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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 E9D33C43381 for ; Thu, 28 Feb 2019 18:32:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA30F218AE for ; Thu, 28 Feb 2019 18:32:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387658AbfB1Sck (ORCPT ); Thu, 28 Feb 2019 13:32:40 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52918 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732645AbfB1Sci (ORCPT ); Thu, 28 Feb 2019 13:32:38 -0500 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 2508416A3; Thu, 28 Feb 2019 10:32:38 -0800 (PST) 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 0DDEE3F5C1; Thu, 28 Feb 2019 10:32:34 -0800 (PST) From: Sudeep Holla To: x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Cc: Sudeep Holla , Catalin Marinas , Will Deacon , Oleg Nesterov , Paul Mackerras , Michael Ellerman , Thomas Gleixner , Ingo Molnar , Richard Weinberger , jdike@addtoit.com, Steve Capper , Haibo Xu , Bin Lu , Andy Lutomirski , Borislav Petkov Subject: [PATCH 3/6] x86: clean up _TIF_SYSCALL_EMU handling using ptrace_syscall_enter hook Date: Thu, 28 Feb 2019 18:32:17 +0000 Message-Id: <20190228183220.15626-4-sudeep.holla@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190228183220.15626-1-sudeep.holla@arm.com> References: <20190228183220.15626-1-sudeep.holla@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that we have a new hook ptrace_syscall_enter that can be called from syscall entry code and it handles PTRACE_SYSEMU in generic code, we can do some cleanup using the same in syscall_trace_enter. Further the extra logic to find single stepping PTRACE_SYSEMU_SINGLESTEP in syscall_slow_exit_work seems unnecessary. Let's remove the same. Cc: Andy Lutomirski Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Signed-off-by: Sudeep Holla --- arch/x86/entry/common.c | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-) diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 7bc105f47d21..36457c1f87d2 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -70,22 +70,16 @@ 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; - - if (unlikely(work & _TIF_SYSCALL_EMU)) - emulated = true; - - if ((emulated || (work & _TIF_SYSCALL_TRACE)) && - tracehook_report_syscall_entry(regs)) + if (unlikely(ptrace_syscall_enter(regs))) return -1L; - if (emulated) + work = READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY; + if ((work & _TIF_SYSCALL_TRACE) && tracehook_report_syscall_entry(regs)) return -1L; #ifdef CONFIG_SECCOMP @@ -227,15 +221,7 @@ static void syscall_slow_exit_work(struct pt_regs *regs, u32 cached_flags) if (cached_flags & _TIF_SYSCALL_TRACEPOINT) trace_sys_exit(regs, regs->ax); - /* - * If TIF_SYSCALL_EMU is set, we only get here because of - * TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP). - * We already reported this syscall instruction in - * syscall_trace_enter(). - */ - step = unlikely( - (cached_flags & (_TIF_SINGLESTEP | _TIF_SYSCALL_EMU)) - == _TIF_SINGLESTEP); + step = unlikely((cached_flags & _TIF_SINGLESTEP)); if (step || cached_flags & _TIF_SYSCALL_TRACE) tracehook_report_syscall_exit(regs, step); } -- 2.17.1