Re: deadlocks if use htb

Chris Caputo
2009-01-15T12:08:20Z

On Thu, 15 Jan 2009, Jarek Poplawski wrote:
> On Thu, Jan 15, 2009 at 07:54:50AM +0000, Jarek Poplawski wrote:
> > On Thu, Jan 15, 2009 at 07:26:28AM +0000, Chris Caputo wrote:
> > > On Thu, 15 Jan 2009, Jarek Poplawski wrote:
> > > > On Wed, Jan 14, 2009 at 06:02:04PM +0000, Chris Caputo wrote:
> > > > ...
> > > > > That said, I would not recommend just the three for -stable unless they
> > > > > get a much wider amount of testing, on multiple platforms. I don't see
> > > > > that as likely to happen, plus Peter says they are incomplete, so maybe it
> > > > > is just best to recommend that 2.6.28 users getting crashes while using
> > > > > HTB try these specific patches at first, and then the rest of the patches
> > > > > if they do not work.
> > ...
> > > I hope you can forgive me, but since I have something that works on a
> > > production machine, I am not in a position in which I can test this.
> >
> > So, IOW, you don't recommend Peter's patches but prefere to use them,
> > and recommend my patches, but you are afraid of using them...
>
> Sorry, Chris! It looks like I misunderstood, and you recomend Peter's
> patches yet. (But I guess there are users relying on official kernel
> versions.)
>
> I hope you can forgive me,

:-) No worries.

Just to be clear, by "these specific patches at first", I mean the
"hrtimer: removing all ur callback modes" ones:

ca109491f612aab5c8152207631c0444f63da97f
37810659ea7d9572c5ac284ade272f806ef8f788
a0a99b227da57f81319dd239bc4de811b0f530ec

By "rest of the patches", I mean the above plus the others created by
Peter for hrtimers. Full list:

ca109491f612aab5c8152207631c0444f63da97f
37810659ea7d9572c5ac284ade272f806ef8f788
a0a99b227da57f81319dd239bc4de811b0f530ec
b2e3c0adec918ea22b6c9d7c76193dd3aaba9bd4
8bdec955b0da2ffbd10eb9b200651dd1f9e366f2
d5fd43c4ae04523e1dcd7794f9c511b289851350
731a55ba0f17064f85903b7bf8e24849ec6cfa20
a6037b61c2f5fc99c57c15b26d7cfa58bbb34008
e3f1d883740b09e5116d4d4e30a6a6987264a83c
82c5b7b527ccc4b5d3cf832437e842f9d2920a79
6e5c172cf7ca1ab878cc6a6a4c1d52fef60f3ee0

The first 3 git patches listed above are working for me so far, so I have
not had a need to try the others.

On Thu, Jan 15, 2009 at 11:57:13AM +0200, Denys Fedoryschenko wrote:
> I didn't notice a bug, just because all that time i was using it without
> hrtimers (because of nmi_watchdog).

nmi_watchdog 1 or 2? I'm running with 2 which I've read does not disable
hrtimers, right?

I mention it because my original HTB/hrtimers-related crash on .28 was
without nmi_watchdog altogether. I added both "nmi_watchdog=panic,2" and
Peter's first 3 patches (ca1, 378, a0a) at the same time, to produce an
apparently stable system.

I wish I had a repro scenario in a non-production environment, so I could
help out further with this. If I did, I would test without nmi_watchdog
while trying just 2.6.28 and Jarek's #4 patch.

Chris