From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH] iommu/vt-d: Flush old iotlb for kdump when the device gets context mapped Date: Tue, 29 Nov 2016 15:35:47 +0100 Message-ID: <20161129143547.GG2078@8bytes.org> References: <1479286950-21885-1-git-send-email-xlpang@redhat.com> <582C232F.6080205@redhat.com> <582D1A40.409@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: <582D1A40.409-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: xlpang-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Cc: Don Brace , Myron Stowe , kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, LKML , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Dave Young , David Woodhouse List-Id: iommu@lists.linux-foundation.org On Thu, Nov 17, 2016 at 10:47:28AM +0800, Xunlei Pang wrote: > As per the comment, the code here only needs to flush context caches > for the special domain 0 which is used to tag the > non-present/erroneous caches, seems we should flush the old domain id > of present entries for kdump according to the analysis, other than the > new-allocated domain id. Let me ponder more on this. Flushing the context entry only is fine. The old domain-id will not be re-used anyway, so there is no point in reading it out of the context table and flush it. Also, please add a Fixes-tag when you re-post this patch. Joerg