From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932565AbcKPHFC (ORCPT ); Wed, 16 Nov 2016 02:05:02 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:34244 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751028AbcKPHE7 (ORCPT ); Wed, 16 Nov 2016 02:04:59 -0500 MIME-Version: 1.0 In-Reply-To: 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> From: Namhyung Kim Date: Wed, 16 Nov 2016 16:04:36 +0900 X-Google-Sender-Auth: 0M31-PvBIeYSm-KtIz8LCarky7o Message-ID: Subject: Re: [PATCH 1/3] virtio: Basic implementation of virtio pstore driver To: Paolo Bonzini Cc: "Michael S. Tsirkin" , virtio-dev@lists.oasis-open.org, Tony Luck , Kees Cook , KVM , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Anton Vorontsov , LKML , Steven Rostedt , qemu-devel , Minchan Kim , Anthony Liguori , Colin Cross , virtualization@lists.linux-foundation.org, Ingo Molnar Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Tue, Nov 15, 2016 at 11:38 PM, Paolo Bonzini wrote: > > > 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. Not sure how independent ERST is from ACPI and other specs. It looks like referencing UEFI spec at least. Btw, is the ERST used for pstore only (in Linux)? Also I need to control pstore driver like using bigger buffer, enabling specific message types and so on if ERST supports. Is it possible for ERST to provide such information? Thanks, Namhyung From mboxrd@z Thu Jan 1 00:00:00 1970 From: Namhyung Kim Subject: Re: [PATCH 1/3] virtio: Basic implementation of virtio pstore driver Date: Wed, 16 Nov 2016 16:04:36 +0900 Message-ID: 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> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: virtio-dev@lists.oasis-open.org, Tony Luck , Kees Cook , KVM , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , "Michael S. Tsirkin" , LKML , Steven Rostedt , qemu-devel , Minchan Kim , Anton Vorontsov , Anthony Liguori , Colin Cross , virtualization@lists.linux-foundation.org, Ingo Molnar To: Paolo Bonzini Return-path: In-Reply-To: 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 List-Id: kvm.vger.kernel.org Hi, On Tue, Nov 15, 2016 at 11:38 PM, Paolo Bonzini wrote: > > > 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. Not sure how independent ERST is from ACPI and other specs. It looks like referencing UEFI spec at least. Btw, is the ERST used for pstore only (in Linux)? Also I need to control pstore driver like using bigger buffer, enabling specific message types and so on if ERST supports. Is it possible for ERST to provide such information? Thanks, Namhyung From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44350) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c6uHD-0001Dm-KE for qemu-devel@nongnu.org; Wed, 16 Nov 2016 02:05:00 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c6uHC-00035z-Ru for qemu-devel@nongnu.org; Wed, 16 Nov 2016 02:04:59 -0500 Received: from mail-wm0-x243.google.com ([2a00:1450:400c:c09::243]:32845) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1c6uHC-00035n-Ku for qemu-devel@nongnu.org; Wed, 16 Nov 2016 02:04:58 -0500 Received: by mail-wm0-x243.google.com with SMTP id u144so7864211wmu.0 for ; Tue, 15 Nov 2016 23:04:58 -0800 (PST) MIME-Version: 1.0 Sender: namhyung@gmail.com In-Reply-To: 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> From: Namhyung Kim Date: Wed, 16 Nov 2016 16:04:36 +0900 Message-ID: Content-Type: text/plain; charset=UTF-8 Subject: Re: [Qemu-devel] [PATCH 1/3] virtio: Basic implementation of virtio pstore driver List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: "Michael S. Tsirkin" , virtio-dev@lists.oasis-open.org, Tony Luck , Kees Cook , KVM , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Anton Vorontsov , LKML , Steven Rostedt , qemu-devel , Minchan Kim , Anthony Liguori , Colin Cross , virtualization@lists.linux-foundation.org, Ingo Molnar Hi, On Tue, Nov 15, 2016 at 11:38 PM, Paolo Bonzini wrote: > > > 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. Not sure how independent ERST is from ACPI and other specs. It looks like referencing UEFI spec at least. Btw, is the ERST used for pstore only (in Linux)? Also I need to control pstore driver like using bigger buffer, enabling specific message types and so on if ERST supports. Is it possible for ERST to provide such information? Thanks, Namhyung