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[2620:137:e000::1:20]) by mx.google.com with ESMTP id go7-20020a1709070d8700b007b874abc9b6si15654376ejc.790.2022.12.15.04.43.49; Thu, 15 Dec 2022 04:44:13 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@ispras.ru header.s=default header.b=izHOb1pB; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ispras.ru Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229908AbiLOMmn (ORCPT + 99 others); Thu, 15 Dec 2022 07:42:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54958 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229918AbiLOMl2 (ORCPT ); Thu, 15 Dec 2022 07:41:28 -0500 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1FDF12F02E; Thu, 15 Dec 2022 04:40:28 -0800 (PST) Received: from localhost.localdomain (unknown [83.149.199.65]) by mail.ispras.ru (Postfix) with ESMTPSA id 50B4A40737A4; Thu, 15 Dec 2022 12:40:25 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru 50B4A40737A4 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1671108025; bh=qQtYT34Nan6gkSonGyD+MDz80X5GRCr49QTdaEtziC0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=izHOb1pB6ni2VyJVMRfTBCce4P5MOQ6F5K6FKoMkg/PhsZwXw1gEm23Adk0aeQCfu MdBtw9M+EEldUmGHNenxAmItWlGkwnHrHCHlDnASTBXmt4Yljvgg3jMAz45w7/KpBi SewGNmcPEZSIPOSQea3gHks6SIb9i3yQtdsQcXSw= From: Evgeniy Baskov To: Ard Biesheuvel Cc: Evgeniy Baskov , Borislav Petkov , Andy Lutomirski , Dave Hansen , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Alexey Khoroshilov , Peter Jones , "Limonciello, Mario" , joeyli , lvc-project@linuxtesting.org, x86@kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v4 17/26] x86/boot: Reduce size of the DOS stub Date: Thu, 15 Dec 2022 15:38:08 +0300 Message-Id: X-Mailer: git-send-email 2.37.4 In-Reply-To: References: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1752284007290146345?= X-GMAIL-MSGID: =?utf-8?q?1752284007290146345?= This is required to fit more sections in PE section tables, since its size is restricted by zero page located at specific offset after the PE header. Tested-by: Mario Limonciello Tested-by: Peter Jones Signed-off-by: Evgeniy Baskov --- arch/x86/boot/header.S | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S index 9338c68e7413..9fec80bc504b 100644 --- a/arch/x86/boot/header.S +++ b/arch/x86/boot/header.S @@ -59,17 +59,16 @@ start2: cld movw $bugger_off_msg, %si + movw $bugger_off_msg_size, %cx msg_loop: lodsb - andb %al, %al - jz bs_die movb $0xe, %ah movw $7, %bx int $0x10 - jmp msg_loop + decw %cx + jnz msg_loop -bs_die: # Allow the user to press a key, then reboot xorw %ax, %ax int $0x16 @@ -90,10 +89,9 @@ bs_die: .section ".bsdata", "a" bugger_off_msg: - .ascii "Use a boot loader.\r\n" - .ascii "\n" - .ascii "Remove disk and press any key to reboot...\r\n" - .byte 0 + .ascii "Use a boot loader. " + .ascii "Press a key to reboot" + .set bugger_off_msg_size, . - bugger_off_msg #ifdef CONFIG_EFI_STUB pe_header: