On (Wed) Feb 18 2009 [13:21:26], Amit Shah wrote: > On (Tue) Feb 17 2009 [12:47:10], Brian Kress wrote: > > When I try to run KVM built off the current head, it crashes with a > > Segmentation fault. KVM-84 does > > not. Seems to be dealing with the CPUID changes: > > > > > > 0x081a5c70 in host_cpuid () > > at /home/kressb/kvm/src/qemu/target-i386/helper.c:1426 > > 1426 asm volatile("pusha \n\t" > > This looks like some kind of stack corruption on 32-bit: > > 1472 if (kvm_enabled()) > (gdb) > 1473 host_cpuid(0, 0, NULL, ebx, ecx, edx); > (gdb) > > Program received signal SIGSEGV, Segmentation fault. > 0x081a2d60 in host_cpuid (function=10, count=1231384169, eax=0x0, ebx=0xadfc1914, > ecx=0xadfc1910, edx=0xadfc190c) > at /home/amit/src/kvm-userspace/qemu/target-i386/helper.c:1426 > 1426 asm volatile("pusha \n\t" > > I don't see this on 64-bit. Investigating. Avi, what's the reason for doing this in the host_cpuid code? As I see it, the first version should work for both 64-bit and 32-bit code. #ifdef __x86_64__ asm volatile("cpuid" : "=a"(vec[0]), "=b"(vec[1]), "=c"(vec[2]), "=d"(vec[3]) : "0"(function), "c"(count) : "cc"); #else asm volatile("pusha \n\t" "cpuid \n\t" "mov %%eax, 0(%1) \n\t" "mov %%ebx, 4(%1) \n\t" "mov %%ecx, 8(%1) \n\t" "mov %%edx, 12(%1) \n\t" "popa" : : "a"(function), "c"(count), "S"(vec) : "memory", "cc"); #endif Amit -- 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