On Sun, May 30, 2010 at 8:07 PM, Gleb Natapov <g...@redhat.com> wrote: > On Sun, May 30, 2010 at 07:37:59PM +0000, Blue Swirl wrote: >> On Sun, May 30, 2010 at 1:49 PM, Gleb Natapov <g...@redhat.com> wrote: >> > On Sun, May 30, 2010 at 12:56:26PM +0000, Blue Swirl wrote: >> >> >> Well, I'd like to get the test program also trigger it. Now I'm >> >> >> getting: >> >> >> apic: write: 00000350 = 00000000 >> >> >> apic: apic_reset_irq_delivered: old coalescing 0 >> >> >> apic: apic_local_deliver: vector 3 delivery mode 0 >> >> >> apic: apic_set_irq: coalescing 1 >> >> >> apic: apic_get_irq_delivered: returning coalescing 1 >> >> >> apic: apic_reset_irq_delivered: old coalescing 1 >> >> >> apic: apic_local_deliver: vector 3 delivery mode 0 >> >> >> apic: apic_set_irq: coalescing 0 >> >> >> apic: apic_get_irq_delivered: returning coalescing 0 >> >> >> apic: apic_reset_irq_delivered: old coalescing 0 >> >> >> apic: apic_local_deliver: vector 3 delivery mode 0 >> >> >> apic: apic_set_irq: coalescing 0 >> >> >> >> > So interrupt is _alway_ coalesced. If apic_get_irq_delivered() returns >> > 0 it means the interrupt was not delivered. >> >> That seems strange. I changed the program so that the handler gets >> executed, also output a dot to serial from the handler. I changed the >> frequency to 2Hz. >> >> Now, if I leave out -rtc-td-hack, I get the dots at 2Hz as expected. >> With -rtc-td-hack, the dots come out much faster. I added >> DEBUG_COALESCING also to RTC, with that enabled I get: >> qemu -L . -bios coalescing.bin -d in_asm,int -no-hpet -rtc-td-hack -serial >> stdio >> cmos: coalesced irqs scaled to 0 >> cmos: coalesced irqs increased to 1 >> cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> .cmos: injecting on ack >> ..cmos: injecting from timer >> .cmos: coalesced irqs increased to 2 >> cmos: injecting on ack >> >> So, there are bogus injections. > > Looks like irr in apic is never cleared. Probably bug in userspace apic > emulation. I'll look into it. Try to route interrupt via APIC (not ExtInt), > or use qemu-kvm with in kernel irq chip.
With APIC you mean Fixed? Then the IRQ is not delivered at all.