From nobody Thu Apr 9 07:50:23 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 349E5C4332F for ; Thu, 3 Nov 2022 07:52:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231527AbiKCHwr (ORCPT ); Thu, 3 Nov 2022 03:52:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231428AbiKCHwW (ORCPT ); Thu, 3 Nov 2022 03:52:22 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EEEFA63F9; Thu, 3 Nov 2022 00:52:06 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 8C13CB82695; Thu, 3 Nov 2022 07:52:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 097C6C43142; Thu, 3 Nov 2022 07:51:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667461924; bh=KyXvA35NcgjlVfSJ4KXXTHO0QhWLea8Z2lvKUOL8H8c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jL2v+zHijdjvlre5lrvJ5TkUiBBKkQun0IFj0/KMhw2sKMz9cPxqh5GF9/DVAkMgg lx2RCFOEY5VlYGGPTGEuNR2aPKmIAIVIsS4mRGSnA7P7oeq+8gqyVb6uqcapSXoWFL 0Xhmba1CnG+ywiP4wMD3uqumUIfxXfdcWvZqLEVBHW+D6+3Tp1nuYRKdP46FAslvGR vCgqO9R2XBCNX4ai5Nx8yznxAWZ79YF2MluK4TySFYuiNtw3XnKUqlSdQuVtt3vpWZ vwWpFSPr/j6UPlUT+25ITOj6nMGvK8OreIOROL8MzDHvg8c7E781FWcbABfMIzkYkF KrZpJGnlO3Ddg== From: guoren@kernel.org To: arnd@arndb.de, guoren@kernel.org, palmer@rivosinc.com, tglx@linutronix.de, peterz@infradead.org, luto@kernel.org, conor.dooley@microchip.com, heiko@sntech.de, jszhang@kernel.org, lazyparser@gmail.com, falcon@tinylab.org, chenhuacai@kernel.org, apatel@ventanamicro.com, atishp@atishpatra.org, palmer@dabbelt.com, paul.walmsley@sifive.com, mark.rutland@arm.com, zouyipeng@huawei.com, bigeasy@linutronix.de, David.Laight@aculab.com, chenzhongjin@huawei.com, greentime.hu@sifive.com, andy.chiu@sifive.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Guo Ren Subject: [PATCH -next V8 05/14] riscv: traps: Add noinstr to prevent instrumentation inserted Date: Thu, 3 Nov 2022 03:50:38 -0400 Message-Id: <20221103075047.1634923-6-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20221103075047.1634923-1-guoren@kernel.org> References: <20221103075047.1634923-1-guoren@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Guo Ren Without noinstr the compiler is free to insert instrumentation (think all the k*SAN, KCov, GCov, ftrace etc..) which can call code we're not yet ready to run this early in the entry path, for instance it could rely on RCU which isn't on yet, or expect lockdep state. (by peterz) Link: https://lore.kernel.org/linux-riscv/YxcQ6NoPf3AH0EXe@hirez.programmin= g.kicks-ass.net/raw Suggested-by: Peter Zijlstra Signed-off-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/kernel/traps.c | 4 ++-- arch/riscv/mm/fault.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index f3e96d60a2ff..f7fa973558bc 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -95,9 +95,9 @@ static void do_trap_error(struct pt_regs *regs, int signo= , int code, } =20 #if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_RISCV_ALTERNATIVE) -#define __trap_section __section(".xip.traps") +#define __trap_section __noinstr_section(".xip.traps") #else -#define __trap_section +#define __trap_section noinstr #endif #define DO_ERROR_INFO(name, signo, code, str) \ asmlinkage __visible __trap_section void name(struct pt_regs *regs) \ diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c index d86f7cebd4a7..b26f68eac61c 100644 --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -204,7 +204,7 @@ static inline bool access_error(unsigned long cause, st= ruct vm_area_struct *vma) * This routine handles page faults. It determines the address and the * problem, and then passes it off to one of the appropriate routines. */ -asmlinkage void do_page_fault(struct pt_regs *regs) +asmlinkage void noinstr do_page_fault(struct pt_regs *regs) { struct task_struct *tsk; struct vm_area_struct *vma; --=20 2.36.1