From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757691AbaFSLU6 (ORCPT ); Thu, 19 Jun 2014 07:20:58 -0400 Received: from mail4.hitachi.co.jp ([133.145.228.5]:40971 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753129AbaFSLUz (ORCPT ); Thu, 19 Jun 2014 07:20:55 -0400 Message-ID: <53A2C78D.9060708@hitachi.com> Date: Thu, 19 Jun 2014 20:20:45 +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: "Suzuki K. Poulose" Cc: Michael Ellerman , Benjamin Herrenschmidt , Tony Luck , Paul Mackerras , Jeremy Fitzhardinge , linux-ia64@vger.kernel.org, sparse@chrisli.org, "H. Peter Anvin" , Thomas Gleixner , linux-tip-commits@vger.kernel.org, anil.s.keshavamurthy@intel.com, Ingo Molnar , Fenghua Yu , Arnd Bergmann , Rusty Russell , Chris Wright , yrl.pp-manager.tt@hitachi.com, akataria@vmware.com, Tony Luck , Kevin Hao , Linus Torvalds , rdunlap@infradead.org, Linux Kernel Mailing List , dl9pf@gmx.de, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" Subject: Re: Re: Re: [RFT PATCH -next v3] [BUGFIX] kprobes: Fix "Failed to find blacklist" error on ia64 and ppc64 References: <5387F150.5000307@hitachi.com> <20140530031838.17427.75896.stgit@ltc230.yrl.intra.hitachi.co.jp> <539161D6.7020508@hitachi.com> <1403078179.32307.7.camel@concordia> <53A15201.7060404@hitachi.com> <1403141433.4768.1.camel@concordia> <53A26C99.6060000@hitachi.com> <53A285D0.1030106@in.ibm.com> <53A2908E.2000806@hitachi.com> <53A2B136.108@in.ibm.com> <53A2C315.9030006@hitachi.com> In-Reply-To: <53A2C315.9030006@hitachi.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (2014/06/19 20:01), Masami Hiramatsu wrote: >>>>> Ah, those messages should be shown in dmesg when booting if it doesn't work, >>>>> because the messages are printed by initialization process of kprobe blacklist. >>>>> So, reproducing it is just enabling CONFIG_KPROBES and boot it. >>>> Well, we don't get those messages on Power, since the kallsyms has the >>>> entries for ".function_name". The correct way to verify is, either : >>> >>> Hmm, that seems another issue on powerpc. Is that expected(and designed) >>> behavior? >> AFAIK, yes, it is. >> To be more precise : >> >> we have 'foo' and '.foo' for a function foo(), where 'foo' points to the >> function_entry and '.foo' points to the actual function. > > Ah, I see. So if we run > > func_ptr p = foo; > return p == kallsyms_lookup_name(".foo"); > > it returns true. One more thing I should know, is the address of ".function_name" within the kernel text? In other words, does kernel_text_address() return true for that address? If not, it's easy to verify the address. Thank you, -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail4.hitachi.co.jp (mail4.hitachi.co.jp [133.145.228.5]) by lists.ozlabs.org (Postfix) with ESMTP id 127511A0383 for ; Thu, 19 Jun 2014 21:20:54 +1000 (EST) Message-ID: <53A2C78D.9060708@hitachi.com> Date: Thu, 19 Jun 2014 20:20:45 +0900 From: Masami Hiramatsu MIME-Version: 1.0 To: "Suzuki K. Poulose" Subject: Re: Re: Re: [RFT PATCH -next v3] [BUGFIX] kprobes: Fix "Failed to find blacklist" error on ia64 and ppc64 References: <5387F150.5000307@hitachi.com> <20140530031838.17427.75896.stgit@ltc230.yrl.intra.hitachi.co.jp> <539161D6.7020508@hitachi.com> <1403078179.32307.7.camel@concordia> <53A15201.7060404@hitachi.com> <1403141433.4768.1.camel@concordia> <53A26C99.6060000@hitachi.com> <53A285D0.1030106@in.ibm.com> <53A2908E.2000806@hitachi.com> <53A2B136.108@in.ibm.com> <53A2C315.9030006@hitachi.com> In-Reply-To: <53A2C315.9030006@hitachi.com> Content-Type: text/plain; charset=UTF-8 Cc: Jeremy Fitzhardinge , linux-ia64@vger.kernel.org, sparse@chrisli.org, Linux Kernel Mailing List , Paul Mackerras , "H. Peter Anvin" , Thomas Gleixner , linux-tip-commits@vger.kernel.org, anil.s.keshavamurthy@intel.com, Ingo