From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, T_DKIMWL_WL_HIGH,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27B82C04AB5 for ; Mon, 3 Jun 2019 12:41:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F1CFC27E12 for ; Mon, 3 Jun 2019 12:41:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559565674; bh=purKlpevxX3/NR3bDCz6o1xMW5szM0zAXaiUthXoA0U=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=bmekLzIvMaXS5pFslW+scyGb8WKlW4Lz1ZOKWTIJK9HrxP14YOKkVfRXBNfpuWHqK 1F0kRP5VfjmJ2oOMSmKy3ZlfBGOu4ehgD7tHe6IE82w3JHg6WBD/F9wu/Xc617pjV6 GXZYtMa2zRwYJPV4TmX10WQxNH70qbX8H3cpHC5Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727387AbfFCMlM (ORCPT ); Mon, 3 Jun 2019 08:41:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:54392 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726137AbfFCMlM (ORCPT ); Mon, 3 Jun 2019 08:41:12 -0400 Received: from devnote2 (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2A2D425FCC; Mon, 3 Jun 2019 12:41:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559565670; bh=purKlpevxX3/NR3bDCz6o1xMW5szM0zAXaiUthXoA0U=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=oIZuSZQ3HNjdYL9Uax26ZKlLqdFY7cxDE9izwPcPzn2ztTWZIitCGV2cG+R/V6pjJ ZCEL/kr8yiiclHuZpXrYEwPjl0XjWFuPx8kCMZ3qTYzUwqX3ZBHVaJKuJnxVP0fhxN ieA70HfpZDhxDPP8uKjnGBl1lWvqfWrkQYucpfl8= Date: Mon, 3 Jun 2019 21:41:05 +0900 From: Masami Hiramatsu To: Masami Hiramatsu Cc: Anders Roxell , Steven Rostedt , Ingo Molnar , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , Linux Kernel Mailing List , linux-doc@vger.kernel.org Subject: Re: [PATCH v2 2/2] tracing/kprobe: Add kprobe_event= boot parameter Message-Id: <20190603214105.715a4072472ef4946123dc20@kernel.org> In-Reply-To: <20190603205238.3cef1ef724bda35d11369ea7@kernel.org> References: <155851393823.15728.9489409117921369593.stgit@devnote2> <155851395498.15728.830529496248543583.stgit@devnote2> <20190528083629.3c100256@gandalf.local.home> <20190603205238.3cef1ef724bda35d11369ea7@kernel.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 3 Jun 2019 20:52:38 +0900 Masami Hiramatsu wrote: > Hi Anders, > > Sorry for replying later. > > On Tue, 28 May 2019 15:39:15 +0200 > Anders Roxell wrote: > > > On Tue, 28 May 2019 at 14:36, Steven Rostedt wrote: > > > > > > On Tue, 28 May 2019 14:23:43 +0200 > > > Anders Roxell wrote: > > > > > > > On Wed, 22 May 2019 at 10:32, Masami Hiramatsu wrote: > > > > > > > > > > Add kprobe_event= boot parameter to define kprobe events > > > > > at boot time. > > > > > The definition syntax is similar to tracefs/kprobe_events > > > > > interface, but use ',' and ';' instead of ' ' and '\n' > > > > > respectively. e.g. > > > > > > > > > > kprobe_event=p,vfs_read,$arg1,$arg2 > > > > > > > > > > This puts a probe on vfs_read with argument1 and 2, and > > > > > enable the new event. > > > > > > > > > > Signed-off-by: Masami Hiramatsu > > > > > > > > I built an arm64 kernel from todays linux-next tag next-20190528 and > > > > ran in to this issue when I booted it up in qemu: > > Thank you for reporting! > > > > [ 9.020354][ T1] Kprobe smoke test: started > > [ 9.064132][ T1] Internal error: aarch64 BRK: f2000004 [#1] PREEMPT SMP > > [ 9.067084][ T1] Modules linked in: > > [ 9.068772][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted > > 5.2.0-rc2-next-20190528-00019-g9a6008710716 #8 > > [ 9.072893][ T1] Hardware name: linux,dummy-virt (DT) > > [ 9.075143][ T1] pstate: 80400005 (Nzcv daif +PAN -UAO) > > [ 9.077528][ T1] pc : kprobe_target+0x0/0x30 > > [ 9.079479][ T1] lr : init_test_probes+0x134/0x540 > > [ 9.081611][ T1] sp : ffff80003f51fbe0 > > [ 9.083331][ T1] x29: ffff80003f51fbe0 x28: ffff200013c17820 > > [ 9.085906][ T1] x27: ffff200015d3ab40 x26: ffff2000122bb120 > > [ 9.088491][ T1] x25: 0000000000000000 x24: ffff200013c08ae0 > > [ 9.091068][ T1] x23: ffff200015d39000 x22: ffff200013a15ac8 > > [ 9.093667][ T1] x21: 1ffff00007ea3f86 x20: ffff200015d39420 > > [ 9.096214][ T1] x19: ffff2000122bad20 x18: 0000000000001400 > > [ 9.098831][ T1] x17: 0000000000000000 x16: ffff80003f510040 > > [ 9.101410][ T1] x15: 0000000000001480 x14: 1ffff00007ea3ea2 > > [ 9.103963][ T1] x13: 00000000f1f1f1f1 x12: ffff040002782e0d > > [ 9.106549][ T1] x11: 1fffe40002782e0c x10: ffff040002782e0c > > [ 9.109120][ T1] x9 : 1fffe40002782e0c x8 : dfff200000000000 > > [ 9.111676][ T1] x7 : ffff040002782e0d x6 : ffff200013c17067 > > [ 9.114234][ T1] x5 : ffff80003f510040 x4 : 0000000000000000 > > [ 9.116843][ T1] x3 : ffff200010427508 x2 : 0000000000000000 > > [ 9.119409][ T1] x1 : ffff200010426e10 x0 : 0000000000a6326b > > [ 9.121980][ T1] Call trace: > > [ 9.123380][ T1] kprobe_target+0x0/0x30 > > [ 9.125205][ T1] init_kprobes+0x2b8/0x300 > > [ 9.127074][ T1] do_one_initcall+0x4c0/0xa68 > > [ 9.129076][ T1] kernel_init_freeable+0x3c4/0x4e4 > > [ 9.131234][ T1] kernel_init+0x14/0x1fc > > [ 9.133032][ T1] ret_from_fork+0x10/0x18 > > [ 9.134908][ T1] Code: a9446bf9 f9402bfb a8d87bfd d65f03c0 (d4200080) > > [ 9.137845][ T1] ---[ end trace 49243ee03446b072 ]--- > > [ 9.140114][ T1] Kernel panic - not syncing: Fatal exception > > [ 9.142684][ T1] ---[ end Kernel panic - not syncing: Fatal exception ]--- > > Ah, I think you hit this in [1/2], not this change. > > I guess arm64's breakpoint handler is not initialized at postcore_initcall(). > I have to check the arch depend implementation on arm64. Yes, for some reason, arm64 breakpoint handler vector is initalized in arch_initcall(). Let's move init_kprobes to subsys_initcall, which is called before fs_initcall. Thank you, -- Masami Hiramatsu