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 X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A160EC433E4 for ; Sat, 18 Jul 2020 14:38:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7EC832076A for ; Sat, 18 Jul 2020 14:38:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SG5qqxEv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727883AbgGROiu (ORCPT ); Sat, 18 Jul 2020 10:38:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40370 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726611AbgGROis (ORCPT ); Sat, 18 Jul 2020 10:38:48 -0400 Received: from mail-io1-xd42.google.com (mail-io1-xd42.google.com [IPv6:2607:f8b0:4864:20::d42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFFFCC0619D2 for ; Sat, 18 Jul 2020 07:38:47 -0700 (PDT) Received: by mail-io1-xd42.google.com with SMTP id v8so13312107iox.2 for ; Sat, 18 Jul 2020 07:38:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2bE7ryY5bmKmNgC6eIa/UyE6X2gMyGEMpAXbppuSg5s=; b=SG5qqxEv/bGbPPNqoo7521htEX4rcqNPDp07njON8/cMZx0JcU2vERb7Kd2mvsmF/q f3R7uqwVmMM5+Gna/QHkGOKjc9JJP5XZoiyaOzM0YxgpMw2EBBrrRvSfBi/T/Kj2WY1D 4525U0FQutq7jlRpU/+0wFF2OJ8SeT63omQAdAhR79QqXcT48yi6vm3PFHO285HL2k5q IxkcvFWpmeFWBnqIfJ/c7ExHhM3rI9Y1J7xlDFyl3JcBTuLgTS2r80leHkvhM4vGuefr AaBQFXkD/GRjTK7lB/wsACxRXQ/geRxys8RzwnzFyTl3FzJcWJVoQo8pMbTL/dlZvNwS 3ChQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2bE7ryY5bmKmNgC6eIa/UyE6X2gMyGEMpAXbppuSg5s=; b=UZiik9YMpDyRUGvJmgL6Us+qcOezkec3xRwRm4na4llmHxnkqcPHNs9zQuymCQlw4X STlDEE1DdYYEXlcA+v2kRbv+djYzB/ft/RePQysmCwePQI9gktlUNah1SjS1dYBpkZ0m t8A25drvHA6luzaJ4EbOgTtPMWNa3uyAYTNZVWyf7nmgZ9Aq1vpBlC9OO60lMLSDhkzi xp8rHnM1wGStqHwAE5cRATAk2jZatvcDUcV9dIyfOu677tkrk7jHc+i1i+QcSIgeFqbZ s0W/l6Ofxmvp3ttHPVRzhQNqlkWd6f5K+hNaMVnW9BsyNkQwGMxhM5SsAeUsR3qhd5EY BKlg== X-Gm-Message-State: AOAM530ZT4GlumI0mqMoWdnULeQkNW7zxJdrlW8mpji7lcQZ0laW5Eom udXM/6C1Asjvhn6Hqih/vJKLhpE= X-Google-Smtp-Source: ABdhPJyG7ikvEwxq1esi7aQLgsQDtfVaQXlzfytabaXHyjZ7SgEi/aVpBv46vIbg3G8ZAWhOAHoeGg== X-Received: by 2002:a02:70d6:: with SMTP id f205mr16344131jac.5.1595083127172; Sat, 18 Jul 2020 07:38:47 -0700 (PDT) Received: from localhost.localdomain (174-084-153-250.res.spectrum.com. [174.84.153.250]) by smtp.gmail.com with ESMTPSA id 5sm5888610ion.7.2020.07.18.07.38.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 18 Jul 2020 07:38:46 -0700 (PDT) From: Brian Gerst To: linux-kernel@vger.kernel.org, x86@kernel.org Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , Andy Lutomirski , Brian Gerst Subject: [PATCH 2/3] x86-32: Remove SEP test for SYSEXIT Date: Sat, 18 Jul 2020 10:38:38 -0400 Message-Id: <20200718143839.194960-3-brgerst@gmail.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200718143839.194960-1-brgerst@gmail.com> References: <20200718143839.194960-1-brgerst@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org SEP must be present in order for do_fast_syscall_32() to be called on native 32-bit. Therefore the check here is redundant. Signed-off-by: Brian Gerst --- arch/x86/entry/common.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 9e01445f6679c..bdb4c15b8610e 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -587,8 +587,7 @@ __visible noinstr long do_fast_syscall_32(struct pt_regs *regs) * We don't allow syscalls at all from VM86 mode, but we still * need to check VM, because we might be returning from sys_vm86. */ - return static_cpu_has(X86_FEATURE_SEP) && - regs->cs == __USER_CS && regs->ss == __USER_DS && + return regs->cs == __USER_CS && regs->ss == __USER_DS && regs->ip == landing_pad && (regs->flags & (X86_EFLAGS_RF | X86_EFLAGS_TF | X86_EFLAGS_VM)) == 0; #endif -- 2.26.2