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=-4.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 9D0F8C433E0 for ; Mon, 3 Aug 2020 13:18:47 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 6AEFA206D7 for ; Mon, 3 Aug 2020 13:18:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="eO9yqVX4"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=eclypsium.com header.i=@eclypsium.com header.b="Pb+02f+l" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6AEFA206D7 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=eclypsium.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From:In-Reply-To: References:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7oVtOz6Q14wQle+ccaC0RaTxSDVyIKMLG1JgamvvvBA=; b=eO9yqVX4NhFU7x+45CG87+P33 wJ7K6A215OaBE1jZH86sxNy8XIailrfQX3vJLWHOKJmC7TD+o8AvbFLz6DK1f2jpCWYROrrCV1jWG LX/P5Avdt/gj4dE3eXt/jtfiVrW1mW7Bb+4iVV4GDyZ+BI61aIlii+J7Kf7GrIeBZGyrUV/Xjyh1a 4OUJzsTV1T6KV30OGK2Lepp+g8cq0jOQD32BZ+yPlJ/w3o1wbyPFj6QF1e6mQRdAedXbazaA2xQi5 aiclU0i3x+6mqisdFTz3Kcks2lIoOXl9SpDXusg99z//xvfwti1m6pI6cC8mSZgpIQ5AVY07fk9GP EcvjgzTcg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k2aM4-0002c6-CD; Mon, 03 Aug 2020 13:18:16 +0000 Received: from mail-qk1-x744.google.com ([2607:f8b0:4864:20::744]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k2aM1-0002bQ-7n for linux-mtd@lists.infradead.org; Mon, 03 Aug 2020 13:18:14 +0000 Received: by mail-qk1-x744.google.com with SMTP id x69so35058365qkb.1 for ; Mon, 03 Aug 2020 06:18:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=eclypsium.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ZcGSsHeP5e+40JMga9CZxbgjB55gpH983rZr/StcFAo=; b=Pb+02f+lDwuPKfIgC7YpTTAr50AWdc6glnECFDurbxg4pSS3SjHUTXxXX3wN+Hprr/ n1J0MOvStjeeMjEG19RtlI2OLIfbaif/JPVlVcVjlup8AWCPXVek+TkWEHvodvhoh+q4 X/tQfzPDPAVwtECIcLoMry+52bo6Ms36g536J0ASbYh1mV+fjLxA3etISDxPvxFnqxAO HVvyLWrRyJKHQu4A3ic+p9o3Na0Aw22MdRVvJJwAhNXXLW34+8BQz0QDdVfRscAm51gE sjqCGCvG9FBMpyFF+fQWOpvSutGu+5NNFokSkYcXZ/VNEe47VCVNNrcy8DYPqs8hwUOk U+Ng== 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=ZcGSsHeP5e+40JMga9CZxbgjB55gpH983rZr/StcFAo=; b=cG29dRDWSy+KIVWd/dr2l3SQkO1a9xGzCu39ub6Qd6CFcB+VNaNCFD8M6kvQJZZ5J7 TeMa/dprJz/LlwYtjnPbUsKhhh0/dLkRG1ld8iCt4SKqh1epnBlOUrX9CqPC1A8Cge06 HaD+wyXGZQyyLLj+N+Hxr53lHtJ7mCldmFkFP2k7pzGv4MxcTAHL/byjHgE6H5WfmL5f akR3KMuhWBYjPDAf0zPEDG9Z2hejd5VdkfZEqdbF04VbCfcuR6GPx4RHAQtXHwy/Ny+7 oCdLSB+yQvkO04BcNLNw6Y+d0n+5vCI1K1n3VIQMvB2UB87tHf6f2jOH4Hi/ozDqpLwV b8nw== X-Gm-Message-State: AOAM533H/V6VCV2ZrLLqUM/GKkp54WLSijrH0Fs5Q70UXgVDdbECvDPg etwg5sgnsmY4LYvExO5tGzi9ChO6QcGJvnxfB2Dh27mE X-Google-Smtp-Source: ABdhPJzV2OSdSL38md1inZlV4Js8tyGX4S/yZviIwNc+fjhKkgbH+HYlmRqOKQnU9+4FgORa4568bHLOB4JkhcQMMe8= X-Received: by 2002:a37:278d:: with SMTP id n135mr15719786qkn.486.1596460691093; Mon, 03 Aug 2020 06:18:11 -0700 (PDT) MIME-Version: 1.0 References: <20200724212853.11601-1-daniel.gutson@eclypsium.com> <20200803095720.GC1375436@lahna.fi.intel.com> <20200803102711.GK1375436@lahna.fi.intel.com> <20200803130532.GY1375436@lahna.fi.intel.com> In-Reply-To: <20200803130532.GY1375436@lahna.fi.intel.com> From: Daniel Gutson Date: Mon, 3 Aug 2020 10:17:59 -0300 Message-ID: Subject: Re: [PATCH] Module argument to control whether intel-spi-pci attempts to turn the SPI flash chip writeable To: Mika Westerberg X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200803_091813_381939_03827EAA X-CRM114-Status: GOOD ( 22.23 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vignesh Raghavendra , Arnd Bergmann , Boris Brezillon , Richard Weinberger , Richard Hughes , linux-kernel , Greg Kroah-Hartman , linux-mtd , Tudor Ambarus , Miquel Raynal , Alex Bazhaniuk Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Mon, Aug 3, 2020 at 10:06 AM Mika Westerberg wrote: > > On Mon, Aug 03, 2020 at 09:58:23AM -0300, Daniel Gutson wrote: > > On Mon, Aug 3, 2020 at 7:27 AM Mika Westerberg > > wrote: > > > > > > On Mon, Aug 03, 2020 at 11:18:12AM +0100, Richard Hughes wrote: > > > > On Mon, 3 Aug 2020 at 10:57, Mika Westerberg > > > > wrote: > > > > > I think instead of this we should simply make it so that the driver > > > > > never tries to make the chip writable. > > > > > > > > I think this is a good idea, but I wasn't sure if it was an acceptable > > > > behaviour change. Should the driver still try to set BCR_WPD when > > > > writing an image (i.e. defer the setting of write enable until later), > > > > or just not set the BCR register at all? I think your last comment was > > > > the latter, but wanted to check. > > > > > > I would say not set it at all. I think it was (my) mistake to set it in > > > the first place. > > > > Do you want me to remove the module parameter from intel-spi too and > > do the same? > > No, I think that should still be left there. Then by default it is > read-only and you can only enable writing if the BIOS allows it and that > the user actually requested it. OK. Patch heading your way in 1h. -- Daniel Gutson Argentina Site Director Enginieering Director Eclypsium Below The Surface: Get the latest threat research and insights on firmware and supply chain threats from the research team at Eclypsium. https://eclypsium.com/research/#threatreport ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/