[Qemu-devel] Win2k broken by kvmvapic

[Blue Swirl]

Hi,

Win2k does not work in HEAD, it resets the machine. I bisected this to
0b57e287138728f72d88b06e69b970c5d745c44a, but that does not look so
buggy.

Digging deeper, the problem is introduced by kvmvapic:
Breakpoint 1, cpu_physical_memory_write_rom (addr=0xca300,
    buf=0x7fffec66b500 "", len=0x5) at /src/qemu/exec.c:3536
3536                invalidate_and_set_dirty(addr1, l);
(gdb) bt
#0  cpu_physical_memory_write_rom (addr=0xca300, buf=0x7fffec66b500 "",
    len=0x5) at /src/qemu/exec.c:3536
#1  0x0000000000644089 in apic_sync_vapic (s=0x1a6ba60, sync_type=0x2)
    at /src/qemu/hw/i386/../apic.c:132

It looks like vapic is enabled even with KVM disabled and this causes
chaos. With -global apic.vapic=false Win2k works.

Maybe vapic shouldn't be enabled at all if KVM is not available and
apic_common.c needs kvm_enabled() checks before using vapic?