Latest working kernel version: 2.6.25.6 Earliest failing kernel version: 2.6.26-rc6 or less Distribution: Bluewhite64 (64 bits Slackware) Hardware Environment: Athlon 64 X2, 64 bits Software Environment: Dynticks, hrtimers activated in config Problem Description: It may very well be only a trace or a warning on something that never worked, but since 2.6.26 I got the following warnings in dmesg: Clockevents: could not switch to one-shot mode: lapic is not functional. Could not switch to high resolution mode on CPU 0 Clockevents: could not switch to one-shot mode: lapic is not functional. Could not switch to high resolution mode on CPU 1 followed by: Clockevents: could not switch to one-shot mode:<6>Clockevents: could not switch to one-shot mode: lapic is not functional. Could not switch to high resolution mode on CPU 0 lapic is not functional. Could not switch to high resolution mode on CPU 1 These logs were not present with 2.6.25. They seem to indicate that lapic code is not working anymore in 2.6.26. I do not see any problem otherwise in using the kernel. I append full 2.6.25 and 2.6.26 dmesg logs for analysis. Steps to reproduce: Maybe this is platform specific. I can do test and patch if necessary.
Created attachment 16567 [details] 2.6.25.6 dmesg log Lapic seems functionnal, as well as hrtimers on this version
Created attachment 16568 [details] 2.6.26-rc6 dmesg log, with the lapic error
btw, sorry, couldn't see that before because I was blocked by hardware reset sata_uli bug until yersterday and couldn't boot any 2.6.26 kernel
Command line differs. the 2.6.26 one has: nmi_watchdog=1 nmi_watchdog=1 disables the local apic timers and therefor highres/nohz Try to use nmi_watchdog=2 instead. Thanks, tglx