From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: DANGER WILL ROBINSON, DANGER Date: Thu, 3 Oct 2019 17:50:49 +0200 Message-ID: References: <20190905180955.GA3251@redhat.com> <5b0966de-b690-fb7b-5a72-bc7906459168@redhat.com> <20191002192714.GA5020@redhat.com> <20191002141542.GA5669@redhat.com> <20191002170429.GA8189@redhat.com> <20191003154233.GA4421@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20191003154233.GA4421@redhat.com> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Jerome Glisse Cc: Tamas K Lengyel , Weijiang Yang , Yu C , "kvm@vger.kernel.org" , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Jan Kiszka , =?UTF-8?Q?Samuel_Laur=c3=a9n?= , Konrad Rzeszutek Wilk , Matthew Wilcox , "virtualization@lists.linux-foundation.org" , =?UTF-8?Q?Adalbert_Laz=c4=83r?= , "linux-mm@kvack.org" , Patrick Colp , Mathieu Tarral , Stefan Hajnoczi , Mircea CIRJALIU - MELIU , =?UTF-8?Q?Mihai_Don=c8=9bu?= List-Id: virtualization@lists.linuxfoundation.org On 03/10/19 17:42, Jerome Glisse wrote: > All that is needed is to make sure that vm_normal_page() will see those > pte (inside the process that is mirroring the other process) as special > which is the case either because insert_pfn() mark the pte as special or > the kvm device driver which control the vm_operation struct set a > find_special_page() callback that always return NULL, or the vma has > either VM_PFNMAP or VM_MIXEDMAP set (which is the case with insert_pfn). > > So you can keep the existing kvm code unmodified. Great, thanks. And KVM is already able to handle VM_PFNMAP/VM_MIXEDMAP, so that should work. Paolo