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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH 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 D86A7C46464 for ; Thu, 9 Aug 2018 21:07:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 87E1221EFC for ; Thu, 9 Aug 2018 21:07:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="RmAByoZ3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 87E1221EFC Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727529AbeHIXeW (ORCPT ); Thu, 9 Aug 2018 19:34:22 -0400 Received: from mail-yw1-f67.google.com ([209.85.161.67]:38642 "EHLO mail-yw1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727198AbeHIXeW (ORCPT ); Thu, 9 Aug 2018 19:34:22 -0400 Received: by mail-yw1-f67.google.com with SMTP id r3-v6so6626286ywc.5 for ; Thu, 09 Aug 2018 14:07:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=FmgkmGYPVQMjcc62pVV/RXIRRnmQP+YI7wT1PZOI4AE=; b=RmAByoZ3VB2R06qKvmM0wF9e6LWJsK37EL46qHsJOA6XFXzTJJGO3+TwGRFBy3NAfx AsidcPRx6xB7ajkGZ3Em5SGfAn8I85GzW03rKUJZjZHkK3y4xBfr6WnhtmuMwcmDdm0v MvdNdXNI2aHzKACUOSyheqovPxobjn+mQyA9A= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=FmgkmGYPVQMjcc62pVV/RXIRRnmQP+YI7wT1PZOI4AE=; b=DIgdjUtD//3OTZDQnV3hUSRVQ/9yZJ6tzY4CG/e0o6oGlZ+q1ZKC+cjjtU8vn9YcoJ QWNfkeYjn6QrlkYiKGtNZxvnPiF/cV22xAw5F4hlSIt+h1ewJtp5VgH6XcSTaHXZyiQh zSTZo3Kq2pNFQFuvsayO6EDep+t9QB97r8Zcp2BXa/sP38NiwgcAT2Ya8TjiaeixoRUn 4kqKhp4bsujnP5+AHZ8H5EU+rrwJJFPTlfi+A1CIGeaRE+605Jt4oXfO/aZ0GLK3W3AX aaJqrLFB0bb3V/rPk4GShY4F6UzO4T+gxXk686QY37mT0t5qq6oMM+s2kBtMY0OxhvXz 6iaQ== X-Gm-Message-State: AOUpUlFvlmubJN3PvcgV9IJg9LJIFH9Muh1Lpvd8+FVkw9wEcLQg4QY6 R9+VOjKYUiMm5yw/7TtVrmUMoe3SC/DhGE3P+w0fukx9 X-Google-Smtp-Source: AA+uWPwAnjrFL1z0Pw9dr6H5TMB4o85IDkNabGlia7WN7PZaO20t0KjTePpZzhNcu2IRnsfoB4tykA1C7YuKAz42S/A= X-Received: by 2002:ab0:2089:: with SMTP id r9-v6mr2575138uak.71.1533848865192; Thu, 09 Aug 2018 14:07:45 -0700 (PDT) MIME-Version: 1.0 References: <20180809171722.144325-1-swboyd@chromium.org> <20180809171722.144325-8-swboyd@chromium.org> In-Reply-To: <20180809171722.144325-8-swboyd@chromium.org> From: Julius Werner Date: Thu, 9 Aug 2018 14:07:31 -0700 Message-ID: Subject: Re: [PATCH v3 7/7] firmware: coreboot: Request table region for exclusive access To: swboyd@chromium.org Cc: Greg Kroah-Hartman , LKML , Wei-Ning Huang , Julius Werner , Brian Norris , samuel@sholland.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Archived-At: List-Archive: List-Post: On Thu, Aug 9, 2018 at 10:17 AM Stephen Boyd wrote: > > Call request_mem_region() on the entire coreboot table to make sure > other devices don't attempt to map the coreboot table in their drivers. > If drivers need that support, it would be better to provide bus APIs > they can use to do that through the mapping created in this file. > Does this prevent userspace from mapping this region via /dev/mem? If so, let's please not do it to not break compatibility with existing tools. (I guess an alternative would be to rewrite 'cbmem' to use /sys/bus/coreboot/devices if available to get its coreboot table information. But we'd still need to maintain the old path for backwards compatibility anyway, so that would really just make it more complicated.)