From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753004AbaC0Fuu (ORCPT ); Thu, 27 Mar 2014 01:50:50 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:56478 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751595AbaC0Fus (ORCPT ); Thu, 27 Mar 2014 01:50:48 -0400 Message-ID: <5333BC31.3030400@hitachi.com> Date: Thu, 27 Mar 2014 14:50:41 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Andi Kleen , Ananth N Mavinakayanahalli , Sandeepa Prabhu , Frederic Weisbecker , x86@kernel.org, fche@redhat.com, mingo@redhat.com, systemtap@sourceware.org, "H. Peter Anvin" , Thomas Gleixner , Andrew Morton , "yrl.pp-manager.tt@hitachi.com" Subject: Re: Re: [PATCH -tip v8 10/26] kprobes/x86: Allow probe on some kprobe preparation functions References: <20140305115843.22766.8355.stgit@ltc230.yrl.intra.hitachi.co.jp> <20140305115953.22766.53497.stgit@ltc230.yrl.intra.hitachi.co.jp> <20140324153556.2ae6b181@gandalf.local.home> In-Reply-To: <20140324153556.2ae6b181@gandalf.local.home> Content-Type: multipart/mixed; boundary="------------010104060400060805090704" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a multi-part message in MIME format. --------------010104060400060805090704 Content-Type: text/plain; charset=Shift_JIS Content-Transfer-Encoding: 7bit (2014/03/25 4:35), Steven Rostedt wrote: > On Wed, 05 Mar 2014 20:59:53 +0900 > Masami Hiramatsu wrote: > >> There is no need to prohibit probing on the functions >> used in preparation phase. Those are safely probed because >> those are not invoked from breakpoint/fault/debug handlers, >> there is no chance to cause recursive exceptions. >> >> Following functions are now removed from the kprobes blacklist. >> can_boost >> can_probe >> can_optimize >> is_IF_modifier >> __copy_instruction >> copy_optimized_instructions >> arch_copy_kprobe >> arch_prepare_kprobe >> arch_arm_kprobe >> arch_disarm_kprobe >> arch_remove_kprobe > > Is there any possibility that the arm and disarm could cause issues if > we have a probe in the middle of setting it? > > I guess not, but I just wanted to ask, as your test only tested the > start of function and not the middle of it. OK, I've tested it by attached script which adds probes on every address of the target function and run a testcase(register/unregister other probes), and found no problem. :) Thank you, -- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com --------------010104060400060805090704 Content-Type: text/plain; charset=Shift_JIS; name="kprobes_test.sh" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="kprobes_test.sh" IyEvYmluL2Jhc2gNClRBUkdFVFM9JDENCkZUUkFDRV9LUFJPQkVfRVZFTlQ9L3N5cy9rZXJu