---

yaml
---
r: 42887
b: refs/heads/master
c: d18de5a
h: refs/heads/master
i:
  42885: 177a73f
  42883: 1dfd337
  42879: 4862dfc
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1c69d921ed9cc6593ad4f60c0f9951cb0d62b0b4
+refs/heads/master: d18de5a2721f84ffd6a5d637915746ed47becc1c

trunk/fs/pipe.c

@@ -830,7 +830,14 @@ void free_pipe_info(struct inode *inode)
 static struct vfsmount *pipe_mnt __read_mostly;
 static int pipefs_delete_dentry(struct dentry *dentry)
 {
-	return 1;
+	/*
+	 * At creation time, we pretended this dentry was hashed
+	 * (by clearing DCACHE_UNHASHED bit in d_flags)
+	 * At delete time, we restore the truth : not hashed.
+	 * (so that dput() can proceed correctly)
+	 */
+	dentry->d_flags |= DCACHE_UNHASHED;
+	return 0;
 }
 
 static struct dentry_operations pipefs_dentry_operations = {
@@ -891,17 +898,22 @@ struct file *create_write_pipe(void)
 	if (!inode)
 		goto err_file;
 
-	sprintf(name, "[%lu]", inode->i_ino);
+	this.len = sprintf(name, "[%lu]", inode->i_ino);
 	this.name = name;
-	this.len = strlen(name);
-	this.hash = inode->i_ino; /* will go */
+	this.hash = 0;
 	err = -ENOMEM;
 	dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &this);
 	if (!dentry)
 		goto err_inode;
 
 	dentry->d_op = &pipefs_dentry_operations;
-	d_add(dentry, inode);
+	/*
+	 * We dont want to publish this dentry into global dentry hash table.
+	 * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
+	 * This permits a working /proc/$pid/fd/XXX on pipes
+	 */
+	dentry->d_flags &= ~DCACHE_UNHASHED;
+	d_instantiate(dentry, inode);
 	f->f_vfsmnt = mntget(pipe_mnt);
 	f->f_dentry = dentry;
 	f->f_mapping = inode->i_mapping;