On 2007-06-14 18:36, Attilio Rao <attilio_at_freebsd.org> wrote: >2007/6/14, Giorgos Keramidas <keramida_at_ceid.upatras.gr>: >> If I leave my laptop idle for a long period of time, it tends to lock up >> with the CPU fan spinning fast (presumambly because some part of the >> kernel tries to acquire a lock and spins constantly for it). >> >> Unfortunately, this happens when X11 is running and I can't break into >> DDB to snoop around. >> >> I did notice that if I leave a terminal running: >> >> $ while true ; do \ >> echo -n "$(date '+%Y-%m-%d %H:%M') " ; \ >> tail -1 /var/log/messages ; \ >> sleep 10 ; \ >> done >> >> this works as a 'workaround' for the hardlock. >> >> The sources of /usr/src have been updated up to: >> >> 2007.06.12.15.37.17 >> >> Any ideas how I could try to debug this? > > Recompile the kernel with DDB support (pay attention to disable > KDB_UNATTENDED), additionally add WITNESS support (paying attention to > not add WITNESS_SKIPSPIN), even if this wouldn't help in direct > analysis. > > Then, when the kernel hangs, just break into the debugger and print > out bt, show alllocks, ps. Unfortunately, I've only been able to reproduce this while X11 is running, so I can't enter the debugger. I'll see if I can reproduce this on a desktop system with a serial console, because entering ddb on a laptop running X11 without a serial port is at best tricky :) Thanks for the ddb command tips though :-)Received on Thu Jun 14 2007 - 15:03:05 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:39:12 UTC