From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e39.co.us.ibm.com (e39.co.us.ibm.com [32.97.110.160]) (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id EB7D41A0007 for ; Wed, 13 May 2015 08:07:42 +1000 (AEST) Received: from /spool/local by e39.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 12 May 2015 16:07:40 -0600 Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 0A9B81FF001E for ; Tue, 12 May 2015 15:58:49 -0600 (MDT) Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t4CM5Xuo23855292 for ; Tue, 12 May 2015 15:05:33 -0700 Received: from d03av03.boulder.ibm.com (localhost [127.0.0.1]) by d03av03.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t4CM7cqm001526 for ; Tue, 12 May 2015 16:07:38 -0600 Message-ID: <555279A8.6060906@linux.vnet.ibm.com> Date: Tue, 12 May 2015 17:07:36 -0500 From: Brian King MIME-Version: 1.0 To: Sreekanth Reddy , Benjamin Herrenschmidt Subject: mpt2sas DMA mask Content-Type: text/plain; charset=utf-8 Cc: linuxppc-dev , linux-scsi List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The mpt2sas driver was changed late last year in that it now requests a 64 bit DMA mask, then requests a 32 bit coherent DMA mask, then later requests a 64 bit coherent DMA mask. This was 5fb1bf8aaa832e1e9ca3198de7bbecb8eff7db9c. This breaks 64 bit DMA support for mpt2sas on Power and we always fall back to using 32 bit DMA. Looking at the commit log, it looks like this was an intentional change. Ben - you had a patch set you had posted to the list back in Feb of this year, but it doesn't look like it got merged. https://lists.ozlabs.org/pipermail/linuxppc-dev/2015-February/125087.html This would fix the issue I'm seeing on mpt2sas. Do you plan to dust that patch set off and upstream it? Were there issues with it that still need to be resolved? Thanks, Brian -- Brian King Power Linux I/O IBM Linux Technology Center