Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760026AbXHBVFp (ORCPT ); Thu, 2 Aug 2007 17:05:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760829AbXHBVFA (ORCPT ); Thu, 2 Aug 2007 17:05:00 -0400 Received: from saraswathi.solana.com ([198.99.130.12]:43963 "EHLO saraswathi.solana.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758602AbXHBVE7 (ORCPT ); Thu, 2 Aug 2007 17:04:59 -0400 Date: Thu, 2 Aug 2007 17:04:38 -0400 From: Jeff Dike To: Andrew Morton Cc: LKML , uml-devel Subject: [PATCH 4/6] UML - Stop specially protecting kernel stacks Message-ID: <20070802210438.GA11184@c2.user-mode-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3257 Lines: 84 Map all of physical memory as executable to avoid having to change stack protections during fork and exit. unprotect_stack is now called only from MODE_TT code, so it is marked as such. Signed-off-by: Jeff Dike -- arch/um/include/kern_util.h | 2 ++ arch/um/kernel/init_task.c | 2 ++ arch/um/kernel/physmem.c | 2 +- arch/um/kernel/process.c | 5 ++--- 4 files changed, 7 insertions(+), 4 deletions(-) Index: linux-2.6.21-mm/arch/um/kernel/physmem.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/kernel/physmem.c 2007-08-02 16:43:17.000000000 -0400 +++ linux-2.6.21-mm/arch/um/kernel/physmem.c 2007-08-02 16:43:25.000000000 -0400 @@ -105,7 +105,7 @@ void __init setup_physmem(unsigned long offset = uml_reserved - uml_physmem; err = os_map_memory((void *) uml_reserved, physmem_fd, offset, - len - offset, 1, 1, 0); + len - offset, 1, 1, 1); if(err < 0){ os_print_error(err, "Mapping memory"); exit(1); Index: linux-2.6.21-mm/arch/um/kernel/process.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/kernel/process.c 2007-08-02 16:43:17.000000000 -0400 +++ linux-2.6.21-mm/arch/um/kernel/process.c 2007-08-02 16:43:25.000000000 -0400 @@ -82,9 +82,9 @@ unsigned long alloc_stack(int order, int if (atomic) flags = GFP_ATOMIC; page = __get_free_pages(flags, order); - if(page == 0) + if (page == 0) return 0; - stack_protections(page); + return page; } @@ -141,7 +141,6 @@ void release_thread(struct task_struct * void exit_thread(void) { - unprotect_stack((unsigned long) current_thread); } void *get_current(void) Index: linux-2.6.21-mm/arch/um/include/kern_util.h =================================================================== --- linux-2.6.21-mm.orig/arch/um/include/kern_util.h 2007-08-02 16:43:17.000000000 -0400 +++ linux-2.6.21-mm/arch/um/include/kern_util.h 2007-08-02 16:43:25.000000000 -0400 @@ -82,7 +82,9 @@ extern void check_stack_overflow(void *p extern void relay_signal(int sig, union uml_pt_regs *regs); extern int user_context(unsigned long sp); extern void timer_irq(union uml_pt_regs *regs); +#ifdef CONFIG_MODE_TT extern void unprotect_stack(unsigned long stack); +#endif extern void do_uml_exitcalls(void); extern int attach_debugger(int idle_pid, int pid, int stop); extern int config_gdb(char *str); Index: linux-2.6.21-mm/arch/um/kernel/init_task.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/kernel/init_task.c 2007-08-02 16:43:17.000000000 -0400 +++ linux-2.6.21-mm/arch/um/kernel/init_task.c 2007-08-02 16:43:25.000000000 -0400 @@ -47,7 +47,9 @@ union thread_union cpu0_irqstack __attribute__((__section__(".data.init_irqstack"))) = { INIT_THREAD_INFO(init_task) }; +#ifdef CONFIG_MODE_TT void unprotect_stack(unsigned long stack) { os_protect_memory((void *) stack, THREAD_SIZE, 1, 1, 0); } +#endif - 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/