From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1adkVz-0001fT-Rc for mharc-grub-devel@gnu.org; Wed, 09 Mar 2016 15:15:27 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37777) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adkVx-0001cr-GO for grub-devel@gnu.org; Wed, 09 Mar 2016 15:15:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1adkVs-0007GC-Aq for grub-devel@gnu.org; Wed, 09 Mar 2016 15:15:25 -0500 Received: from mail-lb0-x236.google.com ([2a00:1450:4010:c04::236]:35128) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adkVr-0007Fy-W3 for grub-devel@gnu.org; Wed, 09 Mar 2016 15:15:20 -0500 Received: by mail-lb0-x236.google.com with SMTP id bc4so81966554lbc.2 for ; Wed, 09 Mar 2016 12:15:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=O3HWZ9sFXjVXKQxgNEZms3vA9eatLAbiKGbr3R8x3rc=; b=ALgnnLNIgcN2XtVIeVbvUZt82CmtvoPmxofXuLgCHKT47rTZE2xI7UR1dlqx9lZazJ oy9Pd44j+LHEyjH+lySh23PKjIGH/DfoqD1vYHhrOP96XC+m3yTyhS9IzOPS72MMOZMq WqPQzeYedBLoIabdA2vx+n69LSC/3hHLFjCp5rgoK0KbPGL9w+V/wcB3wNBhUU7GbKqA SZHW6oFxyt9qDpfafru7ssJggf+xKUZPyDL3xLMaKtQdjB/QgJGc1SCr/iuZf0xZQm4y OM8aX9dQIyPNp1GYtBVWGY1KaUAEy3o8AgpgTCPBnhhUcN1qRQmKGYDsZM2/hCT+GSlc QbIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=O3HWZ9sFXjVXKQxgNEZms3vA9eatLAbiKGbr3R8x3rc=; b=L2LkQRufvkH7W2RneCs1V3hc7ePwbVIdMqU1pdgZNvplEhdayRI5ZqzYcupQQ+j2U/ Ex9YG9hzod0ryBf0l/ydOBzKie+AIeGXkhzzfh2HDxHgF4Ed3QwH7q83gqrly3szr48y 6LdkxADjy3T3aOAbJyqkEsd4BfvmsKj0K2P6h0wp3X0mE8qdp4v4eFMPjVaPfAPTplia vbJf6rSDmPb+thrmg4oEf6VOfB6+YEvK5yGsfNVFCNiomKNvp9YwCtvAqoEgD1mq7aio ulDEMAmBySEM7MBmFpJR08gtYitM4ytrIMysStO/Bkw94PQ/z3YgX/zobzLEMjDCMr7E xMJQ== X-Gm-Message-State: AD7BkJLzuplb9WH9jXu3Nd4ECIal+uSg7GIVCkXypcPJ4ZNUMNuOBsEPw2qJOmdk3Si2Lw== X-Received: by 10.112.14.39 with SMTP id m7mr56920lbc.20.1457554519203; Wed, 09 Mar 2016 12:15:19 -0800 (PST) Received: from [192.168.1.42] (ppp109-252-76-159.pppoe.spdop.ru. [109.252.76.159]) by smtp.gmail.com with ESMTPSA id ai2sm27281lbc.46.2016.03.09.12.15.17 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 09 Mar 2016 12:15:18 -0800 (PST) Subject: Linux loader EFI handover (was: Bugs and tasks for 2.02[~rc1]) To: Matt Fleming References: <20160307190016.GA13163@redhat.com> <56DDE5B0.6080002@gmail.com> <56DDEB3D.4010505@gmail.com> <20160307211958.GF13163@redhat.com> <56DDF2AA.3010504@gmail.com> <20160307220132.GI13163@redhat.com> <20160308034010.GA19551@linux-dsax.tai.apac.novell.com> <56DE5BBF.5050108@gmail.com> <20160309151824.GA15775@codeblueprint.co.uk> From: Andrei Borzenkov X-Enigmail-Draft-Status: N1110 Message-ID: <56E08454.4020107@gmail.com> Date: Wed, 9 Mar 2016 23:15:16 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <20160309151824.GA15775@codeblueprint.co.uk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a00:1450:4010:c04::236 Cc: The development of GNU GRUB , Colin Watson , Vladimir 'phcoder' Serbinenko X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list Reply-To: The development of GNU GRUB List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Mar 2016 20:15:26 -0000 09.03.2016 18:18, Matt Fleming пишет: > On Tue, 08 Mar, at 07:57:35AM, Andrei Borzenkov wrote: >>>> - 64-bit kernel on 32-bit platform like Baytrail can't work >> >> Do you mean "32 bit EFI"? If yes, why is it a problem? > > The biggest issue is that there's no way right now for a boot loader > to tell the kernel that it needs to use a translation layer when > calling EFI services (we refer to this as the "thunk" layer in the > kernel) without going via the EFI handover protocol. > > Obviously this could be achieved by writing the required code for GRUB > but it would be largely duplicated from the existing code EFI boot > stub code in the kernel. I don't think it's worth the effort. > That sounds like this should be supported irrespectively of secure boot then. > The kernel figures out when to use the thunk layer by taking note of > which EFI handover offset entry point the boot loader entered from, we > include both a 32-bit and 64-bit entry point when CONFIG_EFI_MIXED is > enabled. > OK, looking at linuxefi patch, the only real difference from normal linux loader is that it restricts memory allocations to below 1G. Is it kernel requirement? What to do if kernel is compiled without CONFIG_EFI_MIXED support? Should we fall back to traditional handover without calling into EFI stub or fail load completely?