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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 93E26C433DB for ; Mon, 25 Jan 2021 15:05:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 546F622D50 for ; Mon, 25 Jan 2021 15:05:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729810AbhAYPFO (ORCPT ); Mon, 25 Jan 2021 10:05:14 -0500 Received: from pegase1.c-s.fr ([93.17.236.30]:11163 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727836AbhAYOvk (ORCPT ); Mon, 25 Jan 2021 09:51:40 -0500 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 4DPXmX4r61z9v0Hr; Mon, 25 Jan 2021 15:48:28 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id 1SMbAHnHO53s; Mon, 25 Jan 2021 15:48:28 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 4DPXmX450Yz9v0Hk; Mon, 25 Jan 2021 15:48:28 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 111F18B79F; Mon, 25 Jan 2021 15:48:34 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id C3W8oAuRvqbX; Mon, 25 Jan 2021 15:48:33 +0100 (CET) Received: from po16121vm.idsi0.si.c-s.fr (po15451.idsi0.si.c-s.fr [172.25.230.103]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 8374B8B79E; Mon, 25 Jan 2021 15:48:33 +0100 (CET) Received: by po16121vm.idsi0.si.c-s.fr (Postfix, from userid 0) id 7749B66AD8; Mon, 25 Jan 2021 14:48:33 +0000 (UTC) Message-Id: In-Reply-To: References: From: Christophe Leroy Subject: [PATCH v4 20/23] powerpc/syscall: Do not check unsupported scv vector on PPC32 To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , npiggin@gmail.com, msuchanek@suse.de Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Date: Mon, 25 Jan 2021 14:48:33 +0000 (UTC) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Only PPC64 has scv. No need to check the 0x7ff0 trap on PPC32. And ignore the scv parameter in syscall_exit_prepare (Save 14 cycles 346 => 332 cycles) Signed-off-by: Christophe Leroy --- arch/powerpc/kernel/entry_32.S | 1 - arch/powerpc/kernel/syscall.c | 7 +++++-- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 9922a04650f7..6ae9c7bcb06c 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -343,7 +343,6 @@ transfer_to_syscall: ret_from_syscall: addi r4,r1,STACK_FRAME_OVERHEAD - li r5,0 bl syscall_exit_prepare #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) /* If the process has its own DBCR0 value, load it up. The internal diff --git a/arch/powerpc/kernel/syscall.c b/arch/powerpc/kernel/syscall.c index 476909b11051..30f8a397a522 100644 --- a/arch/powerpc/kernel/syscall.c +++ b/arch/powerpc/kernel/syscall.c @@ -86,7 +86,7 @@ notrace long system_call_exception(long r3, long r4, long r5, local_irq_enable(); if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) { - if (unlikely(regs->trap == 0x7ff0)) { + if (IS_ENABLED(CONFIG_PPC64) && unlikely(regs->trap == 0x7ff0)) { /* Unsupported scv vector */ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); return regs->gpr[3]; @@ -109,7 +109,7 @@ notrace long system_call_exception(long r3, long r4, long r5, r8 = regs->gpr[8]; } else if (unlikely(r0 >= NR_syscalls)) { - if (unlikely(regs->trap == 0x7ff0)) { + if (IS_ENABLED(CONFIG_PPC64) && unlikely(regs->trap == 0x7ff0)) { /* Unsupported scv vector */ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); return regs->gpr[3]; @@ -187,6 +187,9 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3, unsigned long ti_flags; unsigned long ret = 0; + if (IS_ENABLED(CONFIG_PPC32)) + scv = 0; + CT_WARN_ON(ct_state() == CONTEXT_USER); kuap_check(); -- 2.25.0