From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932698AbaEGL4E (ORCPT ); Wed, 7 May 2014 07:56:04 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:56347 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755364AbaEGL4B (ORCPT ); Wed, 7 May 2014 07:56:01 -0400 Subject: [RFT PATCH -next ] [BUGFIX] kprobes: Fix "Failed to find blacklist" error on ia64 and ppc64 From: Masami Hiramatsu 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" Date: Wed, 07 May 2014 20:55:51 +0900 Message-ID: <20140507115551.22259.70581.stgit@ltc230.yrl.intra.hitachi.co.jp> In-Reply-To: <536A16A6.5040709@hitachi.com> References: <536A16A6.5040709@hitachi.com> User-Agent: StGit/0.17-dirty MIME-Version: 1.0 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 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 */