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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B13E7C433FE for ; Fri, 8 Oct 2021 10:56:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93EFA61029 for ; Fri, 8 Oct 2021 10:56:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240004AbhJHK6g (ORCPT ); Fri, 8 Oct 2021 06:58:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:43746 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230075AbhJHK6f (ORCPT ); Fri, 8 Oct 2021 06:58:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C56BE60FC1; Fri, 8 Oct 2021 10:56:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1633690600; bh=gPD2dLQZJxejC7F6YoYRsU33148JMVotY1liLeLhOtc=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=ebXdow8iZxUmJdzf5lQNXq1BKus0CpYy4CKGmUc41oJsnsw+S/CB98WZy9F5LJ6Jw y+Z8bC7NN3mbtMGS8I8gtJYT5+Z85/NefqB5AzjaEFAgnTA3qTUJ1Mw4+riYzHunfi C5DlhUCwrUFndrIl16wOOskvhkdKU6xAmMZkUiByc/WJyGDmvWmU0A/lVmgIQGHIfA tIRBd5gQsv9uGwjKENJBrnurGsXQrD47EGgv9FNIqAaNUw7y5xg+EHTjpUb4JJWmrS sn2Ut0ibgH6KUsLin0qA7JxNqnWzoJ8L/xuhf6IrHGIZQJg9wtQI9e0mmU1SMJyPBc IVCWyYLJxCjdw== Date: Fri, 8 Oct 2021 05:56:38 -0500 From: Bjorn Helgaas To: Borislav Petkov Cc: Mika Westerberg , Werner Sembach , benoitg@coeus.ca, bhelgaas@google.com, hpa@zytor.com, juhapekka.heikkila@gmail.com, linux-kernel@vger.kernel.org, mingo@redhat.com, tglx@linutronix.de, x86@kernel.org, linux-pci@vger.kernel.org Subject: Re: [PATCH RESEND] x86/resource: Do not exclude regions that are marked as MMIO in EFI memmap Message-ID: <20211008105638.GA1313587@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [+cc linux-pci] On Fri, Oct 08, 2021 at 11:45:38AM +0200, Borislav Petkov wrote: > On Fri, Oct 08, 2021 at 12:23:31PM +0300, Mika Westerberg wrote: > > Hi, > > > > On Fri, Oct 08, 2021 at 10:55:49AM +0200, Werner Sembach wrote: > > > Is there any update on this matter? Also happens on discrete Thunderbolt 4 chips: > > > https://bugzilla.kernel.org/show_bug.cgi?id=214259 > > > > AFAICT no updates. > > > > @Bjorn, x86 maintainers, > > > > If there are no alternatives can we get this patch merged so that people > > don't need to carry out-of-tree patches to get their systems working? > > Just my 2¢ from briefly skimming over this: > > So this reads yet again as BIOS is to blame but what else is new? > > "All in all, I think we can fix this by modifying > arch_remove_reservations() to check the EFI type as well and if it is > EFI_MEMORY_MAPPED_IO skip the clipping in that case." > > And this like we should trust EFI to mark those regions properly, which > is more of the same but in different color. > > That original commit talks about windoze doing a different allocation > scheme and thus not trusting the untrustworthy firmware anyway and that > sounds like something we should do too. But WTH do I know?! There are a couple other threads reporting similar issues: https://lore.kernel.org/r/20210624095324.34906-1-hui.wang@canonical.com https://lore.kernel.org/r/20211005150956.303707-1-hdegoede@redhat.com I think 4dc2287c1805 ("x86: avoid E820 regions when allocating address space") was a mistake and we should remove that instead of adding more complexity to it. But that requires another approach to fix the issue that 4dc2287c1805 addressed. Bjorn