Old LOR between devfs & devfsmount resurfacing?

[Kostik Belousov]

On Wed, Feb 13, 2008 at 11:38:27AM -0500, John Baldwin wrote:
> On Thursday 07 February 2008 09:11:46 am Attilio Rao wrote:
> > 2008/2/7, Kostik Belousov <kostikbel at gmail.com>:
> > > On Thu, Feb 07, 2008 at 01:21:09PM +0100, Attilio Rao wrote:
> > > > 2008/2/7, Kostik Belousov <kostikbel at gmail.com>:
> > > > > This LOR shall not be ignored globally. When real, it caused the 
> easily
> > > > >  reproducable lockup of the machine.
> > > > >
> > > > >  It would be better to introduce some lockmgr flag to ignore _this_ 
> locking.
> > > >
> > > > flag to pass where?
> > > To the lockmgr itself at the point of aquisition, like
> > >        lockmgr(&lk, LK_EXCLUSIVE | LK_INTERLOCK | LK_NOWARN, 
> &interlk, ...);
> > 
> > No, I really want a general WITNESS support for this (as I also think
> > that having something more fine grained than BLESSING will break all
> > concerns jhb and me are considering now).
> > A simple way to do it would mean hard-coding file and line in a
> > witness table. While file is ok, line makes trouble so we should find
> > an alternative way to do this. Otherwise we can consider skiping
> > checks for a whole function, this should be not so difficult to
> > achive.
> > 
> > I need to think more about this.
> 
> I think allowing a flag is fine, just as you can specify MTX_QUIET to quiet 
> KTR logs in specific mtx_lock() instances.  You would specify LK_NOWITNESS or 
> some such and have it not do a witness_checkorder() in that case.

Exactly what I wanted.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 195 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-current/attachments/20080213/eec81ca4/attachment-0001.pgp