kvm-unit-tests was keeping DS/ES/FS/GS loaded with the segment descriptors provided by the multiboot boot loader (which are 32-bit), and instead loading SS with 0. The vmx.flat test failed because KVM did not like doing writes into such an SS. Load again the segment registers after entering 64-bit mode, for both the BSP and the APs. Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> --- x86/cstart64.S | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/x86/cstart64.S b/x86/cstart64.S index 8d0d95d..8d5ee2d 100644 --- a/x86/cstart64.S +++ b/x86/cstart64.S @@ -213,7 +213,11 @@ idt_descr: load_tss: lidtq idt_descr - mov $0, %eax + mov $0x10, %eax + mov %ax, %ds + mov %ax, %es + mov %ax, %fs + mov %ax, %gs mov %ax, %ss mov $(APIC_DEFAULT_PHYS_BASE + APIC_ID), %eax mov (%rax), %eax -- 1.8.3.1 -- 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