From: Jonathan Sambrook (jonathan.sambrook_at_dsvr.co.uk)
Date: Fri 12 Dec 2003 - 20:10:09 GMT
At 01:09 on Fri 12/12/03, herbert_at_13thfloor.at masquerading as 'Herbert Poetzl' wrote:
> On Thu, Dec 11, 2003 at 05:23:21PM +0000, Jonathan Sambrook wrote:
> > At 16:07 on Fri 05/12/03, herbert_at_13thfloor.at masquerading as 'Herbert Poetzl' wrote:
> > >
> > > - critical bugfix in tcp(6)_get_info()
> > > - critical bugfix SMP deadlock, dyn.
> >
> > Unfortunately not quite there yet. There appear to have been two
> > unrelated issues since I've still been getting crashes, but at a much slower
> > rate on 2.4.23-vs1.2{0,1}. They occur more quickly with my other patches
> > in place, but since they're timing susceptible, that doesn't say much.
> >
> > The fix I have is to replace the uts_sem write locks in vcontext.c's
> > vx_assign_info and vx_release_info with a spinlock. They aren't related
> > to the uts_name in anyway, so were only freeloading anyhow :)
> >
> > See: http://jonathan.dsvr.co.uk/kernel/index.html#vsbug
> >
> > Opinion(s) please.
>
> Hi Jonathan!
>
> the url for the patch is wrong (vserver is missing)
Oops. Corrected - FWIW :)
>
> I totally agree that uts_sem isn't the apropriate
> to use in this place(s), but I don't see how this
> could cause a deadlock/panic as there is nothing
> to lock/panic if the rw sem is held for write ...
Neither do I, but the call from exit.c seems to lock.
> please correct me if you see any crash/lock condition
> there ...
My machines running with these write locks replaced by a spinlock have
been up for over two days now, instead of less than a minute. No other
changes!
> what would be interesting is, how does vs1.3.0
> behave in your tests, as it replaced the allocation
> scheme completely (so no assign/alloc and no rw
> uts_sem to fix ;)
Yes. Will examine on Monday. But need to go live on some reall machines
soon too...
Cheers,
Jonathan
>
> TIA,
> Herbert
>
> > Jonathan
> _______________________________________________
> Vserver mailing list
> Vserver_at_list.linux-vserver.org
> http://list.linux-vserver.org/mailman/listinfo/vserver
--
Jonathan Sambrook
Software Developer
Designer Servers