Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753166AbbDXB6P (ORCPT ); Thu, 23 Apr 2015 21:58:15 -0400 Received: from mo2.mail-out.ovh.net ([178.32.228.2]:45107 "EHLO mo2.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753131AbbDXB6O (ORCPT ); Thu, 23 Apr 2015 21:58:14 -0400 X-Greylist: delayed 152697 seconds by postgrey-1.27 at vger.kernel.org; Thu, 23 Apr 2015 21:58:13 EDT Message-ID: <5539A30A.8010600@weksteen.fr> Date: Fri, 24 Apr 2015 11:57:30 +1000 From: =?UTF-8?B?VGhpw6liYXVkIFdla3N0ZWVu?= User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: linux-kernel@vger.kernel.org CC: Jan Kiszka Subject: [PATCH v2] scripts/gdb: Add command to check list consistency Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Ovh-Tracer-Id: 11946360962845856278 X-Ovh-Remote: 121.44.82.37 (ppp121-44-82-37.lns20.syd4.internode.on.net) X-Ovh-Local: 213.186.33.20 (ns0.ovh.net) X-OVH-SPAMSTATE: OK X-OVH-SPAMSCORE: -100 X-OVH-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeektddrieduucetufdoteggodetrfcurfhrohhfihhlvgemucfqggfjnecuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeektddrieduucetufdoteggodetrfcurfhrohhfihhlvgemucfqggfjnecuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4872 Lines: 148 Add a gdb script to verify the consistency of lists. Signed-off-by: Thiébaud Weksteen --- Implement suggestions from Jan. Changes in v2: - Add copyright line - Rename check_list to list_check - Remove casting and only accept (struct list_head) object - Add error message if argument is missing - Reformat error messages to include address of nodes Example of use: (gdb) lx-list-check workqueues Starting with: {next = 0xf3aea5a8, prev = 0xf580e668} list is consistent: 30 node(s) (gdb) set *((int *) 0xf3934908) = 0x0 (gdb) lx-list-check workqueues Starting with: {next = 0xf3aea5a8, prev = 0xf580e668} next is not accessible: current@0xf3934908={next = 0x0, prev = 0xf3aea5a8} (gdb) set *((int *) 0xf3934908) = 0xdeadbeef (gdb) lx-list-check workqueues Starting with: {next = 0xf3aea5a8, prev = 0xf580e668} next.prev != current: current@0xf3934908={next = 0xdeadbeef, prev = 0xf3aea5a8} next@0xdeadbeef={next = 0x0, prev = 0x0} (gdb) set *((int *) 0xf3934908) = 0xf537f188 (gdb) lx-list-check workqueues Starting with: {next = 0xf3aea5a8, prev = 0xf580e668} list is consistent: 30 node(s) scripts/gdb/linux/lists.py | 89 ++++++++++++++++++++++++++++++++++++++++++++++ scripts/gdb/vmlinux-gdb.py | 1 + 2 files changed, 90 insertions(+) create mode 100644 scripts/gdb/linux/lists.py diff --git a/scripts/gdb/linux/lists.py b/scripts/gdb/linux/lists.py new file mode 100644 index 0000000..2a94b54 --- /dev/null +++ b/scripts/gdb/linux/lists.py @@ -0,0 +1,89 @@ +# +# gdb helper commands and functions for Linux kernel debugging +# +# list tools +# +# Copyright (c) Thiebaud Weksteen, 2015 +# +# Authors: +# Thiebaud Weksteen +# +# This work is licensed under the terms of the GNU GPL version 2. +# + +import gdb + +from linux import utils + +list_head = utils.CachedType("struct list_head") + + +def list_check(head): + nb = 0 + c = head + if (c.type != list_head.get_type()): + raise gdb.GdbError('The argument should be of type (struct list_head)') + try: + gdb.write("Starting with: {}\n".format(c)) + except gdb.MemoryError: + gdb.write('head is not accessible\n') + return + while True: + p = c['prev'].dereference() + n = c['next'].dereference() + try: + if p['next'] != c.address: + gdb.write('prev.next != current: ' + 'current@{current_addr}={current} ' + 'prev@{p_addr}={p}\n'.format( + current_addr=c.address, + current=c, + p_addr=p.address, + p=p, + )) + return + except gdb.MemoryError: + gdb.write('prev is not accessible: ' + 'current@{current_addr}={current}\n'.format( + current_addr=c.address, + current=c + )) + return + try: + if n['prev'] != c.address: + gdb.write('next.prev != current: ' + 'current@{current_addr}={current} ' + 'next@{n_addr}={n}\n'.format( + current_addr=c.address, + current=c, + n_addr=n.address, + n=n, + )) + return + except gdb.MemoryError: + gdb.write('next is not accessible: ' + 'current@{current_addr}={current}\n'.format( + current_addr=c.address, + current=c + )) + return + c = n + nb += 1 + if c == head: + gdb.write("list is consistent: {} node(s)\n".format(nb)) + return + + +class LxListChk(gdb.Command): + """Verify a list consistency""" + + def __init__(self): + super(LxListChk, self).__init__("lx-list-check", gdb.COMMAND_DATA) + + def invoke(self, arg, from_tty): + argv = gdb.string_to_argv(arg) + if len(argv) != 1: + raise gdb.GdbError("lx-list-check takes one argument") + list_check(gdb.parse_and_eval(argv[0])) + +LxListChk() diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py index 4848928..ce82bf5 100644 --- a/scripts/gdb/vmlinux-gdb.py +++ b/scripts/gdb/vmlinux-gdb.py @@ -28,3 +28,4 @@ else: import linux.dmesg import linux.tasks import linux.cpus + import linux.lists -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/