On Tue, 2008-06-03 at 18:41 +0100, Al Viro wrote: > On Wed, Jun 04, 2008 at 01:28:23AM +0800, Ian Kent wrote: > > > > On Tue, 2008-06-03 at 17:50 +0100, Al Viro wrote: > > > On Tue, Jun 03, 2008 at 05:41:03PM +0100, Al Viro wrote: > > > > > > > >From my reading of that code looks like it's been rmdir'ed. And no, I > > > > don't understand what the hell is that code trying to do. > > > > > > > > Ian, could you describe the race you are talking about? > > > > > > BTW, this stuff is definitely broken regardless of mount - if something > > > had the directory in question opened before that rmdir and we'd hit > > > your lookup_unhashed while another CPU had been in the middle of > > > getdents(2) on that opened descriptor, we'll get > > > > > > vfs_readdir() grabs i_mutex > > > vfs_readdir() checks that it's dead > > > autofs4_lookup_unhashed() calls iput() > > > > Can this really happen, since autofs4_lookup_unhashed() is only called > > with the i_mutex held. > > i_mutex on a different inode (obviously - it frees the inode in question, > so if caller held i_mutex on it, you would be in trouble every time you > hit that codepath). OK, I'll need to look at vfs_readdir(). I thought vfs_readdir() would take the containing directory mutex as does ->lookup(). -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
