- fs-nameic-call-to-file_permission-under-a-spinlock-in-do_lookup_path.patch removed from -mm tree

[akpm@xxxxxxxx]

The patch titled

     fs/namei.c: Call to file_permission() under a spinlock in do_lookup_path()

has been  the -mm tree.  Its filename is

     fs-nameic-call-to-file_permission-under-a-spinlock-in-do_lookup_path.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
Subject: fs/namei.c: Call to file_permission() under a spinlock in do_lookup_path()
From: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>


We're presently running lock_kernel() under fs_lock via nfs's ->permission
handler.  That's a ranking bug and sometimes a sleep-in-spinlock bug.  This
problem was introduced in the openat() patchset.

We should not need to hold the current->fs->lock for a codepath that doesn't
use current->fs.

[vsu@xxxxxxxxxxx: fix error path]
Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxx>
Signed-off-by: Sergey Vlasov <vsu@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---

 fs/namei.c |   19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff -puN fs/namei.c~fs-nameic-call-to-file_permission-under-a-spinlock-in-do_lookup_path fs/namei.c
--- devel/fs/namei.c~fs-nameic-call-to-file_permission-under-a-spinlock-in-do_lookup_path	2006-06-04 02:51:15.000000000 -0700
+++ devel-akpm/fs/namei.c	2006-06-04 02:51:15.000000000 -0700
@@ -1080,8 +1080,8 @@ static int fastcall do_path_lookup(int d
 	nd->flags = flags;
 	nd->depth = 0;
 
-	read_lock(&current->fs->lock);
 	if (*name=='/') {
+		read_lock(&current->fs->lock);
 		if (current->fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
 			nd->mnt = mntget(current->fs->altrootmnt);
 			nd->dentry = dget(current->fs->altroot);
@@ -1092,33 +1092,35 @@ static int fastcall do_path_lookup(int d
 		}
 		nd->mnt = mntget(current->fs->rootmnt);
 		nd->dentry = dget(current->fs->root);
+		read_unlock(&current->fs->lock);
 	} else if (dfd == AT_FDCWD) {
+		read_lock(&current->fs->lock);
 		nd->mnt = mntget(current->fs->pwdmnt);
 		nd->dentry = dget(current->fs->pwd);
+		read_unlock(&current->fs->lock);
 	} else {
 		struct dentry *dentry;
 
 		file = fget_light(dfd, &fput_needed);
 		retval = -EBADF;
 		if (!file)
-			goto unlock_fail;
+			goto out_fail;
 
 		dentry = file->f_dentry;
 
 		retval = -ENOTDIR;
 		if (!S_ISDIR(dentry->d_inode->i_mode))
-			goto fput_unlock_fail;
+			goto fput_fail;
 
 		retval = file_permission(file, MAY_EXEC);
 		if (retval)
-			goto fput_unlock_fail;
+			goto fput_fail;
 
 		nd->mnt = mntget(file->f_vfsmnt);
 		nd->dentry = dget(dentry);
 
 		fput_light(file, fput_needed);
 	}
-	read_unlock(&current->fs->lock);
 	current->total_link_count = 0;
 	retval = link_path_walk(name, nd);
 out:
@@ -1127,13 +1129,12 @@ out:
 				nd->dentry->d_inode))
 		audit_inode(name, nd->dentry->d_inode, flags);
 	}
+out_fail:
 	return retval;
 
-fput_unlock_fail:
+fput_fail:
 	fput_light(file, fput_needed);
-unlock_fail:
-	read_unlock(&current->fs->lock);
-	return retval;
+	goto out_fail;
 }
 
 int fastcall path_lookup(const char *name, unsigned int flags,
_

Patches currently in -mm which might be from Trond.Myklebust@xxxxxxxxxx are

git-nfs.patch

-
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