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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 54267C4321A for ; Tue, 11 Jun 2019 06:08:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3580F20820 for ; Tue, 11 Jun 2019 06:08:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391144AbfFKGIq (ORCPT ); Tue, 11 Jun 2019 02:08:46 -0400 Received: from verein.lst.de ([213.95.11.211]:48379 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391044AbfFKGIq (ORCPT ); Tue, 11 Jun 2019 02:08:46 -0400 Received: by newverein.lst.de (Postfix, from userid 2407) id 29D2768B02; Tue, 11 Jun 2019 08:08:17 +0200 (CEST) Date: Tue, 11 Jun 2019 08:08:16 +0200 From: Christoph Hellwig To: Benjamin Herrenschmidt Cc: Larry Finger , Aaro Koskinen , Christoph Hellwig , Christian Zigotzky , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [BISECTED REGRESSION] b43legacy broken on G4 PowerBook Message-ID: <20190611060816.GA20158@lst.de> References: <20190605225059.GA9953@darkstar.musicnaut.iki.fi> <73da300c-871c-77ac-8a3a-deac226743ef@lwfinger.net> <7697a9d10777b28ae79fdffdde6d0985555f6310.camel@kernel.crashing.org> <3ed1ccfe-d7ca-11b9-17b3-303d1ae1bb0f@lwfinger.net> 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-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Tue, Jun 11, 2019 at 03:56:33PM +1000, Benjamin Herrenschmidt wrote: > The reason I think it sort-of-mostly-worked is that to get more than > 1GB of RAM, those machines use CONFIG_HIGHMEM. And *most* network > buffers aren't allocated in Highmem.... so you got lucky. > > That said, there is such as thing as no-copy send on network, so I > wouldn't be surprised if some things would still have failed, just not > frequent enough for you to notice. Unless NETIF_F_HIGHDMA is set on a netdev, the core networkign code will bounce buffer highmem pages for the driver under all circumstances. 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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 63657C4321A for ; Tue, 11 Jun 2019 06:10:39 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 16BC920820 for ; Tue, 11 Jun 2019 06:10:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 16BC920820 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45NKP91WBtzDqVP for ; Tue, 11 Jun 2019 16:10:37 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=newverein.lst.de; envelope-from=hch@lst.de; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Received: from newverein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45NKM26stBzDqS9 for ; Tue, 11 Jun 2019 16:08:46 +1000 (AEST) Received: by newverein.lst.de (Postfix, from userid 2407) id 29D2768B02; Tue, 11 Jun 2019 08:08:17 +0200 (CEST) Date: Tue, 11 Jun 2019 08:08:16 +0200 From: Christoph Hellwig To: Benjamin Herrenschmidt Subject: Re: [BISECTED REGRESSION] b43legacy broken on G4 PowerBook Message-ID: <20190611060816.GA20158@lst.de> References: <20190605225059.GA9953@darkstar.musicnaut.iki.fi> <73da300c-871c-77ac-8a3a-deac226743ef@lwfinger.net> <7697a9d10777b28ae79fdffdde6d0985555f6310.camel@kernel.crashing.org> <3ed1ccfe-d7ca-11b9-17b3-303d1ae1bb0f@lwfinger.net> 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) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Aaro Koskinen , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, Christian Zigotzky , linuxppc-dev@lists.ozlabs.org, Christoph Hellwig , Larry Finger Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Tue, Jun 11, 2019 at 03:56:33PM +1000, Benjamin Herrenschmidt wrote: > The reason I think it sort-of-mostly-worked is that to get more than > 1GB of RAM, those machines use CONFIG_HIGHMEM. And *most* network > buffers aren't allocated in Highmem.... so you got lucky. > > That said, there is such as thing as no-copy send on network, so I > wouldn't be surprised if some things would still have failed, just not > frequent enough for you to notice. Unless NETIF_F_HIGHDMA is set on a netdev, the core networkign code will bounce buffer highmem pages for the driver under all circumstances.