde_is_permanent(pde)) {
+		return pde_get_unmapped_area(pde, file, orig_addr, len, pgoff, flags);
+	} else if (use_pde(pde)) {
+		rv = pde_get_unmapped_area(pde, file, orig_addr, len, pgoff, flags);
 		unuse_pde(pde);
 	}
 	return rv;
@@ -401,6 +470,13 @@ static int proc_reg_open(struct inode *inode, struct file *file)
 	typeof_member(struct proc_ops, proc_release) release;
 	struct pde_opener *pdeo;
 
+	if (pde_is_permanent(pde)) {
+		open = pde->proc_ops->proc_open;
+		if (open)
+			rv = open(inode, file);
+		return rv;
+	}
+
 	/*
 	 * Ensure that
 	 * 1) PDE's ->release hook will be called no matter what
@@ -450,6 +526,17 @@ static int proc_reg_release(struct inode *inode, struct file *file)
 {
 	struct proc_dir_entry *pde = PDE(inode);
 	struct pde_opener *pdeo;
+
+	if (pde_is_permanent(pde)) {
+		typeof_member(struct proc_ops, proc_release) release;
+
+		release = pde->proc_ops->proc_release;
+		if (release) {
+			return release(inode, file);
+		}
+		return 0;
+	}
+
 	spin_lock(&pde->pde_unload_lock);
 	list_for_each_entry(pdeo, &pde->pde_openers, lh) {
 		if (pdeo->file == file) {
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 9e294f0..917cc85 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -61,6 +61,7 @@ struct proc_dir_entry {
 	struct rb_node subdir_node;
 	char *name;
 	umode_t mode;
+	u8 flags;
 	u8 namelen;
 	char inline_name[];
 } __randomize_layout;
@@ -73,6 +74,11 @@ struct proc_dir_entry {
 	0)
 #define SIZEOF_PDE_INLINE_NAME (SIZEOF_PDE - sizeof(struct proc_dir_entry))
 
+static inline bool pde_is_permanent(const struct proc_dir_entry *pde)
+{
+	return pde->flags & PROC_ENTRY_PERMANENT;
+}
+
 extern struct kmem_cache *proc_dir_entry_cache;
 void pde_free(struct proc_dir_entry *pde);
 
diff --git a/fs/proc/kmsg.c b/fs/proc/kmsg.c
index ec1b7d2..b38ad55 100644
--- a/fs/proc/kmsg.c
+++ b/fs/proc/kmsg.c
@@ -50,6 +50,7 @@ static __poll_t kmsg_poll(struct file *file, poll_table *wait)
 
 
 static const struct proc_ops kmsg_proc_ops = {
+	.proc_flags	= PROC_ENTRY_PERMANENT,
 	.proc_read	= kmsg_read,
 	.proc_poll	= kmsg_poll,
 	.proc_open	= kmsg_open,
diff --git a/fs/proc/stat.c b/fs/proc/stat.c
index 0449edf..46b3293 100644
--- a/fs/proc/stat.c
+++ b/fs/proc/stat.c
@@ -224,6 +224,7 @@ static int stat_open(struct inode *inode, struct file *file)
 }
 
 static const struct proc_ops stat_proc_ops = {
+	.proc_flags	= PROC_ENTRY_PERMANENT,
 	.proc_open	= stat_open,
 	.proc_read	= seq_read,
 	.proc_lseek	= seq_lseek,