From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938571AbcKOOi5 (ORCPT ); Tue, 15 Nov 2016 09:38:57 -0500 Received: from mx1.redhat.com ([209.132.183.28]:41242 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755419AbcKOOit (ORCPT ); Tue, 15 Nov 2016 09:38:49 -0500 Subject: Re: [PATCH 1/3] virtio: Basic implementation of virtio pstore driver To: Namhyung Kim References: <20160820080744.10344-1-namhyung@kernel.org> <20160820080744.10344-2-namhyung@kernel.org> <20161110182611-mutt-send-email-mst@kernel.org> <20161115045021.GA15992@danjae.aot.lge.com> <20161115065658-mutt-send-email-mst@kernel.org> <20161115143629.GA29740@danjae.aot.lge.com> Cc: "Michael S. Tsirkin" , virtio-dev@lists.oasis-open.org, Tony Luck , Kees Cook , kvm@vger.kernel.org, =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Anton Vorontsov , LKML , Steven Rostedt , qemu-devel@nongnu.org, Minchan Kim , Anthony Liguori , Colin Cross , virtualization@lists.linux-foundation.org, Ingo Molnar From: Paolo Bonzini Message-ID: Date: Tue, 15 Nov 2016 15:38:42 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161115143629.GA29740@danjae.aot.lge.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Tue, 15 Nov 2016 14:38:49 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 15/11/2016 15:36, Namhyung Kim wrote: > Hi, > > On Tue, Nov 15, 2016 at 10:57:29AM +0100, Paolo Bonzini wrote: >> >> >> On 15/11/2016 06:06, Michael S. Tsirkin wrote: >>> On Tue, Nov 15, 2016 at 01:50:21PM +0900, Namhyung Kim wrote: >>>> Hi Michael, >>>> >>>> On Thu, Nov 10, 2016 at 06:39:55PM +0200, Michael S. Tsirkin wrote: >>>>> On Sat, Aug 20, 2016 at 05:07:42PM +0900, Namhyung Kim wrote: >>>>>> The virtio pstore driver provides interface to the pstore subsystem so >>>>>> that the guest kernel's log/dump message can be saved on the host >>>>>> machine. Users can access the log file directly on the host, or on the >>>>>> guest at the next boot using pstore filesystem. It currently deals with >>>>>> kernel log (printk) buffer only, but we can extend it to have other >>>>>> information (like ftrace dump) later. >>>>>> >>>>>> It supports legacy PCI device using single order-2 page buffer. >>>>> >>>>> Do you mean a legacy virtio device? I don't see why >>>>> you would want to support pre-1.0 mode. >>>>> If you drop that, you can drop all cpu_to_virtio things >>>>> and just use __le accessors. >>>> >>>> I was thinking about the kvmtools which lacks 1.0 support AFAIK. >>> >>> Unless kvmtools wants to be left behind it has to go 1.0. >> >> And it also has to go ACPI. Is there any reason, apart from kvmtool, to >> make a completely new virtio device, with no support in existing guests, >> rather than implement ACPI ERST? > > Well, I know nothing about ACPI. It looks like a huge spec and I > don't want to dig into it just for this. ERST (error record serialization table) is a small subset of the ACPI spec. Paolo