Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932850AbbLPMCh (ORCPT ); Wed, 16 Dec 2015 07:02:37 -0500 Received: from mx2.suse.de ([195.135.220.15]:56373 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752471AbbLPMCf (ORCPT ); Wed, 16 Dec 2015 07:02:35 -0500 Date: Wed, 16 Dec 2015 13:02:32 +0100 (CET) From: Miroslav Benes To: Jessica Yu cc: Rusty Russell , Josh Poimboeuf , Seth Jennings , Jiri Kosina , Vojtech Pavlik , Jonathan Corbet , linux-api@vger.kernel.org, live-patching@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [RFC PATCH v2 3/6] module: s390: keep mod_arch_specific for livepatch modules In-Reply-To: <1448943679-3412-4-git-send-email-jeyu@redhat.com> Message-ID: References: <1448943679-3412-1-git-send-email-jeyu@redhat.com> <1448943679-3412-4-git-send-email-jeyu@redhat.com> User-Agent: Alpine 2.00 (LNX 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2269 Lines: 70 On Mon, 30 Nov 2015, Jessica Yu wrote: > Livepatch needs to utilize the symbol information contained in the > mod_arch_specific struct in order to be able to call the s390 > apply_relocate_add() function to apply relocations. Remove the redundant > vfree() in module_finalize() since module_arch_freeing_init() (which also frees > said structures) is called in do_init_module(). Keep a reference to syminfo if > the module is a livepatch module and free the structures in > module_arch_cleanup(). If the module isn't a livepatch module, we free the > structures in module_arch_freeing_init() as usual. > > Signed-off-by: Jessica Yu > --- > arch/s390/kernel/module.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c > index 0c1a679..17a1979 100644 > --- a/arch/s390/kernel/module.c > +++ b/arch/s390/kernel/module.c > @@ -51,6 +51,9 @@ void *module_alloc(unsigned long size) > > void module_arch_freeing_init(struct module *mod) > { > + if (mod->klp) > + return; > + > vfree(mod->arch.syminfo); > mod->arch.syminfo = NULL; > } Hm, this is problematic. module_arch_freeing_init() is called from module_deallocate() and this is called in the error path in load_module(). So if there was an error during load_module() of livepatch module which led to free_modinfo label or behind mod->arch.syminfo would not be freed at all. module_arch_cleanup() is called earlier under free_arch_cleanup. Miroslav > @@ -420,12 +423,18 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, > return 0; > } > > +void module_arch_cleanup(struct module *mod) > +{ > + if (mod->klp) { > + vfree(mod->arch.syminfo); > + mod->arch.syminfo = NULL; > + } > +} > + > int module_finalize(const Elf_Ehdr *hdr, > const Elf_Shdr *sechdrs, > struct module *me) > { > jump_label_apply_nops(me); > - vfree(me->arch.syminfo); > - me->arch.syminfo = NULL; > return 0; > } > -- > 2.4.3 > -- 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/