Molnar , Fenghua Yu , Arnd Bergmann , Rusty Russell , Chris Wright , yrl.pp-manager.tt@hitachi.com, akataria@vmware.com, Tony Luck , Kevin Hao , linuxppc-dev@lists.ozlabs.org, rdunlap@infradead.org, Tony Luck , dl9pf@gmx.de, Andrew Morton , Linus Torvalds , "David S. Miller" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , (2014/06/19 20:01), Masami Hiramatsu wrote: >>>>> Ah, those messages should be shown in dmesg when booting if it doesn't work, >>>>> because the messages are printed by initialization process of kprobe blacklist. >>>>> So, reproducing it is just enabling CONFIG_KPROBES and boot it. >>>> Well, we don't get those messages on Power, since the kallsyms has the >>>> entries for ".function_name". The correct way to verify is, either : >>> >>> Hmm, that seems another issue on powerpc. Is that expected(and designed) >>> behavior? >> AFAIK, yes, it is. >> To be more precise : >> >> we have 'foo' and '.foo' for a function foo(), where 'foo' points to the >> function_entry and '.foo' points to the actual function. > > Ah, I see. So if we run > > func_ptr p = foo; > return p == kallsyms_lookup_name(".foo"); > > it returns true. One more thing I should know, is the address of ".function_name" within the kernel text? In other words, does kernel_text_address() return true for that address? If not, it's easy to verify the address. Thank you, -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masami Hiramatsu Date: Thu, 19 Jun 2014 11:20:45 +0000 Subject: Re: Re: Re: [RFT PATCH -next v3] [BUGFIX] kprobes: Fix "Failed to find blacklist" error on ia64 and Message-Id: <53A2C78D.9060708@hitachi.com> List-Id: References: <5387F150.5000307@hitachi.com> <20140530031838.17427.75896.stgit@ltc230.yrl.intra.hitachi.co.jp> <539161D6.7020508@hitachi.com> <1403078179.32307.7.camel@concordia> <53A15201.7060404@hitachi.com> <1403141433.4768.1.camel@concordia> <53A26C99.6060000@hitachi.com> <53A285D0.1030106@in.ibm.com> <53A2908E.2000806@hitachi.com> <53A2B136.108@in.ibm.com> <53A2C315.9030006@hitachi.com> In-Reply-To: <53A2C315.9030006@hitachi.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Suzuki K. Poulose" Cc: Michael Ellerman , Benjamin Herrenschmidt , Tony Luck , Paul Mackerras , Jeremy Fitzhardinge , linux-ia64@vger.kernel.org, sparse@chrisli.org, "H. Peter Anvin" , Thomas Gleixner , linux-tip-commits@vger.kernel.org, anil.s.keshavamurthy@intel.com, Ingo Molnar , Fenghua Yu , Arnd Bergmann , Rusty Russell , Chris Wright , yrl.pp-manager.tt@hitachi.com, akataria@vmware.com, Tony Luck , Kevin Hao , Linus Torvalds , rdunlap@infradead.org, Linux Kernel Mailing List , dl9pf@gmx.de, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" (2014/06/19 20:01), Masami Hiramatsu wrote: >>>>> Ah, those messages should be shown in dmesg when booting if it doesn't work, >>>>> because the messages are printed by initialization process of kprobe blacklist. >>>>> So, reproducing it is just enabling CONFIG_KPROBES and boot it. >>>> Well, we don't get those messages on Power, since the kallsyms has the >>>> entries for ".function_name". The correct way to verify is, either : >>> >>> Hmm, that seems another issue on powerpc. Is that expected(and designed) >>> behavior? >> AFAIK, yes, it is. >> To be more precise : >> >> we have 'foo' and '.foo' for a function foo(), where 'foo' points to the >> function_entry and '.foo' points to the actual function. > > Ah, I see. So if we run > > func_ptr p = foo; > return p = kallsyms_lookup_name(".foo"); > > it returns true. One more thing I should know, is the address of ".function_name" within the kernel text? In other words, does kernel_text_address() return true for that address? If not, it's easy to verify the address. Thank you, -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com