Re: Oops with tmpfs on both 2.4.22 & 2.6.0-test11

[Oleg Drokin <green@linuxhacker.ru>]

Hello!

William Lee Irwin III <wli@holomorphy.com> wrote:

WLII> Could you try 2.6 with the following patch and send in the resulting
WLII> oops/BUG? Please turn on kallsyms for the run.
WLII>                         while (n && p != &file->f_dentry->d_subdirs) {
WLII>                                 struct dentry *next;
WLII>                                 next = list_entry(p, struct dentry, d_child);
WLII> +                               BUG_ON(!next);
WLII>                                 if (!d_unhashed(next) && next->d_inode)
WLII>                                         n--;
WLII>                                 p = p->next;
WLII>                         }

This loop is never run since n is 0

WLII> +                       BUG_ON(!cursor);
WLII>                         list_del(&cursor->d_child);
WLII>                         list_add_tail(&cursor->d_child, p);

The problem seems to be because &cursor->d_child is equal to p,
so on list_del we zero p->prev, and then assign to p->prev->next in
list_add_tail.
&cursor->d_child is equal to p probably because we just created it this
way in dcache_dir_open()

Bye,
    Oleg