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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 ED4BBC433E1 for ; Tue, 9 Jun 2020 09:18:32 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6B228207ED for ; Tue, 9 Jun 2020 09:18:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="ZUJJa3ce" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6B228207ED Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id EE3F5168C; Tue, 9 Jun 2020 11:17:40 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz EE3F5168C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1591694311; bh=gsgcXp42n+iMCEfph/R7BKhfW7QSbg0dXyJPXbelhIo=; h=Date:From:To:Subject:References:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=ZUJJa3ceq7ET360gkoAT9cTfmuzuL0ImDflPY09My7kUIkefOURau+Z+O4oDcQxN5 pK+wnn0y7FT9djAKmg0JUpf6SFKWeerU6KilgpeNYBeB9lWanwLrOwkZ37jlQJtByF ibH7wVEZpF/Fis36dIMnr66lI2XZ9QmirgZFl9aM= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 6F16CF80124; Tue, 9 Jun 2020 11:17:40 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 30A45F8028C; Tue, 9 Jun 2020 11:17:34 +0200 (CEST) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id DA342F80124 for ; Tue, 9 Jun 2020 11:17:29 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz DA342F80124 Received: by verein.lst.de (Postfix, from userid 2407) id 09DBF68AFE; Tue, 9 Jun 2020 11:17:28 +0200 (CEST) Date: Tue, 9 Jun 2020 11:17:27 +0200 From: Christoph Hellwig To: Takashi Iwai Subject: Re: next-0519 on thinkpad x60: sound related? window manager crash Message-ID: <20200609091727.GA23814@lst.de> References: <20200520111136.GA3802@amd> <1591545088.74ii116nf2.none@localhost> <20200608061950.GA17476@lst.de> <1591624340.z01ejtod28.none@localhost> <20200609054306.GA9606@lst.de> <20200609084305.GA21671@lst.de> 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) Cc: alsa-devel@alsa-project.org, x86@kernel.org, hpa@zytor.com, tiwai@suse.com, linux-kernel@vger.kernel.org, "Alex Xu \(Hello71\)" , hch@infradead.org, mingo@redhat.com, bp@alien8.de, Pavel Machek , David Rientjes , tglx@linutronix.de, Christoph Hellwig X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On Tue, Jun 09, 2020 at 11:09:14AM +0200, Takashi Iwai wrote: > On Tue, 09 Jun 2020 10:43:05 +0200, > Christoph Hellwig wrote: > > > > On Tue, Jun 09, 2020 at 10:05:26AM +0200, Takashi Iwai wrote: > > > > >From the disassembly it seems like a vmalloc allocation is NULL, which > > > > seems really weird as this patch shouldn't make a difference for them, > > > > and I also only see a single places that allocates the field, and that > > > > checks for an allocation failure. But the sound code is a little > > > > hard to unwind sometimes. > > > > > > It's not clear which sound device being affected, but if it's > > > HD-audio on x86, runtime->dma_area points to a vmapped buffer from > > > SG-pages allocated by dma_alloc_coherent(). > > > > > > OTOH, if it's a USB-audio, runtime->dma_area is a buffer by > > > vmalloc(). > > > > Err, you can't just vmap a buffer returned from dma_alloc_coherent, > > dma_alloc_coherent returns values are opaque and can't be used > > for virt_to_page. Whatever that code did has already been broken > > per the DMA API contract and on many architectures and just happend > > to work on x86 by accident. > > Hmm, that's bad. > > How would be a proper way to get the virtually mapped SG-buffer pages > with coherent memory? (Also allowing user-space mmap, too) dma_mmap_coherent / dma_mmap_attrs for userspace. We don't really have a good way for kernel space mappings.