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,URIBL_BLOCKED, 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 29BCDC43381 for ; Thu, 28 Feb 2019 18:36:52 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B13BB218AE for ; Thu, 28 Feb 2019 18:36:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B13BB218AE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 449Lqh6cqRzDqM9 for ; Fri, 1 Mar 2019 05:36:48 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=arm.com (client-ip=217.140.101.70; helo=foss.arm.com; envelope-from=sudeep.holla@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by lists.ozlabs.org (Postfix) with ESMTP id 449Lkw0sw0zDqJl for ; Fri, 1 Mar 2019 05:32:39 +1100 (AEDT) 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 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> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Haibo Xu , Steve Capper , jdike@addtoit.com, Sudeep Holla , Will Deacon , Oleg Nesterov , Bin Lu , Richard Weinberger , Ingo Molnar , Paul Mackerras , Andy Lutomirski , Catalin Marinas , Borislav Petkov , Thomas Gleixner Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" 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