From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: amdgpu/TTM oopses since merging swiotlb_dma_ops into the dma_direct code Date: Thu, 10 Jan 2019 12:05:58 -0500 Message-ID: <20190110170557.GD27546@char.us.oracle.com> References: <61f8f660-005c-190c-c08f-b563de2eae18@daenzer.net> <20190110135741.GA9255@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable 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: Sibren Vasse Cc: Sibren Vasse , Michel =?iso-8859-1?Q?D=E4nzer?= , x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, Robin Murphy , Christoph Hellwig List-Id: amd-gfx.lists.freedesktop.org On Thu, Jan 10, 2019 at 04:26:43PM +0100, Sibren Vasse wrote: > On Thu, 10 Jan 2019 at 14:57, Christoph Hellwig wrote: > > > > On Thu, Jan 10, 2019 at 10:59:02AM +0100, Michel D=E4nzer wrote: > > > > > > Hi Christoph, > > > > > > > > > https://bugs.freedesktop.org/109234 (please ignore comments #6-#9) was > > > bisected to your commit 55897af63091 "dma-direct: merge swiotlb_dma_o= ps > > > into the dma_direct code". Any ideas? > > > > From the trace it looks like we git the case where swiotlb tries > > to copy back data from a bounce buffer, but hits a dangling or NULL > > pointer. So a couple questions for the submitter: > My apologies if I misunderstand something, this subject matter is new to = me. > = > > > > - does the system have more than 4GB memory and thus use swiotlb? > My system has 8GB memory. The other report on the bug tracker had 16GB. > = > > (check /proc/meminfo, and if something SWIOTLB appears in dmesg) > /proc/meminfo: https://ptpb.pw/4rxI > Can I grep dmesg for a string? Can you attach the 'dmesg'? = > = > > - does the device this happens on have a DMA mask smaller than > > the available memory, that is should swiotlb be used here to start > > with? > It's a MSI Radeon RX 570 Gaming X 4GB. The other report was a RX 580. > lshw output: https://ptpb.pw/6s0H > = > = > Regards, > = > Sibren