From: Jiri Slaby Subject: [PATCH 1/1] x86: fix text_poke Date: Fri, 25 Apr 2008 15:23:56 +0000 (UTC) Message-ID: <1209343883-7991-1-git-send-email-jirislaby__24542.498359415$1209137078$gmane$org@gmail.com> References: <20080425.021301.193689806.davem@davemloft.net> Cc: torvalds@linux-foundation.org, zdenek.kabelac@gmail.com, rjw@sisk.pl, paulmck@linux.vnet.ibm.com, akpm@linux-foundation.org, linux-ext4@vger.kernel.org, herbert@gondor.apana.org.au, penberg@cs.helsinki.fi, clameter@sgi.com, linux-kernel@vger.kernel.org, Jiri Slaby , Mathieu Desnoyers , Andi Kleen , pageexec@freemail.hu, "H. Peter Anvin" , Jeremy Fitzhardinge , Ingo Molnar To: David Miller Return-path: Received: from smtp.wellnetcz.com ([212.24.148.102]:45082 "EHLO WNmonitoring" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751108AbYDYPXg (ORCPT ); Fri, 25 Apr 2008 11:23:36 -0400 Date: Mon, 28 Apr 2008 02:51:23 +0200 In-Reply-To: <20080425.021301.193689806.davem@davemloft.net> Sender: linux-ext4-owner@vger.kernel.org List-ID: David Miller wrote: > From: Jiri Slaby > Date: Fri, 25 Apr 2008 19:10:37 +0200 > > > I'm going to bisect it, will be back in few hours ;). > > Thanks for all of this hard work and investigation Jiri! Thanks. Bisected mm down to git-x86.patch, bisected git-x86-latest down to x86: enhance DEBUG_RODATA support - alternatives The patch below fixes the problem for me. Comments welcome. The 0xf0 pattern comes from alternatives_smp_lock: text_poke(*ptr, ((unsigned char []){0xf0}), 1); I grepped for it a long time ago, but not in a form of coumpound literal :/. *Never* more :). -- kernel_text_address returns true even for modules which is not wanted in text_poke. Use core_kernel_text instead. This is a regression introduced in e587cadd8f47e202a30712e2906a65a0606d5865 which caused occasionaly crashes after suspend/resume. Signed-off-by: Jiri Slaby CC: Mathieu Desnoyers CC: Andi Kleen CC: pageexec@freemail.hu CC: H. Peter Anvin CC: Jeremy Fitzhardinge CC: Ingo Molnar --- arch/x86/kernel/alternative.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 5412fd7..0b074cb 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -515,7 +515,7 @@ void *__kprobes text_poke(void *addr, const void *opcode, size_t len) BUG_ON(len > sizeof(long)); BUG_ON((((long)addr + len - 1) & ~(sizeof(long) - 1)) - ((long)addr & ~(sizeof(long) - 1))); - if (kernel_text_address((unsigned long)addr)) { + if (core_kernel_text((unsigned long)addr)) { struct page *pages[2] = { virt_to_page(addr), virt_to_page(addr + PAGE_SIZE) }; if (!pages[1]) -- 1.5.4.5