On Tue, Jul 25 2006, gmu 2k6 wrote:
> On 7/25/06, Jens Axboe <axboe@xxxxxxx> wrote:
> >On Tue, Jul 25 2006, gmu 2k6 wrote:
> >> On 7/25/06, Jens Axboe <axboe@xxxxxxx> wrote:
> >> >On Mon, Jul 24 2006, gmu 2k6 wrote:
> >> >> the problem I have with hangs is related to changes in CFQ and that
> >> >> CFQ is now the default. 2.6.17-git12 had the problem but booting
> >> >> it with elevator=deadline fixes the hang.
> >> >>
> >> >> symptoms encountered during git-bisecting between v2.6.17 and
> >> >v2.6.18-rc1:
> >> >> A hang while starting network services
> >> >> B hang while trying to login
> >> >> 1 on remote console [not SSH] it hang after typing <uid><CR>
> >> >> 1 via OpenSSH it hang after typing <pwd><CR> when doing slogin
> >> >root@<IP>
> >> >>
> >> >> A is the problem I got in the first place and this seems to be the
> >> >> case since 2.6.17-git11 definitely although git-bisect pointed me at
> >> >> the following
> >> >> changeset which is included since 2.6.17-git12:
> >> >>
> >> >> caaa5f9f0a75d1dc5e812e69afdbb8720e077fd3
> >> >> by Jens Axboe
> >> >> titled "[PATCH] cfq-iosched: many performance fixes"
> >> >>
> >> >> strange enough it also hangs with 2.6.17-git11 which did not include
> >that
> >> >> one changeset yet.
> >> >
> >> >So perhaps your bisect isn't 100% trust worthy? Can you do a manual
> >> >-gitX bisect to see which 2.6.17-gitX introduced the problem?
> >> >
> >> >Also please put a serial console or similar on the machine, so you can
> >> >log + store the sysrq+t output.
> >>
> >> well I didn't say that caa....fd3 is the exact change which broke it,
> >> just that it's related to 1) CFQ changes and 2) CFQ being the default
> >> now.
> >> I have a Remote Serial Console via HP's integrated Lights-Out Java
> >> Applet but am not sure how to enable serial console via kernel boot
> >> params (will try to find out).
> >> I will first try to find the 2.6.17-git* revision working before
> >> bisecting it against -git11 or git12.
> >
> >Thanks, would be much appreciated to try and narrow it down to a
> >specific fix.
> >
> >Are you seeing the hang on cciss?
>
> I'm not sure it is in the cciss driver, but the SmartArray is driven by
> cciss.
> starting git<11 boot tests in a minute now.
Ok, thanks for confirming it's cciss. The bug is likely an interaction
between cciss and cfq I think, so it would be very useful if you can pin
point which of the cfq patches make it stall.