From patchwork Tue Mar 1 21:27:35 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Feiner X-Patchwork-Id: 8470631 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id B45339F9A0 for ; Tue, 1 Mar 2016 21:27:52 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id AE1792034B for ; Tue, 1 Mar 2016 21:27:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 88CA620351 for ; Tue, 1 Mar 2016 21:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751431AbcCAV1r (ORCPT ); Tue, 1 Mar 2016 16:27:47 -0500 Received: from mail-pf0-f175.google.com ([209.85.192.175]:32895 "EHLO mail-pf0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751501AbcCAV1p (ORCPT ); Tue, 1 Mar 2016 16:27:45 -0500 Received: by mail-pf0-f175.google.com with SMTP id 124so58166163pfg.0 for ; Tue, 01 Mar 2016 13:27:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=P2gUkABFvZePJ4bGYkv4o50b4avNZ7EI4swPhl9Jx10=; b=jIzkqmS7LznUSQsT8Ii4lcHAh+Xqx7En781jR+HU6BrivBAuFmMO4P56/kjG2jGhZ3 zi9w3ADVlt/IQRU7mH+Gj6GzWINhQeXjm3m2aMcuZUKnvvTtXePZ/4DG6UMQylHtTGJw yfNUmsprOlQAPhwVEQl1gs6cr9A6ozUvdZK+2505etz2QLAYYc+O7/sVUXYFfn4cIibz fwXFOuLSxZvl5RSxLrjAwWHRb1fd4Kb9ag/8I51NVJr5LKwTzIlggPyumQWSXRO7H0Te Be0HYhKqxdWIQHIMxKb5WG7U318Ba3Y0EXD+1olU60n5/kpj+5W//H9fB5L9lrX2a8zX LXOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=P2gUkABFvZePJ4bGYkv4o50b4avNZ7EI4swPhl9Jx10=; b=lF44LbLBFaO742YL3W+wg2Y0JLBXFfW4HdY7I9vZOxorIsXK98SlfcYlzJE54Pukep unKO8UxpYwR6E4D6PjIUn2c2SP8dOYdTzT9sLcUPG+2poHJcVNwgevbJ05MSIM4tEIUw qgVrNGO4eDHLgc9Gl3n1K6oSHNLCo/k1uST1vX589KVa/Gfxd41SRJYHCOCoz9C0ZqCY aSv59fujR8z1mtd2neFeEHxm81tsCz6eif5adh3OqE07mpmCz4/eMB1kdLGZv7HebbZ5 pVlYyiFcP/J9fWYDP/qJzmPrZUcEEOOqChHBzlf+o1QK1dcKVsnczz7EVXrz3GCfuuXC u90A== X-Gm-Message-State: AD7BkJLaxw9TbfKMDtQuT+Gk/87KLNx78NEwmD6qJk3NQf0ekcvhcYrxUQrq7gE3w6r0PIZV X-Received: by 10.98.93.2 with SMTP id r2mr33435566pfb.64.1456867664770; Tue, 01 Mar 2016 13:27:44 -0800 (PST) Received: from localhost ([2620:0:1009:3:b1e9:1d95:1ce5:e70c]) by smtp.gmail.com with ESMTPSA id r68sm47646045pfb.51.2016.03.01.13.27.43 (version=TLS1_2 cipher=AES128-SHA bits=128/128); Tue, 01 Mar 2016 13:27:44 -0800 (PST) From: Peter Feiner To: kvm@vger.kernel.org, drjones@redhat.com, pbonzini@redhat.com Cc: pfeiner@google.com Subject: [kvm-unit-tests 2/5] lib: backtrace printing Date: Tue, 1 Mar 2016 13:27:35 -0800 Message-Id: <1456867658-10937-3-git-send-email-pfeiner@google.com> X-Mailer: git-send-email 2.7.0.rc3.207.g0ac5344 In-Reply-To: <1456867658-10937-1-git-send-email-pfeiner@google.com> References: <1456867658-10937-1-git-send-email-pfeiner@google.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Functions to walk stack and print backtrace. The stack's unadorned as STACK: addr addr addr ... A follow-up patch post-processes the output to pretty-print the stack. Stack walker is just a stub on arm and ppc. Signed-off-by: Peter Feiner --- Makefile | 2 +- arm/Makefile.common | 1 + lib/arm/dump_stack.c | 6 ++++++ lib/libcflat.h | 4 ++++ lib/powerpc/dump_stack.c | 6 ++++++ lib/printf.c | 37 +++++++++++++++++++++++++++++++++++++ lib/x86/dump_stack.c | 24 ++++++++++++++++++++++++ powerpc/Makefile.common | 1 + x86/Makefile.common | 1 + 9 files changed, 81 insertions(+), 1 deletion(-) create mode 100644 lib/arm/dump_stack.c create mode 100644 lib/powerpc/dump_stack.c create mode 100644 lib/x86/dump_stack.c diff --git a/Makefile b/Makefile index ddba941..0ffa5e7 100644 --- a/Makefile +++ b/Makefile @@ -42,7 +42,7 @@ cc-option = $(shell if $(CC) $(1) -S -o /dev/null -xc /dev/null \ CFLAGS += -g CFLAGS += $(autodepend-flags) -Wall -CFLAGS += $(call cc-option, -fomit-frame-pointer, "") +CFLAGS += $(call cc-option, -fno-omit-frame-pointer, "") CFLAGS += $(call cc-option, -fno-stack-protector, "") CFLAGS += $(call cc-option, -fno-stack-protector-all, "") diff --git a/arm/Makefile.common