From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933289AbcI0HtE (ORCPT ); Tue, 27 Sep 2016 03:49:04 -0400 Received: from mail-yw0-f175.google.com ([209.85.161.175]:34496 "EHLO mail-yw0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932881AbcI0HsU (ORCPT ); Tue, 27 Sep 2016 03:48:20 -0400 From: Pratyush Anand To: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com Cc: linux@arm.linux.org.uk, will.deacon@arm.com, linux-kernel@vger.kernel.org, wcohen@redhat.com, oleg@redhat.com, dave.long@linaro.org, steve.capper@linaro.org, srikar@linux.vnet.ibm.com, vijaya.kumar@caviumnetworks.com, panand@redhat.com Subject: [PATCH V2 3/6] arm64: Handle TRAP_TRACE for user mode as well Date: Tue, 27 Sep 2016 13:17:57 +0530 Message-Id: X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org uprobe registers a handler at step_hook. So, single_step_handler now checks for user mode as well if there is a valid hook. Signed-off-by: Pratyush Anand --- arch/arm64/kernel/debug-monitors.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index 73ae90ef434c..a8f8de012250 100644 --- a/arch/arm64/kernel/debug-monitors.c +++ b/arch/arm64/kernel/debug-monitors.c @@ -226,6 +226,8 @@ static void send_user_sigtrap(int si_code) static int single_step_handler(unsigned long addr, unsigned int esr, struct pt_regs *regs) { + bool handler_found = false; + /* * If we are stepping a pending breakpoint, call the hw_breakpoint * handler first. @@ -233,7 +235,14 @@ static int single_step_handler(unsigned long addr, unsigned int esr, if (!reinstall_suspended_bps(regs)) return 0; - if (user_mode(regs)) { +#ifdef CONFIG_KPROBES + if (kprobe_single_step_handler(regs, esr) == DBG_HOOK_HANDLED) + handler_found = true; +#endif + if (!handler_found && call_step_hook(regs, esr) == DBG_HOOK_HANDLED) + handler_found = true; + + if (!handler_found && user_mode(regs)) { send_user_sigtrap(TRAP_TRACE); /* @@ -243,15 +252,8 @@ static int single_step_handler(unsigned long addr, unsigned int esr, * to the active-not-pending state). */ user_rewind_single_step(current); - } else { -#ifdef CONFIG_KPROBES - if (kprobe_single_step_handler(regs, esr) == DBG_HOOK_HANDLED) - return 0; -#endif - if (call_step_hook(regs, esr) == DBG_HOOK_HANDLED) - return 0; - - pr_warning("Unexpected kernel single-step exception at EL1\n"); + } else if (!handler_found) { + pr_warn("Unexpected kernel single-step exception at EL1\n"); /* * Re-enable stepping since we know that we will be * returning to regs. -- 2.7.4