Avi Kivity <avi@xxxxxxxxxx> writes: > On 05/03/2011 08:45 PM, OGAWA Hirofumi wrote: >> Avi Kivity<avi@xxxxxxxxxx> writes: >> >> > On 05/03/2011 07:57 PM, OGAWA Hirofumi wrote: >> >> > >> >> > Usually yes, but we already have the PIT wired to INTIN0. I saw that >> >> > the kernel consults the mptable to see which pin to use, so with the >> >> > right BIOS magic we can get things to work. >> >> >> >> Um..., I'm confused more. If so, MADT doesn't say it. MADT says irq == 0 >> >> is pin == 2, this is one of reasons why linux is quite silent in >> >> check_timer(). And I can't see why it is working by pin == 2 for IOAPIC. >> >> >> >> If I can make time, I'll see what happens by pin == 2 and pin == 0 of >> >> IOAPIC in kvm. >> > >> > You're right. The default routing is INTIN0, but qemu changes it to >> > INTIN2 and tells kvm. >> > >> > So INTIN0 is free for the 8259A output. >> >> I see. Did it mean qemu changes the wiring, so kvm can't work for live >> migration with it? > > qemu changes the wiring, but it does so on both the migration source and > the migration target (before either is launched), so they are migration > compatible. OK. So, kvm have to detect current wiring to change behavior. (E.g. nmi watchdog of IOAPIC mode without irq_ack.) IOW, if kvm can detect it, we would be able to solve issues. Would my thought be true? Thanks. -- OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
