From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753343AbcFJVX2 (ORCPT ); Fri, 10 Jun 2016 17:23:28 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:55535 "HELO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753208AbcFJVX1 (ORCPT ); Fri, 10 Jun 2016 17:23:27 -0400 From: "Rafael J. Wysocki" To: Kees Cook Cc: Logan Gunthorpe , "Rafael J. Wysocki" , Stephen Smalley , Ingo Molnar , Ingo Molnar , the arch/x86 maintainers , "linux-pm@vger.kernel.org" , Linux Kernel Mailing List , Andy Lutomirski , Borislav Petkov , Denys Vlasenko , Brian Gerst Subject: Re: PROBLEM: Resume form hibernate broken by setting NX on gap Date: Fri, 10 Jun 2016 23:27:29 +0200 Message-ID: <34107887.ATgOLutrT1@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/4.5.0-rc1+; KDE/4.11.5; x86_64; ; ) In-Reply-To: References: <573DF82D.50006@deltatee.com> <575A3E95.5090100@deltatee.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday, June 10, 2016 11:09:22 AM Kees Cook wrote: > On Thu, Jun 9, 2016 at 9:14 PM, Logan Gunthorpe wrote: > > Hey, > > > > I've still be trying to figure this out as I have time. > > > > I tried printing a couple restore addresses and nothing I can find seems > > anywhere near the rodata/ex_table boundary. > > > > I tried with the (badly formatted) below and got the following. Nothing too > > surprising. I've attached a kallsyms that matches the kernel for reference. > > > > restore_code: ffff880157c3b000 > > jump_addr: ffffffff81446be0 > > > > > > diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c > > index 009947d..6efedb7 100644 > > --- a/arch/x86/power/hibernate_64.c > > +++ b/arch/x86/power/hibernate_64.c > > @@ -92,6 +92,9 @@ int swsusp_arch_resume(void) > > memcpy(relocated_restore_code, &core_restore_code, > > &restore_registers - &core_restore_code); > > > > + pr_info("restore_code: %p\n", relocated_restore_code); > > + pr_info("jump_addr: %lx\n", restore_jump_address); > > + > > Also interesting would be the "relocated_restore_code" address, as > well as a dump of /sys/kernel/debug/kernel_page_tables (from > CONFIG_X86_PTDUMP). > > I'm baffled by the problem, but the best I can understand is the the > relocated_restore_code range isn't executable (which should be visible > from finding it in /sys/kernel/debug/kernel_page_tables), but I don't > see how to solve that since my original patch didn't work. > > Rafael, is this something you have time to look at quickly? Well, not really, but I'll do my best to look at it in the next few days. Thanks, Rafael