From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933275AbXA2Iro (ORCPT ); Mon, 29 Jan 2007 03:47:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933277AbXA2Iro (ORCPT ); Mon, 29 Jan 2007 03:47:44 -0500 Received: from cantor.suse.de ([195.135.220.2]:43116 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933275AbXA2IrU (ORCPT ); Mon, 29 Jan 2007 03:47:20 -0500 From: Andi Kleen To: Andrew Morton Subject: Re: [Bugme-new] [Bug 7891] New: vdso page is no longer mapped for Date: Mon, 29 Jan 2007 04:10:29 +0100 User-Agent: KMail/1.9.1 Cc: "Parag Warudkar" , dsd@gentoo.org, joerg@hydrops.han.de, linux-kernel@vger.kernel.org References: <82e4877d0701271201n3aa5bdf6v7c5fb8e41ee98c80@mail.gmail.com> <20070127140233.203ef7d3.akpm@osdl.org> In-Reply-To: <20070127140233.203ef7d3.akpm@osdl.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200701290410.29427.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 27 January 2007 23:02, Andrew Morton wrote: > On Sat, 27 Jan 2007 15:01:51 -0500 > > "Parag Warudkar" wrote: > > Here is a patch that does what Andrew Morton suggested (plus some more > > as explained below) . > > Patch inline below and also attached in case there is whitespace > > damage. Compile tested on i386 with make defconfig; make. If anyone > > can test on other arches and provide feedback that'd be great. > > Thanks - I can test elf on powerpc. Does anyone remember how to > create a.out executables? You need an old toolkit, but the historic section of ftp.funet.fi has a few binaries. I also got a tarball of an old a.out SUSE installation somewhere that I can dig out if there is interest. > Assuming this works, I'm not surew what to do with it. Jam it into > 2.6.20, I guess. The lateness*largeness product is somewhat high though. I simpler fix might be to just not require the vDSO for signal handling on a.out. Here's a untested patch. -Andi Don't require the vDSO for handling a.out signals and in other strange binfmts. vDSO is not necessarily mapped there. Signed-off-by: Andi Kleen Index: linux/arch/i386/kernel/signal.c =================================================================== --- linux.orig/arch/i386/kernel/signal.c +++ linux/arch/i386/kernel/signal.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -349,7 +350,10 @@ static int setup_frame(int sig, struct k goto give_sigsegv; } - restorer = (void *)VDSO_SYM(&__kernel_sigreturn); + if (current->binfmt->hasvdso) + restorer = (void *)VDSO_SYM(&__kernel_sigreturn); + else + restorer = (void *)&frame->retcode; if (ka->sa.sa_flags & SA_RESTORER) restorer = ka->sa.sa_restorer; Index: linux/arch/x86_64/ia32/ia32_signal.c =================================================================== --- linux.orig/arch/x86_64/ia32/ia32_signal.c +++ linux/arch/x86_64/ia32/ia32_signal.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -449,7 +450,11 @@ int ia32_setup_frame(int sig, struct k_s /* Return stub is in 32bit vsyscall page */ { - void __user *restorer = VSYSCALL32_SIGRETURN; + void __user *restorer; + if (current->binfmt->hasvdso) + restorer = VSYSCALL32_SIGRETURN; + else + restorer = (void *)&frame->retcode; if (ka->sa.sa_flags & SA_RESTORER) restorer = ka->sa.sa_restorer; err |= __put_user(ptr_to_compat(restorer), &frame->pretcode); Index: linux/fs/binfmt_elf.c =================================================================== --- linux.orig/fs/binfmt_elf.c +++ linux/fs/binfmt_elf.c @@ -76,7 +76,8 @@ static struct linux_binfmt elf_format = .load_binary = load_elf_binary, .load_shlib = load_elf_library, .core_dump = elf_core_dump, - .min_coredump = ELF_EXEC_PAGESIZE + .min_coredump = ELF_EXEC_PAGESIZE, + .hasvdso = 1 }; #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE) Index: linux/include/linux/binfmts.h =================================================================== --- linux.orig/include/linux/binfmts.h +++ linux/include/linux/binfmts.h @@ -59,6 +59,7 @@ struct linux_binfmt { int (*load_shlib)(struct file *); int (*core_dump)(long signr, struct pt_regs * regs, struct file * file); unsigned long min_coredump; /* minimal dump size */ + int hasvdso; }; extern int register_binfmt(struct linux_binfmt *);