From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:45265) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SorPf-0001TJ-VF for qemu-devel@nongnu.org; Wed, 11 Jul 2012 03:32:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SorPZ-0005sd-NT for qemu-devel@nongnu.org; Wed, 11 Jul 2012 03:32:43 -0400 Received: from mail-we0-f173.google.com ([74.125.82.173]:62454) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SorPZ-0005sF-ES for qemu-devel@nongnu.org; Wed, 11 Jul 2012 03:32:37 -0400 Received: by weyz53 with SMTP id z53so580356wey.4 for ; Wed, 11 Jul 2012 00:32:35 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <4FFAD54D.2050909@suse.de> References: <1340197164-9574-1-git-send-email-imammedo@redhat.com> <1340197164-9574-4-git-send-email-imammedo@redhat.com> <4FE1D1BB.6030709@suse.de> <4FFAB99E.1030203@redhat.com> <4FFAD54D.2050909@suse.de> From: liu ping fan Date: Wed, 11 Jul 2012 15:32:14 +0800 Message-ID: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 3/5] target-i386: call x86_cpu_realize() after APIC is initialized. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?ISO-8859-1?Q?Andreas_F=E4rber?= Cc: peter.maydell@linaro.org, aliguori@us.ibm.com, ehabkost@redhat.com, Jan Kiszka , mtosatti@redhat.com, qemu-devel@nongnu.org, mdroth@linux.vnet.ibm.com, blauwirbel@gmail.com, avi@redhat.com, pbonzini@redhat.com, igor On Mon, Jul 9, 2012 at 8:57 PM, Andreas F=E4rber wrote: > Am 09.07.2012 12:59, schrieb igor: >> On 06/20/2012 03:35 PM, Andreas F=E4rber wrote: >>> Am 20.06.2012 14:59, schrieb Igor Mammedov: >>>> It's not correct to make CPU runnable (i.e. calling x86_cpu_realize()) >>>> when not all properties are set (APIC in this case). >>>> >>>> Fix it by calling x86_cpu_realize() at board level after APIC is >>>> initialized, right before cpu_reset(). >>>> >>>> Signed-off-by: Igor Mammedov >>>> --- >>>> hw/pc.c | 1 + >>>> target-i386/helper.c | 2 -- >>>> 2 files changed, 1 insertion(+), 2 deletions(-) >>>> >>>> diff --git a/hw/pc.c b/hw/pc.c >>>> index 8368701..8a662cf 100644 >>>> --- a/hw/pc.c >>>> +++ b/hw/pc.c >>>> @@ -948,6 +948,7 @@ static X86CPU *pc_new_cpu(const char *cpu_model) >>>> env->apic_state =3D apic_init(env, env->cpuid_apic_id); >>>> } >>>> qemu_register_reset(pc_cpu_reset, cpu); >>>> + x86_cpu_realize(OBJECT(cpu), NULL); >>>> pc_cpu_reset(cpu); >>>> return cpu; >>>> } >>>> diff --git a/target-i386/helper.c b/target-i386/helper.c >>>> index c52ec13..b38ea7f 100644 >>>> --- a/target-i386/helper.c >>>> +++ b/target-i386/helper.c >>>> @@ -1161,8 +1161,6 @@ X86CPU *cpu_x86_init(const char *cpu_model) >>>> return NULL; >>>> } >>>> >>>> - x86_cpu_realize(OBJECT(cpu), NULL); >>>> - >>>> return cpu; >>>> } >>>> >>> >>> This will require changes in linux-user and possibly bsd-user. Having a >>> cpu_realize() would probably help with avoiding #ifdef'ery. >>> Unfortunately deriving CPUState from DeviceState proves a bit difficult >>> in the meantime (it worked at one point, now there's lots of circular >>> header dependencies), and realize support for Object got stopped. >>> >> As alternative to keep, I could leave x86_cpu_realize() in >> cpu_x86_init() and keep pc_cpu_reset() in pc_new_cpu(). That will result >> in calling cpu_reset() 3 instead of 2 times. >> Later when apic_init is moved inside cpu.c, a pc_cpu_reset() in >> pc_new_cpu() would be unnecessary and could be cleaned up then. > > Let me explain in more detail what I was thinking about: cpu_init() and > cpu_x86_init() today return an initialized/realized object. I don't want > bugs to creep into the user emulators because someone is not aware that > x86 is semantically differing from all other targets. > > What I did for a qemu-rl78 machine is to inline cpu_rl78_init() so that > I could put code in between, i.e., for x86: object_new(), APIC/BSP > stuff, x86_cpu_realize(). That way any addition to the realize function > will still affect the user emulators. > The downside is that when we add x86 CPU subclasses we'd have to What do you mean " add x86 CPU subclasses" ? Derive from class X86CPU ? And any scene for that? Thanks, pingfan > remember to update two places. The solution to that would be to split > out a x86_cpu_new() function used from cpu_x86_init() and wherever you > need it for the PC machine. Then the code is still maintainable in one > central place and you get to do your APIC cleanups, and we don't depend > on a central realize implementation or device parent, what do you think? > > Regards, > Andreas > > -- > SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg, Germany > GF: Jeff Hawn, Jennifer Guild, Felix Imend=F6rffer; HRB 16746 AG N=FCrnbe= rg > > >