From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 95650C43381 for ; Tue, 19 Feb 2019 15:16:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B3CA20700 for ; Tue, 19 Feb 2019 15:16:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726565AbfBSPQM (ORCPT ); Tue, 19 Feb 2019 10:16:12 -0500 Received: from verein.lst.de ([213.95.11.211]:52488 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727846AbfBSPQM (ORCPT ); Tue, 19 Feb 2019 10:16:12 -0500 Received: by newverein.lst.de (Postfix, from userid 2407) id DEF7668CEC; Tue, 19 Feb 2019 16:16:09 +0100 (CET) Date: Tue, 19 Feb 2019 16:16:09 +0100 From: Christoph Hellwig To: Meelis Roos Cc: linux-parisc@vger.kernel.org, Christoph Hellwig , iommu@lists.linux-foundation.org Subject: Re: zalon scsi WARNINGs at kernel/dma/mapping.c:290 dma_free_attrs+0x5c/0x84 Message-ID: <20190219151609.GA4121@lst.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org On Tue, Feb 19, 2019 at 12:57:18AM +0200, Meelis Roos wrote: > I tried latest Linux on HP A180C (32-bit pa-risc). It works but the Zalon SCSI driver barfs warnings for GSC addon differential scsi board. > > The warnings seem to be DMA API related. Packaged 4.19 and self-compiled 5.0.0-rc7 exhibit the same problem. It looks like the driver is trying to free DMA coherent memory with irqs disabled, which is a big no-go on most non-coherent architectures (which includes parisc). The DMA coherent code in this driver is pretty convoluted, but I'll see what I can do. The warning has been there for a couple kernel release, and the issue basically goes back to day 0 of support for non-coherent architectures.