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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6DD0CCA482 for ; Thu, 30 Jun 2022 19:22:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236598AbiF3TWI (ORCPT ); Thu, 30 Jun 2022 15:22:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236257AbiF3TWH (ORCPT ); Thu, 30 Jun 2022 15:22:07 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B108243390 for ; Thu, 30 Jun 2022 12:22:05 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id 145so225756pga.12 for ; Thu, 30 Jun 2022 12:22:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=l005vzshb3NCX9X2VM+PRHsKSH+cwoE8+hpxYOqA4As=; b=Ryekk371jQ1QiVX/pYGZ1Fxnqlqp0Twrw4fdw7rwXdWNZd8linJuCpYUZVY+Q0iPyf MQtHmLDECOfQliv0UkVXxBpP1oEkjtqBA+m+vXUw7eTKeZQm+pLSA86FeQvRbD+P0G11 vgeXEKD6isj/F1Ee/eKIdEVU/vkXQM/wI5kbLINfslHCrrzOI44xnSHDUGCbhqvwVddM j34tTrE1+UG2QZsXwyPCsEBPg2rxRpPI3L1pBalHzCrfK7rgExkmBMwK3cN5a26ttPxc nujxQaN3aRGOZJRNQAC0dUIV+4oE8cjHO5gI3kzVIoJ4RZMsmRwklddwhggK/OvBOGty iS1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=l005vzshb3NCX9X2VM+PRHsKSH+cwoE8+hpxYOqA4As=; b=045nPR0Wn8SPUNuL5OtFUswvzWUMnEa5kgyFIYrl9/7YPcVp+tCN89S1Bo12rcZb5A q47lVNux+V6n1m6/e8Ozirhes99Ouqw9WBHKPTzHEXcEtlh1malBKRMGdSfkro2TE20z pjQ3p3D5hjLoS+5eurZyf+zv64Ybus0VAHvT9m87CUZzb4doVp9xHyuJ1B1w1e2XxY3V oWcPSTXCDTm6NW7j04q+p+A+DqAcLAsng41bCUujKnWdCOOWpGaTdk5bBuPLNGXJi9yv Bm9NwtoNgjI6k/lHiiXdkxVGZ8cuEEbAUubP3NY4BnhJyJmQvhFBfcyz8V7jFCYnn+Y2 bIVw== X-Gm-Message-State: AJIora+nK8xBLsPAvcVt8tZKeOJQUTnury3/deI8o/TaRlTKwPHK6Lwf SPgXBohaivMcoAXpIv0/bQY= X-Google-Smtp-Source: AGRyM1slOrPQAMr1SPYrSza35gnZ53yO5OmKuyILVUgGuCU6HEAC2pr8Byjfbqxc2GodF/4gt0QEFw== X-Received: by 2002:a05:6a00:21c8:b0:4fd:f89f:ec0e with SMTP id t8-20020a056a0021c800b004fdf89fec0emr17286632pfj.83.1656616925098; Thu, 30 Jun 2022 12:22:05 -0700 (PDT) Received: from ?IPV6:2001:df0:0:200c:b411:35d2:9458:bbe5? ([2001:df0:0:200c:b411:35d2:9458:bbe5]) by smtp.gmail.com with ESMTPSA id q13-20020a170902a3cd00b0016403cae7desm13907355plb.276.2022.06.30.12.21.56 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 30 Jun 2022 12:22:03 -0700 (PDT) Message-ID: Date: Fri, 1 Jul 2022 07:21:53 +1200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH v2 3/3] arch/*/: remove CONFIG_VIRT_TO_BUS Content-Language: en-US To: Christoph Hellwig Cc: Arnd Bergmann , Geert Uytterhoeven , scsi , Linux Kernel Mailing List , Arnd Bergmann , Jakub Kicinski , Marek Szyprowski , Robin Murphy , Linux IOMMU , Khalid Aziz , "Maciej W . Rozycki" , Matt Wang , Miquel van Smoorenburg , Mark Salyzyn , linuxppc-dev , Linux-Arch , alpha , linux-m68k , Parisc List , Denis Efremov , Michael Ellerman , John Paul Adrian Glaubitz References: <20220617125750.728590-1-arnd@kernel.org> <20220617125750.728590-4-arnd@kernel.org> <6ba86afe-bf9f-1aca-7af1-d0d348d75ffc@gmail.com> <9289fd82-285c-035f-5355-4d70ce4f87b0@gmail.com> <9f812d3d-0fcd-46e6-6d7e-6d4bf66f24ab@gmail.com> From: Michael Schmitz In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-m68k@vger.kernel.org Hi Christoph, On 29/06/22 18:21, Christoph Hellwig wrote: > On Wed, Jun 29, 2022 at 11:09:00AM +1200, Michael Schmitz wrote: >> And all SCSI buffers are allocated using kmalloc? No way at all for user >> space to pass unaligned data? > Most that you will see actually comes from the page allocator. But > the block layer has a dma_alignment limit, and when userspace sends > I/O that is not properly aligned it will be bounce buffered before > it it sent to the driver. That limit is set to L1_CACHE_BYTES on m68k so we're good here. Thanks,     Michael