Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757632AbaGODTf (ORCPT ); Mon, 14 Jul 2014 23:19:35 -0400 Received: from ozlabs.org ([103.22.144.67]:53544 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757402AbaGODTc (ORCPT ); Mon, 14 Jul 2014 23:19:32 -0400 Message-ID: <1405394370.17767.7.camel@concordia> Subject: Re: [PATCH v5 2/2] [BUGFIX] kprobes: Fix "Failed to find blacklist" error on ia64 and ppc64 From: Michael Ellerman To: Masami Hiramatsu Cc: Benjamin Herrenschmidt , Paul Mackerras , Tony Luck , Jeremy Fitzhardinge , linux-ia64@vger.kernel.org, sparse@chrisli.org, "H. Peter Anvin" , Ingo Molnar , linux-tip-commits@vger.kernel.org, akataria@vmware.com, anil.s.keshavamurthy@intel.com, "Suzuki K. Poulose" , Fenghua Yu , Arnd Bergmann , Rusty Russell , Chris Wright , yrl.pp-manager.tt@hitachi.com, Thomas Gleixner , 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: Tue, 15 Jul 2014 13:19:30 +1000 In-Reply-To: <20140702070029.14689.18485.stgit@kbuild-fedora.novalocal> References: <1404276081.7254.1.camel@concordia> <20140702070029.14689.18485.stgit@kbuild-fedora.novalocal> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2014-07-02 at 07:00 +0000, 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 for kallsyms_lookup_size_offset() while initializing > blacklist. > > Changes in v5: > - Use arch_deref_entry_point() instead of function_entry(). > > Changes in v4: > - Add kernel_text_address() check for verifying the address. > - Moved on the latest linus tree. > > Changes in v3: > - Fix a bug to get blacklist address based on function entry > instead of function descriptor. (Suzuki's work, Thanks!) > > Changes in V2: > - Use function_entry() macro when lookin up symbols instead > of storing it. > - Update for the latest -next. > > Signed-off-by: Masami Hiramatsu > Reported-by: Tony Luck > Tested-by: Tony Luck > Cc: Michael Ellerman Tested-by: Michael Ellerman Acked-by: Michael Ellerman (for powerpc) Ben, can you take this in your tree? cheers -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/