Path: csiph.com!goblin3!goblin.stu.neva.ru!news.roellig-ltd.de!open-news-network.org!weretis.net!feeder4.news.weretis.net!news.mixmin.net!aioe.org!bofh.it!news.nic.it!robomod From: Alexander Kuleshov Newsgroups: linux.kernel Subject: [RFC PATCH] x86/head_64.S: remove redundant check that kernel address is 2M aligned Date: Fri, 22 Jan 2016 19:20:01 +0100 Message-ID: X-Original-To: Thomas Gleixner Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id; bh=fbYNKcO7ygWPX+xrcW9qG243Gn/2WzlvstXi7x/11/k=; b=P9LIbM9osoWhZQ0BMxY2BIQ7OMQYbgPrcYzcDC2b0boh5wKGxLBgnYGjpzLykMnsjv p2Fzk49PI8BT4/GYPfGXWdKYI5158jzBT6TXMA5C4mxtN7DvZCtUkpY5QLHrtYaUvCap 7IqHo++fTw771VBwaJXEw+iRF6ILAW+OAXH7bhxBbcgYy0imDAdRebxA1LDl7ILw5n41 8vWkTxnWwK98OIj50cHPJuC4FUBukdU3rCBFE+jbOhtMTnjkLYU0HdvhMUC7ACLi/LJA Zb3imc6hZrt70aHtAS5SqplNIl8qXpQclvrG+M1C+6YUB3p4T+6s55tmXPQhQVry5LYb Ck+w== X-Google-Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=fbYNKcO7ygWPX+xrcW9qG243Gn/2WzlvstXi7x/11/k=; b=G/ij3Qz5FxonBWawWkZOgq7yBgApPNRUjYMvhhUPUOuVNQTRYPfRXL7SpPEtDet+YK 4uVeXPaueeoFemLE3aGbsjw+qA6tFJB6j8kc6je+uX4AVvR2alAsHYCXlLJWds87fuzk qrRN1vJb/BKB92o4kInX2A13v42NY2Zh5Nob8eFDU4G6/WarworaLeRAE9XqvQHTN2WS hRyfMGFs6F23W0EAL8zebqAwnmkJsNlhRoivHzqp8ZMHz9Cxu3vzH3cxJ6xXGiyjAfdm VwoBfSSQfXNnlvVHvqYwETnzhNSmi3scrpSBviWKtvIUS4FSSW3TUUMJQx5xD9cuC/8e L4eA== X-Gm-Message-State: AG10YOTnH2c68Fx0/E3Nl+2KdP4EKXuBD94yeDr2vhwHNkaUOK2yuOa9rbqweg1XaU6pRQ== X-Received: by 10.25.136.214 with SMTP id k205mr1471355lfd.39.1453486612319; Fri, 22 Jan 2016 10:16:52 -0800 (PST) X-Mailer: git-send-email 2.7.0.25.gfc10eb5 Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 30 Organization: linux.* mail to news gateway X-Original-Cc: Ingo Molnar , "H . Peter Anvin" , Andy Lutomirski , Borislav Petkov , Denys Vlasenko , Andrey Ryabinin , x86@kernel.org, linux-kernel@vger.kernel.org, Alexander Kuleshov X-Original-Date: Sat, 23 Jan 2016 00:13:12 +0600 X-Original-Message-ID: <1453486392-10289-1-git-send-email-kuleshovmail@gmail.com> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1315189 We check that the base address of the kernel is 2M aligned in the arch/x86/kernel/head_65.S right after jump to the decompressed kernel. But we already have a check in the decompress_kernel() which validates that kernel location is MIN_KERNEL_ALIGN aligned which is 2M too for x86_64. Signed-off-by: Alexander Kuleshov --- arch/x86/kernel/head_64.S | 6 ------ 1 file changed, 6 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index ffdc0e8..4967cba 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -75,12 +75,6 @@ startup_64: leaq _text(%rip), %rbp subq $_text - __START_KERNEL_map, %rbp - /* Is the address not 2M aligned? */ - movq %rbp, %rax - andl $~PMD_PAGE_MASK, %eax - testl %eax, %eax - jnz bad_address - /* * Is the address too large? */ -- 2.7.0.25.gfc10eb5