From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Fri, 05 Jan 2024 11:42:39 +0100 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1rLhex-004cHV-1T for lore@lore.pengutronix.de; Fri, 05 Jan 2024 11:42:39 +0100 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1rLhew-0004gg-LS for lore@pengutronix.de; Fri, 05 Jan 2024 11:42:39 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Cc:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=s/qgSuQnFYdFlsh96SjHLOpXV+iyfB589LRhVNgWuAM=; b=vxJnh6f2bHSGfBVKyJvg5QBGmx s5OtxfjT/y/fgVOUjNpYbJ9f5DxAoElyyxAcL+eDUlQpDIKTnhglqMTD9zYk4aPqlshZkRSq2oKRS qtswfUJ1ZsngBk7aESweYzetVSnYuIqu86sjRsfj2FTQoGI6mnGByDSk5hNkFcKfSfYcy1kcWrM0I xoIU7nK6orME0Bz51uOwbAQNeCCVkqTrOdWbHQxpCBAOIKhJnsMk57oT3xoGD8AJqCupCheDjgfLG DrmK2alMaGHGOA4f2Yt9oNgK9zF0lDx5m4QnAQ9Ws4vF2ysGgTcP42zF1vHrvVxd7d0xKHQpjyFPD FMPHVZVw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rLhde-00GZyP-1e; Fri, 05 Jan 2024 10:41:18 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rLhda-00GZxa-2Q for barebox@lists.infradead.org; Fri, 05 Jan 2024 10:41:16 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1rLhdX-0004QC-2a for barebox@lists.infradead.org; Fri, 05 Jan 2024 11:41:11 +0100 Message-ID: Date: Fri, 5 Jan 2024 11:41:09 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-US To: barebox@lists.infradead.org References: <20240103181312.409668-1-a.fatoum@pengutronix.de> <20240103181312.409668-60-a.fatoum@pengutronix.de> <3c4fc4ee-a4fe-44e5-a4c5-7a8f086a1124@pengutronix.de> From: Ahmad Fatoum In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240105_024114_789112_7B810081 X-CRM114-Status: GOOD ( 33.97 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-6.4 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 059/112] efi: payload: init: restrict barebox mem to first 1G only on x86 X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) On 05.01.24 10:31, Michael Olbrich wrote: > Hi, > > On Fri, Jan 05, 2024 at 10:14:33AM +0100, Ahmad Fatoum wrote: >> On 04.01.24 19:10, Michael Olbrich wrote: >>> On Thu, Jan 04, 2024 at 12:17:12PM +0100, Ahmad Fatoum wrote: >>>> On 03.01.24 19:58, Michael Olbrich wrote: >>>>> On Wed, Jan 03, 2024 at 07:12:19PM +0100, Ahmad Fatoum wrote: >>>>>> When run as EFI payload, barebox will not have full access to DRAM and will >>>>>> have to ask the EFI firmware for memory. It does so once at the beginning >>>>>> and since commit 356aaef5a37d ("efi: improve malloc pool allocation"), >>>>>> the buffer was always placed beneath the 1G boundary. >>>>>> >>>>>> Aforementioned commit didn't elaborate why a maximum of 1G in particular >>>>>> was chosen. Anyways, non-PC architectures have different memory maps, so >>>>>> a 1G limit doesn't make sense there. Therefore restrict the limit to >>>>>> ARCH_X86. On non-x86, we allow the memory pages to be located anywhere. >>>>> >>>>> The 1G is somewhat arbitrary but if you don't restrict the memory to 32bit, >>>>> then loading the kernel may fail: The addresses in "struct >>>>> linux_kernel_header" are only 32bit. So if you impose no restrictions at >>>>> all, then this memory cannot be used for the kernel and initrd. >>>> >>>> The limit for x86 remains at 1G. It's only for other architectures, that we >>>> remove the limit. I suspect that other architectures won't have this kind >>>> of problems though , because they would boot the kernel image via EFI load >>>> and start image boot services, where the EFI firmware takes care to layout >>>> the boot artifacts. >>>> >>>> Once we have that in place, we could even use it on x86 instead of >>>> using struct linux_kernel_header, but I haven't investigated this yet. >>> >>> How do you load the initrd via EFI? As far as I know, that only works as a >>> filename in the EFI boot partition. >> >> This seems to be relaxed in newer kernels, see >> https://lore.kernel.org/linux-efi/20200207202637.GA3464906@rani.riverdale.lan/T/ > > It's not quite clear to me how that works, but from what I can tell, > requires support from the firmware and barebox needs to use it. So that > does not help here. > You need to either disable the legacy handler to avoid arbitrary failures > or explicitly allocate the initrd memory from efi with the restriction to > <4G. The legacy handler wouldn't apply to other architectures: - The Kernel images for ARM64 and RISC-V have different more-specific filetypes than filetype_exe - The Linux kernel header check will probabaly fail for every format that's not x86 Cheers, Ahmad > > Michael > >>> That was the reason for implementing >>> the "legacy" boot mode. And what about the device-tree? >> >> There is an EFI config table for FDT (DEVICE_TREE_GUID in Linux code). barebox >> as EFI loader can use it to provide its own DT. I have to check what's the cleanest >> way for barebox as EFI payload to provide a different DT, but I hope there is a way >> without barebox as EFI payload having to manipulate the device tree itself. >> >> Cheers, >> Ahmad >> >>> >>> Michael >>> >>>>>> This can break PCI drivers on systems that so far assumed barebox memory >>>>>> is located in the first 4G, but that's ok. That code will need to be >>>>>> fixed eventually anyway. >>>>>> >>>>>> Cc: Michael Olbrich >>>>>> Signed-off-by: Ahmad Fatoum >>>>>> --- >>>>>> efi/payload/init.c | 2 +- >>>>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>>>> >>>>>> diff --git a/efi/payload/init.c b/efi/payload/init.c >>>>>> index 4b612e61afb3..0c2f38e9c86a 100644 >>>>>> --- a/efi/payload/init.c >>>>>> +++ b/efi/payload/init.c >>>>>> @@ -292,7 +292,7 @@ void efi_main(efi_handle_t image, struct efi_system_table *sys_table) >>>>>> BS->handle_protocol(efi_loaded_image->device_handle, >>>>>> &efi_device_path_protocol_guid, (void **)&efi_device_path); >>>>>> >>>>>> - mem = 0x3fffffff; >>>>>> + mem = IS_ENABLED(CONFIG_X86) ? 0x3fffffff : ~0ULL; >>>>>> for (memsize = SZ_256M; memsize >= SZ_8M; memsize /= 2) { >>>>>> efiret = BS->allocate_pages(EFI_ALLOCATE_MAX_ADDRESS, >>>>>> EFI_LOADER_DATA, >>>>>> -- >>>>>> 2.39.2 >>>>>> >>>>>> >>>>> >>>> >>>> -- >>>> Pengutronix e.K. | | >>>> Steuerwalder Str. 21 | http://www.pengutronix.de/ | >>>> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | >>>> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | >>>> >>>> >>> >> >> -- >> Pengutronix e.K. | | >> Steuerwalder Str. 21 | http://www.pengutronix.de/ | >> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | >> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | >> >> > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |