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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 37FBCC3DA4A for ; Thu, 8 Aug 2024 07:49:49 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.773753.1184191 (Exim 4.92) (envelope-from ) id 1sbxtu-0007b4-UQ; Thu, 08 Aug 2024 07:49:34 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 773753.1184191; Thu, 08 Aug 2024 07:49:34 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sbxtu-0007ax-Pw; Thu, 08 Aug 2024 07:49:34 +0000 Received: by outflank-mailman (input) for mailman id 773753; Thu, 08 Aug 2024 07:49:33 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sbxtt-0007ar-Qa for xen-devel@lists.xenproject.org; Thu, 08 Aug 2024 07:49:33 +0000 Received: from mail-ed1-x52b.google.com (mail-ed1-x52b.google.com [2a00:1450:4864:20::52b]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id bfcb38b7-555a-11ef-bc04-fd08da9f4363; Thu, 08 Aug 2024 09:49:32 +0200 (CEST) Received: by mail-ed1-x52b.google.com with SMTP id 4fb4d7f45d1cf-5b8c2a61386so793775a12.2 for ; Thu, 08 Aug 2024 00:49:32 -0700 (PDT) Received: from [10.156.60.236] (ip-037-024-206-209.um08.pools.vodafone-ip.de. [37.24.206.209]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5bbb2d34a69sm369770a12.70.2024.08.08.00.49.31 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 08 Aug 2024 00:49:31 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: bfcb38b7-555a-11ef-bc04-fd08da9f4363 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1723103372; x=1723708172; darn=lists.xenproject.org; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to; bh=dy+N9f0P7qZ431Chc19ivswpPwLGLpvsx4lm/PF1zX8=; b=bSgJ5NkoB7jyJz6d5WVbaE9zC603pmRHFGfM+qq/JYSQmjYYJgfCI5d8wLVtdnR0B8 BZMDDvgqEHcvAZLBMWJBBtiDU6Jeq+in0hC/19ndifpby03pIXU1qnTJU5GRO68/kG8p II0lixVk6o8Ynn5fcIPcSbDpCK461jTSFZjLhUGXzvRSLY3RvR6BQx8q8LyA4Sez6x/x OxWjz6ar8JC22TfrEfca55M1HvSCmrBGx/hrmD9sKmGGOWdSGJsS4EaSRj1Uq6hS4WSd H+ABW1Ld0nuPUwXg8X2vXjGxLtJHRP5dUGoFIPbpRjZEVVM24jwXjk4msuLRTd1gGqhQ 0skw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723103372; x=1723708172; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=dy+N9f0P7qZ431Chc19ivswpPwLGLpvsx4lm/PF1zX8=; b=ln8XhIyECXbvS5228cPrUYmjiSs0oFEYa3gc1GT9wv8n+WE5Aira/Rx6SDpJqt0ExT P2XJgmHsuSph9LR1/71zLxQmqfhsFL3zYMcOimRlcePbxQXqJ8oSKBqpYQbZYpyRPE+Q OW6n9kZ3r82xeP1+5CP/6GdhvVyxa0ZgzYg0hRApzvjvR0TeVU1Bo7JTgKi4u1HBjfa+ D5GlYjkEjoAFkadzaxBvdDF9CBxsFidE/guad2W3nSy28UPqRaWd13e2tgWNj6a11yVm z+lXPi3jtYHNJNw0FDz6mL3De9XY8d5i1E9mpU9ExGhzh5i06QbaikG4dU6oekL5kPUy NSUA== X-Forwarded-Encrypted: i=1; AJvYcCWuyqfNjleaNOTB3uiNO3i8cfAiUvknkMz2e/86p/3POdIMZgnxfoS3bGcU+tryF8MnccWfCWAaVfsaz/hPkZrR38/gl3hjWGSEINLVypw= X-Gm-Message-State: AOJu0Yx19CDDaaVZX1dnfRUm1JW0vYb/bYd6MiFJMjY8y5pcblpxLnNY gldbQo3QoKoXGA7pyQYMVZVwPhWgUKlI0p/oFiAktaog+z3mTC57T6Sg+1w98Q== X-Google-Smtp-Source: AGHT+IFr/U85rnSIZALNdBIx2UOvzx6GmS6M3+hn2qhYW+AXAGBJm3ri3YpVysrhcusy8Xiajp0TNQ== X-Received: by 2002:a05:6402:1d4d:b0:578:60a6:7c69 with SMTP id 4fb4d7f45d1cf-5bbb23def27mr701785a12.30.1723103371677; Thu, 08 Aug 2024 00:49:31 -0700 (PDT) Message-ID: <7f1e17dd-d105-4f6c-87d3-69f3dca4ab82@suse.com> Date: Thu, 8 Aug 2024 09:49:31 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/5] x86: Fix early output messages in case of EFI To: Alejandro Vallejo , Frediano Ziglio Cc: Andrew Cooper , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , Xen-devel References: <20240807134819.8987-1-alejandro.vallejo@cloud.com> <20240807134819.8987-3-alejandro.vallejo@cloud.com> Content-Language: en-US From: Jan Beulich Autocrypt: addr=jbeulich@suse.com; keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL In-Reply-To: <20240807134819.8987-3-alejandro.vallejo@cloud.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 07.08.2024 15:48, Alejandro Vallejo wrote: > If code is loaded by EFI the loader will relocate the image > under 4GB. This is the MB2 EFI path you're talking about? Since there are two paths, I think this needs clearly separating in all descriptions. If it is the MB2 path, then "relocate" isn't quite correct, I think: Relocations aren't applied in that case, as none are present in xen.gz. I'd rather call this "put at an address below 4G". However, that isn't any different from the non-EFI MB1/2 paths, is it? I feel like I'm missing something here. > This cause offsets in x86 code generated by > sym_offs(SYMBOL) to be relocated too (basically they won't be > offsets from image base). In order to get real offset the > formulae "sym_offs(SYMBOL) - sym_offs(__image_base__)" is > used instead. The main calculations of %esi are, if I'm not mistaken, /* Store Xen image load base address in place accessible for 32-bit code. */ lea __image_base__(%rip),%esi and /* Calculate the load base address. */ call 1f 1: pop %esi sub $sym_offs(1b), %esi i.e. both deliberately %rip-relative to be position-independent. What's wrong with this? There are many more uses of sym_esi(). Why is it only this single one which poses a problem? > Also, in some case %esi register (that should point to > __image_base__ addresss) is not set so compute in all cases. Which "some case" is this? > Code tested forcing failures in the code. > > Signed-off-by: Frediano Ziglio No Fixes: tag? Jan