From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH 06/10] iommu/amd: Add functions copy_command_buffer/copy_event_buffer Date: Tue, 29 Sep 2015 18:04:39 +0200 Message-ID: <20150929160439.GN3036@8bytes.org> References: <1443076656-31776-1-git-send-email-bhe@redhat.com> <1443076656-31776-7-git-send-email-bhe@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1443076656-31776-7-git-send-email-bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Baoquan He Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Thu, Sep 24, 2015 at 02:37:32PM +0800, Baoquan He wrote: > Copy command buffer and event buffer from the old to kdump kernel. > > Still there are 2 problems: > 1) Not very sure if this is necessary. If do not copy the old command buffer, and > only set the newly allocated command buffer, is there anything wrong? No, there is no need to copy command and event buffers. Just make sure they get re-initialized and flush all iommu caches after setting the new device table. Joerg From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934899AbbI2QEu (ORCPT ); Tue, 29 Sep 2015 12:04:50 -0400 Received: from 8bytes.org ([81.169.241.247]:56645 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932168AbbI2QEl (ORCPT ); Tue, 29 Sep 2015 12:04:41 -0400 Date: Tue, 29 Sep 2015 18:04:39 +0200 From: Joerg Roedel To: Baoquan He Cc: iommu@lists.linux-foundation.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 06/10] iommu/amd: Add functions copy_command_buffer/copy_event_buffer Message-ID: <20150929160439.GN3036@8bytes.org> References: <1443076656-31776-1-git-send-email-bhe@redhat.com> <1443076656-31776-7-git-send-email-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1443076656-31776-7-git-send-email-bhe@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 24, 2015 at 02:37:32PM +0800, Baoquan He wrote: > Copy command buffer and event buffer from the old to kdump kernel. > > Still there are 2 problems: > 1) Not very sure if this is necessary. If do not copy the old command buffer, and > only set the newly allocated command buffer, is there anything wrong? No, there is no need to copy command and event buffers. Just make sure they get re-initialized and flush all iommu caches after setting the new device table. Joerg