Re: Linux 2.6.38-rc5

[Eric Dumazet <eric.dumazet@gmail.com>]

Le mercredi 16 février 2011 à 16:39 +0000, Al Viro a écrit :
> On Wed, Feb 16, 2011 at 08:33:32AM -0800, Linus Torvalds wrote:
> > Does it make tons of conceptual sense to pass in 'inode' to
> > do_follow_link? No, it's clearly redundant information, which is the
> > whole point of the BUG_ON(). But it does allow that extra shared
> > sanity test, and we _could_ also then do
> > 
> >   -       if (!IS_ERR(cookie) && path->dentry->d_inode->i_op->put_link)
> >   -               path->dentry->d_inode->i_op->put_link(path->dentry,
> > nd, cookie);
> >   +       if (!IS_ERR(cookie) && inode->i_op->put_link)
> >   +               inode->i_op->put_link(path->dentry, nd, cookie);
> > 
> > since we've verified that 'inode' is 'path->dentry->d_inode', and all
> > of those should be stable over all the calls (in the non-RCU case,
> > which we are in).
> > 
> > I dunno. I don't care _deeply_, but I do have to say that I much liked
> > how you moved the
> > 
> >     if (nameidata_dentry_drop_rcu_maybe(nd, path->dentry))
> >       ..
> > 
> > into do_follow_link(). I think it made it clearer that do_follow_link
> > (and __do_follow_link()) aren't done with RCU.
> 
> OK, I can live with that.  Consider me convinced, let's go with your variant.
> Speaking of ugliness: Nick, why the _fuck_ have you reverted non-create case
> in do_filp_open() to do_path_lookup()?

I tested both (Linus/Al) versions, please feel free to add

Tested-by: Eric Dumazet <eric.dumazet@gmail.com>