Hi Jörg
On Tue, 30 Jun 2015 16:58:13 +0200
Jörg Otte <[email protected]> wrote:
> > Regarding the system hang issue, it looks like the problem is caused by the
> > list_del().
> > According to the list.h, this macro puts the entry into invalid state and
> > it causes the device hang in the l2cap_core.c
> >
> > /**
> > * list_del - deletes entry from list.
> > * @entry: the element to delete from the list.
> > * Note: list_empty() on entry does not return true after this, the
> > entry is
> > * in an undefined state.
> > */
> >
> > So, one way to fix this issue is using the list_del_init() instead.
> >
> > Can you try this patch to see if it resolve the issue? No need to revert
> > any patch.
> > I ran a quick test with a different scenarios and it looks good to me so
> > far.
> >
> > diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
> > index 51594fb..45fffa4 100644
> > --- a/net/bluetooth/l2cap_core.c
> > +++ b/net/bluetooth/l2cap_core.c
> > @@ -1634,7 +1634,7 @@ void l2cap_unregister_user(struct l2cap_conn *conn,
> > struct l2cap_user *user)
> > if (list_empty(&user->list))
> > goto out_unlock;
> >
> > - list_del(&user->list);
> > + list_del_init(&user->list);
> > user->remove(conn, user);
> >
> > out_unlock:
> > @@ -1648,7 +1648,7 @@ static void l2cap_unregister_all_users(struct
> > l2cap_conn *conn)
> >
> > while (!list_empty(&conn->users)) {
> > user = list_first_entry(&conn->users, struct l2cap_user,
> > list);
> > - list_del(&user->list);
> > + list_del_init(&user->list);
> > user->remove(conn, user);
> > }
> > }
> >
> > Regards,
> > Tedd Ho-Jeong An
>
> I now have both patche applied and no revert. Looks good so far.
>
> Thanks, Jörg
Thanks for testing the patch. I submitted the patch just in case.
Now, I am tossing the ball to Marcel. :)
Regards,
Tedd
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