From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965274AbaFRIrK (ORCPT ); Wed, 18 Jun 2014 04:47:10 -0400 Received: from mail4.hitachi.co.jp ([133.145.228.5]:39746 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965156AbaFRIrG (ORCPT ); Wed, 18 Jun 2014 04:47:06 -0400 Message-ID: <53A15201.7060404@hitachi.com> Date: Wed, 18 Jun 2014 17:46:57 +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: Michael Ellerman Cc: Benjamin Herrenschmidt , "Suzuki K. Poulose" , 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: [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> In-Reply-To: <1403078179.32307.7.camel@concordia> 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 (2014/06/18 16:56), Michael Ellerman wrote: > On Fri, 2014-06-06 at 15:38 +0900, Masami Hiramatsu wrote: >> Ping? >> >> I guess this should go to 3.16 branch, shouldn't it? > >>> diff --git a/arch/powerpc/include/asm/types.h b/arch/powerpc/include/asm/types.h >>> index bfb6ded..8b89d65 100644 >>> --- a/arch/powerpc/include/asm/types.h >>> +++ b/arch/powerpc/include/asm/types.h >>> @@ -25,6 +25,17 @@ typedef struct { >>> unsigned long env; >>> } func_descr_t; >>> >>> +#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF == 1) >>> +/* >>> + * On PPC64 ABIv1 the function pointer actually points to the >>> + * function's descriptor. The first entry in the descriptor is the >>> + * address of the function text. >>> + */ >>> +#define function_entry(fn) (((func_descr_t *)(fn))->entry) >>> +#else >>> +#define function_entry(fn) ((unsigned long)(fn)) >>> +#endif > > We already have ppc_function_entry(), can't you use that? I'd like to ask you whether the address which ppc_function_entry() returns on PPC ABIv2 is really same address in kallsyms or not. As you can see, kprobes uses function_entry() to get the actual entry address where kallsyms knows. I have not much information about that, but it seems that the "global entry point" is the address which kallsyms knows, isn't it? Thank you, -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com