From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: Any side effect if turn off amd_iommu Date: Mon, 4 May 2015 13:08:02 +0200 Message-ID: <20150504110802.GE15736@8bytes.org> References: <20150325140410.GS4441@8bytes.org> <20150326120547.GU4441@8bytes.org> <20150330160910.GZ4441@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: 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: AceLan Kao Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: iommu@lists.linux-foundation.org Hi Acelan, On Thu, Apr 23, 2015 at 10:15:33AM +0800, AceLan Kao wrote: > We can confirm that the issue comes from the resources conflict, > adding this boot option can solve the issue. > ivrs_ioapic[5]=00:00.1 > We've tried to negotiate with the OEM BIOS team, but they refused to > modify the BIOS code, since there is no issue on MS Windows and it'll > require to re-start a full test if the BIOS code is changed, so they > don't want to do that. > > I'm wondering if we can add a quirk to list those machine and assign > them the correct ivrs_ioapic value in amd_iommu driver? It is probably hard to match a specific machine which has the bug. What do you think would be a good indicator to check whether this BIOS bug is present? Joerg