From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932715AbaEGL70 (ORCPT ); Wed, 7 May 2014 07:59:26 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:56609 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755840AbaEGL7W (ORCPT ); Wed, 7 May 2014 07:59:22 -0400 Message-ID: <536A2013.8020609@hitachi.com> Date: Wed, 07 May 2014 20:59:15 +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: Benjamin Herrenschmidt , Paul Mackerras , Tony Luck Cc: 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 , Ananth N Mavinakayanahalli , linuxppc-dev@lists.ozlabs.org, rdunlap@infradead.org, Linux Kernel Mailing List , dl9pf@gmx.de, Andrew Morton , Linus Torvalds , "David S. Miller" Subject: Re: [RFT PATCH -next ] [BUGFIX] kprobes: Fix "Failed to find blacklist" error on ia64 and ppc64 References: <536A16A6.5040709@hitachi.com> <20140507115551.22259.70581.stgit@ltc230.yrl.intra.hitachi.co.jp> In-Reply-To: <20140507115551.22259.70581.stgit@ltc230.yrl.intra.hitachi.co.jp> 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 Hi Tony, Benjamin and Paul, I've tried to fix this bug, but since I don't have either ppc64 nor ia64, this patch is not tested on those archs. Please review and test it on those machines. Thank you, (2014/05/07 20:55), Masami Hiramatsu wrote: > On ia64 and ppc64, the function pointer does not point the > entry address of the function, but the address of function > discriptor (which contains the entry address and misc > data.) Since the kprobes passes the function pointer stored > by NOKPROBE_SYMBOL() to kallsyms_lookup_size_offset() for > initalizing its blacklist, it fails and reports many errors > as below. > > Failed to find blacklist 0001013168300000 > Failed to find blacklist 0001013000f0a000 > Failed to find blacklist 000101315f70a000 > Failed to find blacklist 000101324c80a000 > Failed to find blacklist 0001013063f0a000 > Failed to find blacklist 000101327800a000 > Failed to find blacklist 0001013277f0a000 > Failed to find blacklist 000101315a70a000 > Failed to find blacklist 0001013277e0a000 > Failed to find blacklist 000101305a20a000 > Failed to find blacklist 0001013277d0a000 > Failed to find blacklist 00010130bdc0a000 > Failed to find blacklist 00010130dc20a000 > Failed to find blacklist 000101309a00a000 > Failed to find blacklist 0001013277c0a000 > Failed to find blacklist 0001013277b0a000 > Failed to find blacklist 0001013277a0a000 > Failed to find blacklist 000101327790a000 > Failed to find blacklist 000101303140a000 > Failed to find blacklist 0001013a3280a000 > > To fix this bug, this introduces function_entry() macro to > retrieve the entry address from the given function pointer, > and uses it in NOKPROBE_SYMBOL(). > > > Signed-off-by: Masami Hiramatsu > Reported-by: Tony Luck > Cc: Tony Luck > Cc: Fenghua Yu > Cc: Benjamin Herrenschmidt > Cc: Paul Mackerras > Cc: Ananth N Mavinakayanahalli > Cc: Kevin Hao > Cc: linux-ia64@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: linuxppc-dev@lists.ozlabs.org > --- > arch/ia64/include/asm/types.h | 2 ++ > arch/powerpc/include/asm/types.h | 11 +++++++++++ > include/linux/kprobes.h | 3 ++- > include/linux/types.h | 4 ++++ > 4 files changed, 19 insertions(+), 1 deletion(-) > > diff --git a/arch/ia64/include/asm/types.h b/arch/ia64/include/asm/types.h > index 4c351b1..6ab7b6c 100644 > --- a/arch/ia64/include/asm/types.h > +++ b/arch/ia64/include/asm/types.h > @@ -27,5 +27,7 @@ struct fnptr { > unsigned long gp; > }; > > +#define constant_function_entry(fn) (((struct fnptr *)(fn))->ip) > + > #endif /* !__ASSEMBLY__ */ > #endif /* _ASM_IA64_TYPES_H */ > diff --git a/arch/powerpc/include/asm/types.h b/arch/powerpc/include/asm/types.h > index bfb6ded..fd297b8 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 constant_function_entry(fn) (((func_descr_t *)(fn))->entry) > +#else > +#define constant_function_entry(fn) ((unsigned long)(fn)) > +#endif > + > #endif /* __ASSEMBLY__ */ > > #endif /* _ASM_POWERPC_TYPES_H */ > diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h > index e059507..637eafe 100644 > --- a/include/linux/kprobes.h > +++ b/include/linux/kprobes.h > @@ -40,6 +40,7 @@ > #include > #include > #include > +#include > > #ifdef CONFIG_KPROBES > #include > @@ -485,7 +486,7 @@ static inline int enable_jprobe(struct jprobe *jp) > #define __NOKPROBE_SYMBOL(fname) \ > static unsigned long __used \ > __attribute__((section("_kprobe_blacklist"))) \ > - _kbl_addr_##fname = (unsigned long)fname; > + _kbl_addr_##fname = constant_function_entry(fname); > #define NOKPROBE_SYMBOL(fname) __NOKPROBE_SYMBOL(fname) > #else > #define NOKPROBE_SYMBOL(fname) > diff --git a/include/linux/types.h b/include/linux/types.h > index 4d118ba..78e2d7d 100644 > --- a/include/linux/types.h > +++ b/include/linux/types.h > @@ -212,5 +212,9 @@ struct callback_head { > }; > #define rcu_head callback_head > > +#ifndef constant_function_entry > +#define constant_function_entry(fn) ((unsigned long)(fn)) > +#endif > + > #endif /* __ASSEMBLY__ */ > #endif /* _LINUX_TYPES_H */ > > > -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@hitachi.com