On Wed, Mar 11, 2015 at 02:45:31PM -0400, Kevin O'Connor wrote: > On Wed, Mar 11, 2015 at 02:40:39PM -0400, Kevin O'Connor wrote: > > For what it's worth, I can't seem to trigger the problem if I move the > > cmos read above the SIPI/LAPIC code (see patch below). > > Ugh! > > That's a seabios bug. Main processor modifies the rtc index > (rtc_read()) while APs try to clear the NMI bit by modifying the rtc > index (romlayout.S:transition32). > > I'll put together a fix. The seabios patch below resolves the issue for me. -Kevin --- a/src/romlayout.S +++ b/src/romlayout.S @@ -22,7 +22,8 @@ // %edx = return location (in 32bit mode) // Clobbers: ecx, flags, segment registers, cr0, idt/gdt DECLFUNC transition32 -transition32_for_smi: +transition32_nmi_off: + // transition32 when NMI and A20 are already initialized movl %eax, %ecx jmp 1f transition32: @@ -205,7 +206,7 @@ __farcall16: entry_smi: // Transition to 32bit mode. movl $1f + BUILD_BIOS_ADDR, %edx - jmp transition32_for_smi + jmp transition32_nmi_off .code32 1: movl $BUILD_SMM_ADDR + 0x8000, %esp calll _cfunc32flat_handle_smi - BUILD_BIOS_ADDR @@ -216,8 +217,10 @@ entry_smi: DECLFUNC entry_smp entry_smp: // Transition to 32bit mode. + cli + cld movl $2f + BUILD_BIOS_ADDR, %edx - jmp transition32 + jmp transition32_nmi_off .code32 // Acquire lock and take ownership of shared stack 1: rep ; nop -- 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