From patchwork Thu May 23 09:06:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 164949 Delivered-To: patch@linaro.org Received: by 2002:a92:9e1a:0:0:0:0:0 with SMTP id q26csp1913724ili; Thu, 23 May 2019 02:06:40 -0700 (PDT) X-Google-Smtp-Source: APXvYqz1slxEA2QITBiZsiTyI1jUpL5hRR9Ub3RWF5D7gkftTulOpoWUkGVtbAT6Sq9dOwFCVSSk X-Received: by 2002:a63:a449:: with SMTP id c9mr7016727pgp.149.1558602400004; Thu, 23 May 2019 02:06:40 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1558602399; cv=none; d=google.com; s=arc-20160816; b=mU+MVILQml/n8eebevKJ+AU1oXiDVHjgzSct6fvNEoUfmVBrheJTMOJ6GwcEqtTyhX T+htMy5t84b8yEWGk69cYlkWu/fHKYkaP9shMmD6NVjOmzYRqHlp5B/ut6LIAZ7U+lhP s7mZwiR1wa2wWO3JM8ziJO4E/DhEbEEKLFDeIP5ufeq6c6/6vRMFgMjllCP3atd1bC2G vHEnE4tOUXFb7DmYfQwfZJUPYX8msRxrpOGImw0BKPg7OJWjAIlOPTGJOaZbUq3A+hPn HIPWTtYKk07BO3De7Uf3x2wcsPRlgKkoN2GH2CpNO+YstSy1IKoJ2rwJR0IbdN8mvvvC B+RQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from; bh=cCASbWwVisKk0+IYaD3kjn19j4r3k7GnMq8Oaal2++I=; b=A7zFaxBHaDP7e76/M8D4EPwVUWKOLF6dledqgW1vtut9iRhhXMNa3pQ1FlNvA3cgt4 FA8SKplqgwCpX+Eg5BCW47naKCLRIpYo3QotVmvgE6u89MbNpG8+zADbtvOyVEmiUJK1 Ci0Isgi4d0kXetEiRrgeNc+/Wyq7PUCmu7zEKTW7dL0220RzaWDIRl+FcVi1GWrywLDR qnxgDacUKU+q3146FDm2FrUzjny09XG1dz26hZjV4AXhcXF5cyGEUUf01ZlaHbt6aT3W b66BcIHtgkB1jqyjz4zSiIXtoWMp8RFU9u0Bqhe38hhk3dPOYrAtgcJpKm9FeoojO07J vUlQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id x16si118099pjt.85.2019.05.23.02.06.39; Thu, 23 May 2019 02:06:39 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730245AbfEWJGi (ORCPT + 30 others); Thu, 23 May 2019 05:06:38 -0400 Received: from foss.arm.com ([217.140.101.70]:40756 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729898AbfEWJGh (ORCPT ); Thu, 23 May 2019 05:06:37 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 66D1515AB; Thu, 23 May 2019 02:06:37 -0700 (PDT) Received: from usa.arm.com (e107155-lin.cambridge.arm.com [10.1.196.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B9A643F575; Thu, 23 May 2019 02:06:34 -0700 (PDT) From: Sudeep Holla To: x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Sudeep Holla , Catalin Marinas , Will Deacon , Oleg Nesterov , Richard Weinberger , jdike@addtoit.com, Steve Capper , Haibo Xu , Bin Lu , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov Subject: [PATCH v4 2/4] x86: simplify _TIF_SYSCALL_EMU handling Date: Thu, 23 May 2019 10:06:16 +0100 Message-Id: <20190523090618.13410-3-sudeep.holla@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190523090618.13410-1-sudeep.holla@arm.com> References: <20190523090618.13410-1-sudeep.holla@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The usage of emulated/_TIF_SYSCALL_EMU flags in syscall_trace_enter seems to be bit overcomplicated than required. Let's simplify it. Cc: Andy Lutomirski Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Acked-by: Oleg Nesterov Signed-off-by: Sudeep Holla --- arch/x86/entry/common.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) -- 2.17.1 diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index a986b3c8294c..0a61705d62ec 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -72,23 +72,18 @@ static long syscall_trace_enter(struct pt_regs *regs) struct thread_info *ti = current_thread_info(); unsigned long ret = 0; - bool emulated = false; u32 work; if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) BUG_ON(regs != task_pt_regs(current)); - work = READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY; + work = READ_ONCE(ti->flags); - if (unlikely(work & _TIF_SYSCALL_EMU)) - emulated = true; - - if ((emulated || (work & _TIF_SYSCALL_TRACE)) && - tracehook_report_syscall_entry(regs)) - return -1L; - - if (emulated) - return -1L; + if (work & (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU)) { + ret = tracehook_report_syscall_entry(regs); + if (ret || (work & _TIF_SYSCALL_EMU)) + return -1L; + } #ifdef CONFIG_SECCOMP /*