From patchwork Wed Jan 22 21:21:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 11346403 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 38CA592A for ; Wed, 22 Jan 2020 21:22:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1772624689 for ; Wed, 22 Jan 2020 21:22:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579728138; bh=FQBBXk4FIMALOPvBJKJqqvFENt1GTTnVYlkDeebCbwg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=K4rBd7ADc0M5vhhD3Cdt1XNfWp8Yp5t8eGEQ/OVvXfx+P4utUac5x4QMyzB01MzMC Hs2XV8beSMmUAyPoMobyVYCjFuwQCYMGtLslX54ZykxOytntCCX26U5iB/ki9i47at bxixxzTwl9vA3Gs2kQSPxSdJWArpqZ9ByMFVY2Kk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729334AbgAVVWR (ORCPT ); Wed, 22 Jan 2020 16:22:17 -0500 Received: from foss.arm.com ([217.140.110.172]:60976 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729299AbgAVVWP (ORCPT ); Wed, 22 Jan 2020 16:22:15 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 38BE213A1; Wed, 22 Jan 2020 13:22:15 -0800 (PST) Received: from localhost (unknown [10.37.6.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9A2D63F52E; Wed, 22 Jan 2020 13:22:12 -0800 (PST) From: Mark Brown To: Catalin Marinas , Will Deacon Cc: Alexander Viro , Paul Elliott , Peter Zijlstra , Yu-cheng Yu , Amit Kachhap , Vincenzo Frascino , Marc Zyngier , Eugene Syromiatnikov , Szabolcs Nagy , "H . J . Lu " , Andrew Jones , Kees Cook , Arnd Bergmann , Jann Horn , Richard Henderson , =?utf-8?q?Kristina_Mart?= =?utf-8?q?=C5=A1enko?= , Thomas Gleixner , Florian Weimer , Sudakshina Das , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, Dave Martin , Mark Rutland , Mark Brown Subject: [PATCH v5 08/12] arm64: unify native/compat instruction skipping Date: Wed, 22 Jan 2020 21:21:40 +0000 Message-Id: <20200122212144.6409-9-broonie@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200122212144.6409-1-broonie@kernel.org> References: <20200122212144.6409-1-broonie@kernel.org> MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Dave Martin Skipping of an instruction on AArch32 works a bit differently from AArch64, mainly due to the different CPSR/PSTATE semantics. Currently arm64_skip_faulting_instruction() is only suitable for AArch64, and arm64_compat_skip_faulting_instruction() handles the IT state machine but is local to traps.c. Since manual instruction skipping implies a trap, it's a relatively slow path. So, make arm64_skip_faulting_instruction() handle both compat and native, and get rid of the arm64_compat_skip_faulting_instruction() special case. Signed-off-by: Dave Martin Reviewed-by: Mark Rutland Signed-off-by: Mark Brown --- arch/arm64/kernel/traps.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 84c7a88dd617..d42f0693623a 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -269,6 +269,8 @@ void arm64_notify_die(const char *str, struct pt_regs *regs, } } +static void advance_itstate(struct pt_regs *regs); + void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size) { regs->pc += size; @@ -279,6 +281,9 @@ void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size) */ if (user_mode(regs)) user_fastforward_single_step(current); + + if (compat_user_mode(regs)) + advance_itstate(regs); } static LIST_HEAD(undef_hook); @@ -641,19 +646,12 @@ static void advance_itstate(struct pt_regs *regs) compat_set_it_state(regs, it); } -static void arm64_compat_skip_faulting_instruction(struct pt_regs *regs, - unsigned int sz) -{ - advance_itstate(regs); - arm64_skip_faulting_instruction(regs, sz); -} - static void compat_cntfrq_read_handler(unsigned int esr, struct pt_regs *regs) { int reg = (esr & ESR_ELx_CP15_32_ISS_RT_MASK) >> ESR_ELx_CP15_32_ISS_RT_SHIFT; pt_regs_write_reg(regs, reg, arch_timer_get_rate()); - arm64_compat_skip_faulting_instruction(regs, 4); + arm64_skip_faulting_instruction(regs, 4); } static const struct sys64_hook cp15_32_hooks[] = { @@ -673,7 +671,7 @@ static void compat_cntvct_read_handler(unsigned int esr, struct pt_regs *regs) pt_regs_write_reg(regs, rt, lower_32_bits(val)); pt_regs_write_reg(regs, rt2, upper_32_bits(val)); - arm64_compat_skip_faulting_instruction(regs, 4); + arm64_skip_faulting_instruction(regs, 4); } static const struct sys64_hook cp15_64_hooks[] = { @@ -694,7 +692,7 @@ void do_cp15instr(unsigned int esr, struct pt_regs *regs) * There is no T16 variant of a CP access, so we * always advance PC by 4 bytes. */ - arm64_compat_skip_faulting_instruction(regs, 4); + arm64_skip_faulting_instruction(regs, 4); return; }