From patchwork Mon Sep 30 16:10:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kristina Martsenko X-Patchwork-Id: 13816676 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C8CF3CE8360 for ; Mon, 30 Sep 2024 16:16:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Y8zy5eiWPAyXwFAueaF8qRDVKNQSgUHh9cDD/7d4kMg=; b=IHyd6R9MgHISFgM4adh7NxY5sN tyAr+J0UeWYrw8QQyeJKwcOV2FN2P17UHPywfNMmWo/jiHulalrmJGgDaCmDLXXu9gCr7DQczswzH /CF2pkUQtWyB9dT9G9tm372jCAjbj3a6kKnbqZHVAYyC4EM3QEE13IzkUxuQPe1iSIqqgxni8N9vj yOepF6eknM1YVDDDlP61GJjJinzlNA4q9maJg8aexH8Ra+srk3zpqJEYPVRs6RLNh1cYbR5jsbYD2 hbmlQGxGcgjjfp9in31L0EHyMYVUXdylQMoxtCjvcrmKK26JN5dx6r1g4PU4UoENOwxUJRjR8cS/s bSF5h1Dw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1svJ4p-00000000CnY-08Eb; Mon, 30 Sep 2024 16:16:47 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1svJ1G-00000000Bqh-4AaA for linux-arm-kernel@lists.infradead.org; Mon, 30 Sep 2024 16:13:08 +0000 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 1935C367; Mon, 30 Sep 2024 09:13:35 -0700 (PDT) Received: from e126864.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EE33A3F58B; Mon, 30 Sep 2024 09:13:03 -0700 (PDT) From: Kristina Martsenko To: linux-arm-kernel@lists.infradead.org Cc: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Marc Zyngier Subject: [PATCH 2/5] arm64: mops: Handle MOPS exceptions from EL1 Date: Mon, 30 Sep 2024 17:10:48 +0100 Message-Id: <20240930161051.3777828-3-kristina.martsenko@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240930161051.3777828-1-kristina.martsenko@arm.com> References: <20240930161051.3777828-1-kristina.martsenko@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240930_091307_306321_45B31E73 X-CRM114-Status: GOOD ( 12.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org We will soon be using MOPS instructions in the kernel, so wire up the exception handler to handle exceptions from EL1 caused by the copy/set operation being stopped and resumed on a different type of CPU. Add a helper for advancing the single step state machine, similarly to what the EL0 exception handler does. Signed-off-by: Kristina Martsenko --- Note, I haven't looked at whether this needs any kprobes annotations (NOKPROBE_SYMBOL or __kprobes) like some other exception handlers, as my understanding is that it's not currently consistently applied anyway. arch/arm64/include/asm/debug-monitors.h | 1 + arch/arm64/include/asm/exception.h | 1 + arch/arm64/kernel/debug-monitors.c | 5 +++++ arch/arm64/kernel/entry-common.c | 12 ++++++++++++ arch/arm64/kernel/traps.c | 7 +++++++ 5 files changed, 26 insertions(+) diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h index 13d437bcbf58..8f6ba31b8658 100644 --- a/arch/arm64/include/asm/debug-monitors.h +++ b/arch/arm64/include/asm/debug-monitors.h @@ -105,6 +105,7 @@ void kernel_enable_single_step(struct pt_regs *regs); void kernel_disable_single_step(void); int kernel_active_single_step(void); void kernel_rewind_single_step(struct pt_regs *regs); +void kernel_fastforward_single_step(struct pt_regs *regs); #ifdef CONFIG_HAVE_HW_BREAKPOINT int reinstall_suspended_bps(struct pt_regs *regs); diff --git a/arch/arm64/include/asm/exception.h b/arch/arm64/include/asm/exception.h index f296662590c7..8689b95f6b53 100644 --- a/arch/arm64/include/asm/exception.h +++ b/arch/arm64/include/asm/exception.h @@ -73,6 +73,7 @@ void do_el0_svc_compat(struct pt_regs *regs); void do_el0_fpac(struct pt_regs *regs, unsigned long esr); void do_el1_fpac(struct pt_regs *regs, unsigned long esr); void do_el0_mops(struct pt_regs *regs, unsigned long esr); +void do_el1_mops(struct pt_regs *regs, unsigned long esr); void do_serror(struct pt_regs *regs, unsigned long esr); void do_signal(struct pt_regs *regs); diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index 024a7b245056..c60a4a90c6a5 100644 --- a/arch/arm64/kernel/debug-monitors.c +++ b/arch/arm64/kernel/debug-monitors.c @@ -441,6 +441,11 @@ void kernel_rewind_single_step(struct pt_regs *regs) set_regs_spsr_ss(regs); } +void kernel_fastforward_single_step(struct pt_regs *regs) +{ + clear_regs_spsr_ss(regs); +} + /* ptrace API */ void user_enable_single_step(struct task_struct *task) { diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c index 3fcd9d080bf2..9d174cd541ef 100644 --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -463,6 +463,15 @@ static void noinstr el1_bti(struct pt_regs *regs, unsigned long esr) exit_to_kernel_mode(regs); } +static void noinstr el1_mops(struct pt_regs *regs, unsigned long esr) +{ + enter_from_kernel_mode(regs); + local_daif_inherit(regs); + do_el1_mops(regs, esr); + local_daif_mask(); + exit_to_kernel_mode(regs); +} + static void noinstr el1_dbg(struct pt_regs *regs, unsigned long esr) { unsigned long far = read_sysreg(far_el1); @@ -505,6 +514,9 @@ asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs) case ESR_ELx_EC_BTI: el1_bti(regs, esr); break; + case ESR_ELx_EC_MOPS: + el1_mops(regs, esr); + break; case ESR_ELx_EC_BREAKPT_CUR: case ESR_ELx_EC_SOFTSTP_CUR: case ESR_ELx_EC_WATCHPT_CUR: diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 563cbce11126..fc6d44e06b8d 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -531,6 +531,13 @@ void do_el0_mops(struct pt_regs *regs, unsigned long esr) user_fastforward_single_step(current); } +void do_el1_mops(struct pt_regs *regs, unsigned long esr) +{ + arm64_mops_reset_regs(®s->user_regs, esr); + + kernel_fastforward_single_step(regs); +} + #define __user_cache_maint(insn, address, res) \ if (address >= TASK_SIZE_MAX) { \ res = -EFAULT; \