Re: [GIT PULL] Please pull NFS client bugfixes....

From: Andi Kleen
Date: Thu Jan 07 2010 - 16:00:44 EST



> Hi Linus,
>
> Please pull from the "bugfixes" branch of the repository at
>
> git pull git://git.linux-nfs.org/projects/trondmy/nfs-2.6.git bugfixes
>
> This will update the following files through the appended changesets.

How about the mmap lock order inversion patch?

That problem is still there and hits immediately after mounting root
with a lockdep warning on any lockdep enabled NFS root kernel.

-Andi

---

NFS: don't revalidate in mmap

nfs_revalidate_mapping takes i_mutex, but mmap already has mmap_sem
hold and taking i_mutex inside mmap_sem is not allowed by the VFS.

So don't revalidate on mmap time and trust it has been already done.

Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>

---
fs/nfs/file.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

Index: linux-2.6.32-ak/fs/nfs/file.c
===================================================================
--- linux-2.6.32-ak.orig/fs/nfs/file.c
+++ linux-2.6.32-ak/fs/nfs/file.c
@@ -297,14 +297,9 @@ nfs_file_mmap(struct file * file, struct
dprintk("NFS: mmap(%s/%s)\n",
dentry->d_parent->d_name.name, dentry->d_name.name);

- /* Note: generic_file_mmap() returns ENOSYS on nommu systems
- * so we call that before revalidating the mapping
- */
status = generic_file_mmap(file, vma);
- if (!status) {
+ if (!status)
vma->vm_ops = &nfs_file_vm_ops;
- status = nfs_revalidate_mapping(inode, file->f_mapping);
- }
return status;
}



--
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/