From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bandan Das Subject: Re: [Qemu-devel] E5-2620v2 - emulation stop error Date: Wed, 11 Mar 2015 15:47:25 -0400 Message-ID: References: <20150311134556.GH2334@work-vm> <20150311154220.GA26463@morn.localdomain> <20150311155306.GK2334@work-vm> <20150311163739.GA29522@morn.localdomain> <20150311165203.GL2334@work-vm> <20150311173738.GD29522@morn.localdomain> <20150311175904.GN2334@work-vm> <20150311184039.GA7341@morn.localdomain> <20150311184531.GA11423@morn.localdomain> <20150311191928.GA14695@morn.localdomain> <20150311193337.GA13162@work-vm> Mime-Version: 1.0 Content-Type: text/plain Cc: "Kevin O'Connor" , Paolo Bonzini , kraxel@redhat.com, Andrey Korolyov , "qemu-devel\@nongnu.org" , "kvm\@vger.kernel.org" To: "Dr. David Alan Gilbert" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:34452 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750775AbbCKTra (ORCPT ); Wed, 11 Mar 2015 15:47:30 -0400 In-Reply-To: <20150311193337.GA13162@work-vm> (David Alan Gilbert's message of "Wed, 11 Mar 2015 19:33:37 +0000") Sender: kvm-owner@vger.kernel.org List-ID: "Dr. David Alan Gilbert" writes: > * Kevin O'Connor (kevin@koconnor.net) wrote: >> 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. > > Thanks! Looks good here. > > Andrey, Paolo, Bandan: Does it fix it for you as well? Works for me too, thanks Kevin! Bandan > Dave > >> -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 > -- > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK