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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 607C0C07E95 for ; Wed, 7 Jul 2021 04:27:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 41FA961CB6 for ; Wed, 7 Jul 2021 04:27:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229477AbhGGEaK (ORCPT ); Wed, 7 Jul 2021 00:30:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47292 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229460AbhGGEaK (ORCPT ); Wed, 7 Jul 2021 00:30:10 -0400 Received: from mail-il1-x129.google.com (mail-il1-x129.google.com [IPv6:2607:f8b0:4864:20::129]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7FAD1C061574 for ; Tue, 6 Jul 2021 21:27:30 -0700 (PDT) Received: by mail-il1-x129.google.com with SMTP id o10so1044806ils.6 for ; Tue, 06 Jul 2021 21:27:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=p7tTvfqKC5/i6mduLXUeFczFs23kjYTbx304GxmNqQk=; b=lJTISIPHDi0wmzj5oeL13MPCQIMdPKzvuxVPzn98QrlgG6oqsKEphK3ErkZX64Qn64 A75x5IMzagT8qcJjBMsO9y9Yhl+rA+x5NQlcwwNTfbudoE7I+2tF2MVMJtvAZCzlYE+u xzeQwE/Llu3SCkTJODkRxSoBDDEf48vL4xiQvQAFY1NAcDVj4jH7l4oxd2C5XYgyR4so m0xAjHHRcEkpYVj89nzPphLVzq0cK1YforBgOGXvS4kVqerpwYTMg9g0FWqfrb231OeB ccawitw9CX5WpWB/EhMz5UDniMzwuo22omSekwzJQukwl1dlKH78CGFn4uCacbM7nent Catg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=p7tTvfqKC5/i6mduLXUeFczFs23kjYTbx304GxmNqQk=; b=TYkanllY3Kpa1IOpha5dynmeKmj3bwxZGALUbZOAXNSFZBrkzuZaV89uvn73eWQrRZ IuaHjUtVVvlWgd5PQpAPUzzJM+jd+U2R7GhwmBsYbqvb61no32grHBLziGQgAJDmkE4/ jgZNczQiEYuUZhzlfASx75X0XFyOOA+23CVeqwTmQtpxbrJTmrAL6fUSKciPUb7evVrB pqn/CTJ79PBqJVkfXoYN4K8C2RF5igBYk59e7RwA3X9siK4GGJf5dg8PQYgiSTVaAEDO 8xEmHqsiQaJzjP0zYoIe6d1JThhOsUCMm+OrzM0fKwHCn2IhWIexRgtpKUBkl8RhXeuV MklQ== X-Gm-Message-State: AOAM531opHLJuMDddrRQxpHzKKTiuEl09tbvcivhOurPCPqm+Qq2LKd1 +qna7HVEV07u4aE25E1uwzzqcJpM8VrV9f/CLU4= X-Google-Smtp-Source: ABdhPJys56E6JLu7pT51obI7IACMXo6n8hTOjOw/Ko6WHk3uxl3d2qhUzaQ8cOlY6bh+uMjDYvQ+04k7jQH663AixpE= X-Received: by 2002:a92:6509:: with SMTP id z9mr17074621ilb.184.1625632048603; Tue, 06 Jul 2021 21:27:28 -0700 (PDT) MIME-Version: 1.0 References: <20210706041820.1536502-1-chenhuacai@loongson.cn> <20210706041820.1536502-10-chenhuacai@loongson.cn> <87tul7r1nq.ffs@nanos.tec.linutronix.de> In-Reply-To: <87tul7r1nq.ffs@nanos.tec.linutronix.de> From: Huacai Chen Date: Wed, 7 Jul 2021 12:27:17 +0800 Message-ID: Subject: Re: [PATCH 09/19] LoongArch: Add system call support To: Thomas Gleixner Cc: Huacai Chen , Arnd Bergmann , Andy Lutomirski , Peter Zijlstra , Andrew Morton , David Airlie , Linus Torvalds , linux-arch , Xuefeng Li , Jiaxun Yang Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org Hi, Thomas, On Tue, Jul 6, 2021 at 9:51 PM Thomas Gleixner wrote: > > Chen! > > On Tue, Jul 06 2021 at 12:18, Huacai Chen wrote: > > + li.d t1, _TIF_WORK_SYSCALL_ENTRY > > + LONG_L t0, tp, TI_FLAGS # syscall tracing enabled? > > + and t0, t1, t0 > > + bnez t0, syscall_trace_entry > > + > > +syscall_common: > > + /* Check to make sure we don't jump to a bogus syscall number. */ > > + li.w t0, __NR_syscalls > > + sub.d t2, a7, t0 > > + bgez t2, illegal_syscall > > + > > + /* Syscall number held in a7 */ > > + slli.d t0, a7, 3 # offset into table > > + la t2, sys_call_table > > + add.d t0, t2, t0 > > + ld.d t2, t0, 0 #syscall routine > > + beqz t2, illegal_syscall > > + > > + jalr t2 # Do The Real Thing (TM) > > + > > + ld.d t1, sp, PT_R11 # syscall number > > + addi.d t1, t1, 1 # +1 for handle_signal > > + st.d t1, sp, PT_R0 # save it for syscall restarting > > + st.d v0, sp, PT_R4 # result > > Please do not add _again_ TIF handling in ASM. Please use the generic > entry code infrastructure for this. It handles the complete set of TIF > bits (if enabled in config) out of the box and it does so correctly. OK, thanks, I will improve. Huacai > > Thanks, > > tglx > >