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 740BCC433F5 for ; Sun, 31 Oct 2021 12:05:39 +0000 (UTC) Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7A6F260D07 for ; Sun, 31 Oct 2021 12:05:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7A6F260D07 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=walle.cc Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.denx.de Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id C96678187B; Sun, 31 Oct 2021 13:05:34 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=none (p=none dis=none) header.from=walle.cc Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Authentication-Results: phobos.denx.de; dkim=pass (1024-bit key; secure) header.d=walle.cc header.i=@walle.cc header.b="CH5/TXVb"; dkim-atps=neutral Received: by phobos.denx.de (Postfix, from userid 109) id 70FA482BC0; Sun, 31 Oct 2021 13:05:32 +0100 (CET) Received: from ssl.serverraum.org (ssl.serverraum.org [176.9.125.105]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by phobos.denx.de (Postfix) with ESMTPS id A6C22815A8 for ; Sun, 31 Oct 2021 13:05:04 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=none (p=none dis=none) header.from=walle.cc Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=michael@walle.cc Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 7185322236; Sun, 31 Oct 2021 13:04:40 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1635681880; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=sC+9MiPJi7yXeKXC+jkJtT1iWRxgEw2vZwCpj9km1ig=; b=CH5/TXVbH60u1lnDOHD8zlY3Dd71nYwR6wecC/vLwkEppTY5iRHMCPhoRtYTnAjKfQVmC+ BfAXiV23z1USYRPEdEsHjtTNDt99/NuOiVROi20Io7FlhpGo5a/tWKSNxzTdRnye2Z5M6I ZK1uWJIQrswSWfasiv7ZtsGnmjO+vbg= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Sun, 31 Oct 2021 13:04:40 +0100 From: Michael Walle To: Mark Kettenis Cc: u-boot@lists.denx.de Subject: Re: (overlapping) lmb allocations during boot In-Reply-To: References: <63a9d684653e3d19e621a8d978f44113@walle.cc> User-Agent: Roundcube Webmail/1.4.11 Message-ID: <1f9f258db11b21bfd7db4fe1eef785eb@walle.cc> X-Sender: michael@walle.cc X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.34 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.2 at phobos.denx.de X-Virus-Status: Clean Am 2021-10-31 12:44, schrieb Mark Kettenis: >> Date: Sun, 31 Oct 2021 11:43:38 +0100 >> From: Michael Walle >> >> Hi, >> >> I sometimes see a corrupted initrd during kernel boot on my board >> (kontron_sl28). Debugging showed that in this case the spin table >> for the secondary CPUs overlaps with the lmb initrd allocations >> (initrd_high is set). >> >> I had a look at how the fdt and initrd are relocated (if enabled). In >> summary, they use lmb_alloc() which will first add all available >> memory >> and then carve out reserved regions. There are calls for arch >> (arch_lmb_reserve()) and board (board_lmb_reserve()) callbacks. The >> interesting thing is that, there is also code to carve out any >> reserved regions which were added to the fdt earlier >> (boot_fdt_add_mem_rsv_regions()). The problem here is, that the DT >> fixups, >> which might add the reserved regions are called just before jumping to >> linux. Thus both the allocation for the fdt (if fdt_high is set) and >> the ramdisk (if initrd_high is set) will ignore any reserved memory >> regions. >> >> Unfortunately, I don't see any good way to fix this. You'd need all >> the >> DT fixups before we can initialize the lmb. Also, I don't know if this >> will affect any other areas; probably I'm the only one, who reserves >> an >> area which is outside of the u-boot code and data segment. >> >> A hackish way would be to carve out the spin_table code in >> board_lmb_reserve(). But meh.. > > The spin table is embedded in the u-boot binary itself isn't it? But > the memory occupied by the u-boot should already be reserved... Yes it is. As long as it doen't overlap with the 64k EFI code page. See below. > Unless CONFIG_EFI_LOADER is defined. Then it relocates the spin table > to memory allocated using efi_allocate_pages(). But that function > only looks at the EFI memory map to figure out what memory is > available. So I suspect that it might hand out the same memory as > lmb_alloc(). It all looks a bit broken to me... Yes, that is actually my code ;) The kontron_sl28 is the only board which uses spin tables as far as I know. It doesn't support PSCI; at least if you don't load a bl31 TF-A. Therefore, for SMP it uses spin tables. The relocation code work arounds a problem with the reserved EFI code, see [1]. And yes, it actually is broken. But so might be every code which is using the efi_allocate_pages(), no? LMB isn't global, but is just initialized at different places. Like before a linux kernel is booted or when you load a file (?). And everytime the whole memory is added, and then different regions are carved out (see above). > Does your target end up with CONFIG_EFI_LOADER defined? Yes ;) -michael [1] https://lore.kernel.org/u-boot/20200601195336.3237-1-michael@walle.cc/