On 08/14/2012 01:44 PM, Jan Kiszka wrote: > On 2012-08-14 12:20, Avi Kivity wrote: >> On 08/14/2012 11:44 AM, Markus Armbruster wrote: >>> >>> Next error: >>> >>> $ gdb --args qemu-system-x86_64 -nodefaults --enable-kvm -vnc :0 >>> -monitor stdio -m 640k >>> [...] >>> Program received signal SIGSEGV, Segmentation fault. >>> [...] >>> (gdb) bt >>> #0 0x0000003b0de884ac in __memcmp_sse2 () from /lib64/libc.so.6 >>> #1 0x000000000063f1ad in patch_hypercalls (s=0x139b350) >>> at /work/armbru/qemu/hw/i386/../kvmvapic.c:532 >>> #2 0x000000000063f3fe in vapic_prepare (s=0x139b350) >>> at /work/armbru/qemu/hw/i386/../kvmvapic.c:597 >>> #3 0x000000000063f4ed in vapic_write (opaque=0x139b350, addr=0, >>> data=32, size= >>> 2) at /work/armbru/qemu/hw/i386/../kvmvapic.c:634 >>> #4 0x0000000000677a44 in memory_region_write_accessor >>> (opaque=0x139d670, addr= >>> >>> Happens when -m argument is a multiple of 4k in [648k..768k]. Only with >>> --enable-kvm. With and without my CMOS fix applied. >> >> kvmvapic requires RAM to be present underneath the ROM. We could fix up >> kvmvapic to allocate a 4k region and insert it as an overlay, but it's >> sufficient IMO to require sub-1M users to disable it. It won't be of >> any use to the anyway as Windows XP requires more than 1MB. > > We can also easily automatically disable it when there is insufficient > (<1MB) memory. Will post a patch.
Would be nicer if it auto-disables itself, but don't know if the option ROM has access to the memory size. -- error compiling committee.c: too many arguments to function
