On Wednesday, 18 of June 2008, Maciej W. Rozycki wrote: > On Wed, 18 Jun 2008, Rafael J. Wysocki wrote: > > > Here you go. Below is the relevant snippet from the yesterday's linux-next > > dmesg with the patches: > > "x86: I/O APIC: timer through 8259A second-chance" > > "x86: add C1E aware idle function" > > reverted and the appended debug patch applied. > > > > [ 0.108006] TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 > > [ 0.108006] ..MP-BIOS bug: 8254 timer not connected to IO-APIC > > [ 0.108006] ...trying to set up timer (IRQ0) through the 8259A ... <2> failed > > [ 0.108006] ...trying to set up timer as Virtual Wire IRQ...<2> works. > > > > The entire dmesg is at: http://www.sisk.pl/kernel/debug/20080616/dmesg-4.log > > Thanks -- this is very important and useful information as it shows the > exact alternative used. > > With such a configuration the "x86: I/O APIC: timer through 8259A > second-chance" patch should not matter, because the only change it > introduces is an attempt to try the same I/O APIC pin again, but with the > IRQ0 line of the master 8259A enabled. That's not a terribly unusual > configuration and nothing should get confused in the system. But it _does_ get confused, really. > Barring the unlikely possibility of the 8259A actually being wired to > INTIN2 of the I/O APIC I can see two possible explanations: > > 1. The 8259A interrupt actually escapes to the CPU somehow and is handled > as an ExtINTA interrupt. This would make the code in check_timer() > decide it has found a working configuration, while actually it has been > fooled. > > 2. There is a bug in this patch or an assumption it makes which results > in the state of some component not to be restored correctly. > Unfortunately I have no resources to test the 64-bit variation of the > code, so something may have escaped my attention. > > I'd like to find out which one is the case -- can you please reapply the > patch and send me the corresponding section of the bootstrap log? If the > system hangs before you can retrieve the log, please just place: Here you go: [ 0.108006] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 [ 0.108006] ..MP-BIOS bug: 8254 timer not connected to IO-APIC [ 0.108006] ...trying to set up timer (IRQ0) through the 8259A ... <3> [ 0.108006] ..... (found apic 0 pin 2) ...<3> works. The full dmesg is at: http://www.sisk.pl/kernel/debug/20080618/dmesg-1.log Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
