From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCH] get rid of mmu_only parameter in emulator_write_emulated() Date: Tue, 13 Apr 2010 10:26:43 +0300 Message-ID: <20100413072643.GG23554@redhat.com> References: <20100413072156.GF23554@redhat.com> <4BC41C38.5080403@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org, mtosatti@redhat.com To: Avi Kivity Return-path: Received: from mx1.redhat.com ([209.132.183.28]:2684 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751260Ab0DMH0p (ORCPT ); Tue, 13 Apr 2010 03:26:45 -0400 Received: from int-mx04.intmail.prod.int.phx2.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.17]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o3D7Qj1c012109 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 13 Apr 2010 03:26:45 -0400 Content-Disposition: inline In-Reply-To: <4BC41C38.5080403@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Tue, Apr 13, 2010 at 10:24:40AM +0300, Avi Kivity wrote: > On 04/13/2010 10:21 AM, Gleb Natapov wrote: > >May be I am missing something here, but it seams we can call > >kvm_mmu_pte_write() directly from emulator_cmpxchg_emulated() > >instead of passing mmu_only down to emulator_write_emulated_onepage() > >and call it there. > > > > > >@@ -3460,7 +3444,9 @@ static int emulator_cmpxchg_emulated(unsigned long addr, > > if (!exchanged) > > return X86EMUL_CMPXCHG_FAILED; > > > >- return __emulator_write_emulated(addr, new, bytes, vcpu, true); > >+ kvm_mmu_pte_write(vcpu, gpa, new, bytes, 1); > >+ > >+ return X86EMUL_CONTINUE; > > > > The written range might cross a page boundary, which > kvm_mmu_pte_write() is not prepared to handle. > Don't we emulate exchange as write in this case? if (((gpa + bytes - 1) & PAGE_MASK) != (gpa & PAGE_MASK)) goto emul_write; -- Gleb.