ZWwvZGVidWcvdHJhY2luZy9rcHJvYmVfZXZlbnRzDQpGVFJBQ0VfS1BST0JFX1BST0ZJTEU9 L3N5cy9rZXJuZWwvZGVidWcvdHJhY2luZy9rcHJvYmVfcHJvZmlsZQ0KRlRSQUNFX0VWRU5U Uz0vc3lzL2tlcm5lbC9kZWJ1Zy90cmFjaW5nL2V2ZW50cw0KDQppZiBbICEgLWYgJFRBUkdF VFMgXTsgdGhlbg0KICBlY2hvICJVc2FnZToga3Byb2JlX3Rlc3Quc2ggPFRhcmdldGZpbGU+ Ig0KICBleGl0IDENCmZpDQppZiBbIGBpZCAtdWAgLW5lIDAgXTsgdGhlbg0KICBlY2hvICJF cnJvcjogVGhpcyBwcm9ncmFtIHJlcXVpcmVzIHJvb3QgcHJpdmlsZWdlIg0KICBleGl0IDIN CmZpDQoNCmZ1bmN0aW9uIGdldF9zeW1ib2xfc2l6ZSgpIHsgI3N5bWJvbA0KZ3JlcCAkMSAt dyAtbTEgLUExIC9wcm9jL2thbGxzeW1zIHxcDQogYXdrICdCRUdJTnsgcyA9IDAgfTsge3Ag PSBzdHJ0b251bSgiMHgic3Vic3RyKCQxLDksOCkpOyBpZiAocyA9PSAwKSB7cyA9IHA7fSBl bHNlIHsgcHJpbnQgcCAtIHN9fScNCn0NCg0KZnVuY3Rpb24gc2V0dXBfcHJvYmVzKCkgeyAj c3ltYm9sDQpzaXplPWBnZXRfc3ltYm9sX3NpemUgJDFgDQppZiBbIC16ICIkc2l6ZSIgXTsg dGhlbg0KICBlY2hvICJObyBzeW1ib2wgJDEgZm91bmQiDQogIHJldHVybiAxDQpmaQ0KaT0w DQplcnI9MA0Kd2hpbGUgWyAkaSAtbHQgJHNpemUgXTsgZG8NCiAgKGVjaG8gcCAkMSskaSAg Pj4gJEZUUkFDRV9LUFJPQkVfRVZFTlQpICY+IC9kZXYvbnVsbA0KICBbICQ/IC1lcSAwIF0g fHwgZXJyPSQoKGVycisxKSkNCiAgaT0kKChpKzEpKQ0KZG9uZQ0KcHJvYmVkPWBleHByICRz aXplIC0gJGVycmANCmVjaG8gIlNldHVwICRwcm9iZWQgcHJvYmVzIG9uICQxIg0KWyAkcHJv YmVkIC1lcSAwIF0gJiYgcmV0dXJuIDENCnJldHVybiAwDQp9DQoNCmZ1bmN0aW9uIGVuYWJs ZV9wcm9iZXMoKSB7DQplY2hvIDEgPiAkRlRSQUNFX0VWRU5UUy9rcHJvYmVzL2VuYWJsZQ0K fQ0KDQpmdW5jdGlvbiBjbGVhcl9wcm9iZXMoKSB7DQplY2hvIDAgPiAkRlRSQUNFX0VWRU5U Uy9rcHJvYmVzL2VuYWJsZQ0KZWNobyA+ICRGVFJBQ0VfS1BST0JFX0VWRU5UDQp9DQoNCmZ1 bmN0aW9uIHJ1bl90ZXN0KCkgew0KZWNobyBwOnRlc3QxIHZmc19zeW1saW5rID4+ICRGVFJB Q0VfS1BST0JFX0VWRU5UDQplY2hvIHA6dGVzdDIgdmZzX3N5bWxpbmsrNSA+PiAkRlRSQUNF X0tQUk9CRV9FVkVOVA0KZWNobyAxID4gJEZUUkFDRV9FVkVOVFMva3Byb2Jlcy90ZXN0MS9l bmFibGUNCmVjaG8gMSA+ICRGVFJBQ0VfRVZFTlRTL2twcm9iZXMvdGVzdDIvZW5hYmxlDQpz bGVlcCAxDQplY2hvIDAgPiAkRlRSQUNFX0VWRU5UUy9rcHJvYmVzL3Rlc3QxL2VuYWJsZQ0K ZWNobyAwID4gJEZUUkFDRV9FVkVOVFMva3Byb2Jlcy90ZXN0Mi9lbmFibGUNCmVjaG8gLTp0 ZXN0MSA+PiAkRlRSQUNFX0tQUk9CRV9FVkVOVA0KZWNobyAtOnRlc3QyID4+ICRGVFJBQ0Vf S1BST0JFX0VWRU5UDQp9DQoNCmZ1bmN0aW9uIHNhdmVfcHJvZmlsZSgpIHsgIyBzeW1ib2wN CmNhdCAkRlRSQUNFX0tQUk9CRV9QUk9GSUxFID4gJHsxfS5wcm9maWxlDQp9DQoNCmZ1bmN0 aW9uIHRlc3Rfb24oKSB7ICMgc3ltYm9sDQpzZXR1cF9wcm9iZXMgJDENClsgJD8gLW5lIDAg XSAmJiByZXR1cm4NCmVuYWJsZV9wcm9iZXMNCmVjaG8gIlByb2JlIEVuYWJsZWQiDQpydW5f dGVzdA0KZWNobyAiVGVzdCBkb25lIG9uICQxIg0Kc2F2ZV9wcm9maWxlICQxDQpjbGVhcl9w cm9iZXMNCn0NCg0KY2xlYXJfcHJvYmVzDQpjYXQgJFRBUkdFVFMgfCB3aGlsZSByZWFkIHN5 bTsgZG8NCiAgdGVzdF9vbiAkc3ltDQpkb25lDQoNCg== --------------010104060400060805090704--