X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=mm%2Fmemcontrol.c;h=3e8f1ad0fe9db282e43454b67b0c706bd373c46a;hb=refs%2Fheads%2Fsandbox%2Flstelmach%2Fvirgl;hp=a1a35c12635ef7ea49528c8857fae9016644cfc9;hpb=6085bc95797caa55a68bc0f7dd73e8c33e91037f;p=platform%2Fkernel%2Flinux-starfive.git

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a1a35c1..3e8f1ad 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3910,6 +3910,10 @@ static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css,
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
 
+	pr_warn_once("Cgroup memory moving (move_charge_at_immigrate) is deprecated. "
+		     "Please report your usecase to linux-mm@kvack.org if you "
+		     "depend on this functionality.\n");
+
 	if (val & ~MOVE_MASK)
 		return -EINVAL;
 
@@ -4832,6 +4836,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
 	unsigned int efd, cfd;
 	struct fd efile;
 	struct fd cfile;
+	struct dentry *cdentry;
 	const char *name;
 	char *endp;
 	int ret;
@@ -4886,6 +4891,16 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
 		goto out_put_cfile;
 
 	/*
+	 * The control file must be a regular cgroup1 file. As a regular cgroup
+	 * file can't be renamed, it's safe to access its name afterwards.
+	 */
+	cdentry = cfile.file->f_path.dentry;
+	if (cdentry->d_sb->s_type != &cgroup_fs_type || !d_is_reg(cdentry)) {
+		ret = -EINVAL;
+		goto out_put_cfile;
+	}
+
+	/*
 	 * Determine the event callbacks and set them in @event.  This used
 	 * to be done via struct cftype but cgroup core no longer knows
 	 * about these events.  The following is crude but the whole thing
@@ -4893,7 +4908,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
 	 *
 	 * DO NOT ADD NEW FILES.
 	 */
-	name = cfile.file->f_path.dentry->d_name.name;
+	name = cdentry->d_name.name;
 
 	if (!strcmp(name, "memory.usage_in_bytes")) {
 		event->register_event = mem_cgroup_usage_register_event;
@@ -4917,7 +4932,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
 	 * automatically removed on cgroup destruction but the removal is
 	 * asynchronous, so take an extra ref on @css.
 	 */
-	cfile_css = css_tryget_online_from_dir(cfile.file->f_path.dentry->d_parent,
+	cfile_css = css_tryget_online_from_dir(cdentry->d_parent,
 					       &memory_cgrp_subsys);
 	ret = -EINVAL;
 	if (IS_ERR(cfile_css))