On Friday 28 October 2005 22:43, john stultz wrote: > On Fri, 2005-10-28 at 22:27 +0200, Claudio Scordino wrote: > > > > We have a dual-core AMD64 with the new kernel 2.6.14 and the > > > > timer goes backward... > > > > > > > > > > > > CONFIGURATION: > > > > > > > > Kernel: 2.6.14 > > > > Distribution: Gentoo Linux 2005.0 > > > > Processor: Athlon 64 x2 4200+ (dual core) > > > > Motherboard: Abit KN8 > > > > Memory: 1GB PC3200 > > > > > > > > > > > > PROBLEM: > > > > > > > > gettimeofday goes backward and returns values that are not monotonic, > > > > giving values that are smaller than values returned before. > > > > > > > > The system has been tested with timer as PIT, PIT/TSC and PM and the > > > > problem occurs with all the configurations. > > > > > > > > Here is the config file that we used for the PM configuration. > > > > > > > > Any suggestion ? > > > > > > Booting w/ idle=poll tends to work around this issue. You might check > > > with your motherboard vendor for an updated BIOS that supports HPET or > > > the ACPI PM timer. > > > > We already updated the BIOS with the latest version. > > > > Also the booting command idle=poll doesn't work. > > Hmm. Not sure then. Is this a new regression on the same hardware? Yes, we tried with idle=poll and the problem occurred again. > > Also, how are you measuring time going backwards? With a simple C program that calls gettimeofday and sees if the new value is less than the old one. > > Would you mind filing a bug (http://bugzilla.kernel.org )on this and > attaching your config and dmesg there? Sure. Thanks, Claudio -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