b/arm/Makefile.common index dd3a0ca..054bdee 100644 --- a/arm/Makefile.common +++ b/arm/Makefile.common @@ -39,6 +39,7 @@ cflatobjs += lib/arm/mmu.o cflatobjs += lib/arm/bitops.o cflatobjs += lib/arm/psci.o cflatobjs += lib/arm/smp.o +cflatobjs += lib/arm/dump_stack.o libeabi = lib/arm/libeabi.a eabiobjs = lib/arm/eabi_compat.o diff --git a/lib/arm/dump_stack.c b/lib/arm/dump_stack.c new file mode 100644 index 0000000..528ba63 --- /dev/null +++ b/lib/arm/dump_stack.c @@ -0,0 +1,6 @@ +#include "libcflat.h" + +int walk_stack(unsigned long bp, unsigned long *stack, int max_depth) +{ + return 0; +} diff --git a/lib/libcflat.h b/lib/libcflat.h index 1f0049c..42c94df 100644 --- a/lib/libcflat.h +++ b/lib/libcflat.h @@ -65,6 +65,10 @@ extern void report_xfail(const char *msg_fmt, bool xfail, bool pass, ...); extern void report_abort(const char *msg_fmt, ...); extern int report_summary(void); +int walk_stack(unsigned long bp, unsigned long *stack, int max_depth); +void dump_stack(unsigned long ip, unsigned long bp); +void dump_current_stack(void); + #define ARRAY_SIZE(_a) (sizeof(_a)/sizeof((_a)[0])) #define container_of(ptr, type, member) ({ \ diff --git a/lib/powerpc/dump_stack.c b/lib/powerpc/dump_stack.c new file mode 100644 index 0000000..528ba63 --- /dev/null +++ b/lib/powerpc/dump_stack.c @@ -0,0 +1,6 @@ +#include "libcflat.h" + +int walk_stack(unsigned long bp, unsigned long *stack, int max_depth) +{ + return 0; +} diff --git a/lib/printf.c b/lib/printf.c index 2aec59a..e97fca9 100644 --- a/lib/printf.c +++ b/lib/printf.c @@ -259,3 +259,40 @@ int printf(const char *fmt, ...) puts(buf); return r; } + +static void print_stack(unsigned long *stack, int depth, + bool top_is_return_address) +{ + int i; + + printf("\tSTACK: " ); + for (i = 0; i < depth; i++) { + int offset = -1; + if (i == 0 && !top_is_return_address) + offset = 0; + printf(" %lx", stack[i] + offset); + } + printf("\n"); +} + +#define MAX_DEPTH 10 + +void dump_stack(unsigned long ip, unsigned long bp) +{ + unsigned long stack[MAX_DEPTH]; + int depth; + + stack[0] = ip; + depth = walk_stack(bp, &stack[1], MAX_DEPTH - 1); + print_stack(stack, depth + 1, false); +} + +void dump_current_stack(void) +{ + unsigned long stack[MAX_DEPTH]; + int depth; + + depth = walk_stack((unsigned long)__builtin_frame_address(1), stack, + MAX_DEPTH); + print_stack(stack, depth, true); +} diff --git a/lib/x86/dump_stack.c b/lib/x86/dump_stack.c new file mode 100644 index 0000000..6e9d126 --- /dev/null +++ b/lib/x86/dump_stack.c @@ -0,0 +1,24 @@ +#include "libcflat.h" + +int walk_stack(unsigned long bp, unsigned long *stack, int max_depth) +{ + static int walking; + int depth = 0; + unsigned long *frame = (unsigned long *) bp; + + if (walking) { + printf("RECURSIVE STACK WALK!!!\n"); + return 0; + } + walking = 1; + + for (depth = 0; depth < max_depth; depth++) { + stack[depth] = frame[1]; + if (stack[depth] == 0) + break; + frame = (unsigned long *) frame[0]; + } + + walking = 0; + return depth; +} diff --git a/powerpc/Makefile.common b/powerpc/Makefile.common index cc27ac8..97f5ddc 100644 --- a/powerpc/Makefile.common +++ b/powerpc/Makefile.common @@ -30,6 +30,7 @@ cflatobjs += lib/powerpc/io.o cflatobjs += lib/powerpc/hcall.o cflatobjs += lib/powerpc/setup.o cflatobjs += lib/powerpc/rtas.o +cflatobjs += lib/powerpc/dump_stack.o FLATLIBS = $(libcflat) $(LIBFDT_archive) %.elf: LDFLAGS = $(arch_LDFLAGS) -nostdlib -pie diff --git a/x86/Makefile.common b/x86/Makefile.common index 3a14fea..250d95d 100644 --- a/x86/Makefile.common +++ b/x86/Makefile.common @@ -12,6 +12,7 @@ cflatobjs += lib/x86/atomic.o cflatobjs += lib/x86/desc.o cflatobjs += lib/x86/isr.o cflatobjs += lib/x86/acpi.o +cflatobjs += lib/x86/dump_stack.o $(libcflat): LDFLAGS += -nostdlib $(libcflat): CFLAGS += -ffreestanding -I lib