From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: BUG at drivers/iommu/amd_iommu.c:1436! Date: Mon, 21 Nov 2016 16:32:50 +0100 Message-ID: <20161121153250.GE2078@8bytes.org> References: <838275de-6cac-93d8-ca04-54b06a24b3d4@compro.net> <20161117214141.GC2078@8bytes.org> <20161117220045.GD2078@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: Mark Hounschell Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Linux-kernel List-Id: iommu@lists.linux-foundation.org On Fri, Nov 18, 2016 at 09:04:05AM -0500, Mark Hounschell wrote: > OK. It's attached. > [ 45.033715] WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:1158 check_unmap+0x4ef/0x990 > [ 45.037651] 3c59x 0000:04:04.0: DMA-API: device driver failed to check map error[device address=0x00000000ffedf840] [size=1536 bytes] [mapped as single] Okay, there is a dma-debug warning from the 3c59x driver. Can you please blacklist this driver (or compile it out) and re-try? The dma-debug code will only show the first warning and stop then. So any possible warnings from your out-of-tree driver will not be shown as long as the 3c59x driver is loaded. Alternativly you can write 1 to dma-api/all_errors in debug-fs so that it will show all errors. But I suggest to unload the 3com driver first and then load your driver. Joerg