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 6AF3CC4332F for ; Wed, 9 Nov 2022 10:09:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230029AbiKIKJK (ORCPT ); Wed, 9 Nov 2022 05:09:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229742AbiKIKJI (ORCPT ); Wed, 9 Nov 2022 05:09:08 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E888463B4; Wed, 9 Nov 2022 02:09:07 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8EF7A1FB; Wed, 9 Nov 2022 02:09:13 -0800 (PST) Received: from monolith.localdoman (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9BED83F534; Wed, 9 Nov 2022 02:09:05 -0800 (PST) Date: Wed, 9 Nov 2022 10:08:54 +0000 From: Alexandru Elisei To: Ard Biesheuvel Cc: catalin.marinas@arm.com, will@kernel.org, linux-efi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [Possible BUG] arm64: efi: efi_runtime_fixup_exception() and efi_call_virt_check_flags() both taint the kernel Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, Nov 09, 2022 at 10:07:00AM +0100, Ard Biesheuvel wrote: > On Tue, 8 Nov 2022 at 11:10, Alexandru Elisei wrote: > > > ... > > > > Speaking as an user, I think it would be nice to revert the commit, that's > > how I am running v6.1-rcX kernels on the machine, as updating the firmware > > is not feasible right now. But I realize that I'm not the one maintaining > > the code, so I don't have a strong opinion about it :) And it's better now > > than it was at rc3, when the kernel was panicing. > > > > I sent out a patch yesterday that tweaks the sync exception fixup > handler to only disable the runtime service that triggered the > exception. This means, of course, that you might hit it multiple times > if several runtime service implementations are buggy, but there are > only five or so that we actually use, so that shouldn't make a huge > difference. But it also means a) we don't trigger other code paths > that freak out when a runtime service that was available suddenly goes > away and b) the diagnostics are more useful because we will find out > which other runtime services are broken. > > Could you please test that patch? And for good measure, could you try > something like > > efibootmgr -t 3 > > (as root) to exercise the SetVariable() path as well? Tried booting with the patch applied yesterday, no regression as far as I could tell (still hitting the two add_taint() statements, but that's not what the patch does). I was trying to figure out how I could test that the other runtime services are still working correctly, your suggestion is exactly what I was looking for, thanks. The machine is a shared machine, will test when I get access to it (hopefully later today) and post my findings. Thanks, Alex