From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 41gmm96CQqzF1pk for ; Thu, 2 Aug 2018 07:34:33 +1000 (AEST) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w71LYU21106255 for ; Wed, 1 Aug 2018 17:34:30 -0400 Received: from e13.ny.us.ibm.com (e13.ny.us.ibm.com [129.33.205.203]) by mx0b-001b2d01.pphosted.com with ESMTP id 2kkjahwnnt-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 01 Aug 2018 17:34:30 -0400 Received: from localhost by e13.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 1 Aug 2018 17:34:21 -0400 From: Murilo Opsfelder Araujo To: linux-kernel@vger.kernel.org Cc: "Alastair D'Silva" , Andrew Donnellan , Balbir Singh , Benjamin Herrenschmidt , Christophe Leroy , Cyril Bur , "Eric W . Biederman" , Joe Perches , Michael Ellerman , Michael Neuling , Murilo Opsfelder Araujo , Nicholas Piggin , Paul Mackerras , Simon Guo , Sukadev Bhattiprolu , "Tobin C . Harding" , linuxppc-dev@lists.ozlabs.org, Segher Boessenkool Subject: [PATCH v4 5/6] powerpc: Add show_user_instructions() Date: Wed, 1 Aug 2018 18:33:19 -0300 In-Reply-To: <20180801213320.11203-1-muriloo@linux.ibm.com> References: <20180801213320.11203-1-muriloo@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Message-Id: <20180801213320.11203-6-muriloo@linux.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , show_user_instructions() is a slightly modified version of show_instructions() that allows userspace instruction dump. This will be useful within show_signal_msg() to dump userspace instructions of the faulty location. Here is a sample of what show_user_instructions() outputs: pandafault[10850]: code: 4bfffeec 4bfffee8 3c401002 38427f00 fbe1fff8 f821ffc1 7c3f0b78 3d22fffe pandafault[10850]: code: 392988d0 f93f0020 e93f0020 39400048 <99490000> 39200000 7d234b78 383f0040 The current->comm and current->pid printed can serve as a glue that links the instructions dump to its originator, allowing messages to be interleaved in the logs. Signed-off-by: Murilo Opsfelder Araujo --- arch/powerpc/include/asm/stacktrace.h | 13 +++++++++ arch/powerpc/kernel/process.c | 40 +++++++++++++++++++++++++++ 2 files changed, 53 insertions(+) create mode 100644 arch/powerpc/include/asm/stacktrace.h diff --git a/arch/powerpc/include/asm/stacktrace.h b/arch/powerpc/include/asm/stacktrace.h new file mode 100644 index 000000000000..6149b53b3bc8 --- /dev/null +++ b/arch/powerpc/include/asm/stacktrace.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Stack trace functions. + * + * Copyright 2018, Murilo Opsfelder Araujo, IBM Corporation. + */ + +#ifndef _ASM_POWERPC_STACKTRACE_H +#define _ASM_POWERPC_STACKTRACE_H + +void show_user_instructions(struct pt_regs *regs); + +#endif /* _ASM_POWERPC_STACKTRACE_H */ diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index e9533b4d2f08..364645ac732c 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1299,6 +1299,46 @@ static void show_instructions(struct pt_regs *regs) pr_cont("\n"); } +void show_user_instructions(struct pt_regs *regs) +{ + int i; + const char *prefix = KERN_INFO "%s[%d]: code: "; + unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 * + sizeof(int)); + + printk(prefix, current->comm, current->pid); + + for (i = 0; i < instructions_to_print; i++) { + int instr; + + if (!(i % 8) && (i > 0)) { + pr_cont("\n"); + printk(prefix, current->comm, current->pid); + } + +#if !defined(CONFIG_BOOKE) + /* If executing with the IMMU off, adjust pc rather + * than print XXXXXXXX. + */ + if (!(regs->msr & MSR_IR)) + pc = (unsigned long)phys_to_virt(pc); +#endif + + if (probe_kernel_address((unsigned int __user *)pc, instr)) { + pr_cont("XXXXXXXX "); + } else { + if (regs->nip == pc) + pr_cont("<%08x> ", instr); + else + pr_cont("%08x ", instr); + } + + pc += sizeof(int); + } + + pr_cont("\n"); +} + struct regbit { unsigned long bit; const char *name; -- 2.17.1