On Sat, Jun 22, 2013 at 12:16:46PM -0700, Jesse Barnes wrote: > On Fri, 21 Jun 2013 23:58:08 -0700 > Guenter Roeck <linux at roeck-us.net> wrote: > > > Hi all, > > > > after upgrading one of my servers to 3.8, then 3.9.7 and 3.10-rc6, I started to > > see lots of "Timed out waiting for forcewake old ack to clear" error messages, > > including hang-ups especially if the system was highly loaded. With 3.5.24 > > everything was fine. > > > > After backing out commit 36ec8f877 (drm/i915: unconditionally use mt forcewake > > on hsw/ivb), everything is back to normal. The log message is still there, but > > only once during boot, and the system runs stable. > > > > CPU is "Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz", mainboard is Supermicro > > C7H61, BIOS version 2.00 dated 11/02/2012. Configuration file is whatever > > comes with Ubuntu; I'll be happy to provide a copy if anyone thinks it might > > help. > > > > Any idea what else I can do besides using a special kernel with the backed out > > commit ? Is it possible that others have the same problem ? > > Ouch, so a BIOS that uses the other forcewake mechanism seems to have > escaped. Is there a newer one available for your system? I'm hoping > it'll fix the issue, otherwise we may have to introduce both methods > for IVB again... > I installed the latest BIOS version (2.00b), but it did not fix the problem. Is there some info (such as an Intel document describing what needs to be done) which I could pass on to Supermicro ? I think it would be helpful if the condition was detected and reported, if that is possible. I spent two days so far tracking this down. It would be nice if others would not have to go through the same experience. Thanks, Guenter
