From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756356AbaHHLUk (ORCPT ); Fri, 8 Aug 2014 07:20:40 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:37074 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752889AbaHHLUi (ORCPT ); Fri, 8 Aug 2014 07:20:38 -0400 Message-ID: <53E4B281.5050302@canonical.com> Date: Fri, 08 Aug 2014 13:20:33 +0200 From: Stefan Bader User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: "xen-devel@lists.xensource.com" , Linux Kernel Mailing List CC: Kees Cook , David Vrabel Subject: Xen PV domain regression with KASLR enabled (kernel 3.16) Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="qPbMRIjwqkuoVtU0rIgXTH1exhJeiMUqS" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --qPbMRIjwqkuoVtU0rIgXTH1exhJeiMUqS Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: quoted-printable Unfortunately I have not yet figured out why this happens, but can confir= m by compiling with or without CONFIG_RANDOMIZE_BASE being set that without KA= SLR all is ok, but with it enabled there are issues (actually a dom0 does not eve= n boot as a follow up error). Details can be seen in [1] but basically this is always some portion of a= vmalloc allocation failing after hitting a freshly allocated PTE space no= t being PTE_NONE (usually from a module load triggered by systemd-udevd). In the non-dom0 case this repeats many times but ends in a guest that allows log= in. In the dom0 case there is a more fatal error at some point causing a crash. I have not tried this for a normal PV guest but for dom0 it also does not= help to add "nokaslr" to the kernel command-line. -Stefan 19:35:02 [ 2.547049] ------------[ cut here ]------------ 19:35:02 [ 2.547065] WARNING: CPU: 0 PID: 97 at /build/buildd/linux-3.16.0/mm/vmalloc.c:128 vmap_page_range_noflush+0x2d1= /0x370() 19:35:02 [ 2.547069] Modules linked in: 19:35:02 [ 2.547073] CPU: 0 PID: 97 Comm: systemd-udevd Not tainted 3.16.0-6-generic #11-Ubuntu 19:35:02 [ 2.547077] 0000000000000009 ffff880002defb98 ffffffff81755538 0000000000000000 19:35:02 [ 2.547082] ffff880002defbd0 ffffffff8106bb0d ffff88000400ec88 0000000000000001 19:35:02 [ 2.547086] ffff880002fcfb00 ffffffffc0391000 0000000000000000 ffff880002defbe0 19:35:02 [ 2.547090] Call Trace: 19:35:02 [ 2.547096] [] dump_stack+0x45/0x56 19:35:02 [ 2.547101] [] warn_slowpath_common+0x7d/0xa0 19:35:02 [ 2.547104] [] warn_slowpath_null+0x1a/0x20 19:35:02 [ 2.547108] [] vmap_page_range_noflush+0x2d1/0= x370 19:35:02 [ 2.547112] [] map_vm_area+0x2e/0x40 19:35:02 [ 2.547115] [] __vmalloc_node_range+0x188/0x28= 0 19:35:02 [ 2.547120] [] ? module_alloc_update_bounds+0x= 14/0x70 19:35:02 [ 2.547124] [] ? module_alloc_update_bounds+0x= 14/0x70 19:35:02 [ 2.547129] [] module_alloc+0x74/0xd0 19:35:02 [ 2.547132] [] ? module_alloc_update_bounds+0x= 14/0x70 19:35:02 [ 2.547135] [] module_alloc_update_bounds+0x14= /0x70 19:35:02 [ 2.547146] [] layout_and_allocate+0x74c/0xc70= 19:35:02 [ 2.547149] [] load_module+0xd3/0x1b70 19:35:02 [ 2.547154] [] ? vfs_read+0xf1/0x170 19:35:02 [ 2.547157] [] ? copy_module_from_fd.isra.46+0= x121/0x180 19:35:02 [ 2.547161] [] SyS_finit_module+0x86/0xb0 19:35:02 [ 2.547167] [] tracesys+0xe1/0xe6 19:35:02 [ 2.547169] ---[ end trace 8a5de7fc66e75fe4 ]--- 19:35:02 [ 2.547172] vmalloc: allocation failure, allocated 20480 of 2457= 6 bytes 19:35:02 [ 2.547175] systemd-udevd: page allocation failure: order:0, mod= e:0xd2 [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1350522 --qPbMRIjwqkuoVtU0rIgXTH1exhJeiMUqS Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCgAGBQJT5LKBAAoJEOhnXe7L7s6jAhEP/j9W8Lkw1DguCs4Ojpl+GZrC rrpC4U3hxZP/sJmZb/xzIDVI6U6lh0JBMRGE6tijij/8vpAEKib3y6QUUU9LSL6G s+jlZE6KmwHDI7hCQ5DDGZG8o9IsJPtAfhTKaXHaG0OG1XMDVcmTqJlD9+Mmws8F dYnETEUiI9rmRGf4Xc81L5IwxYe0gK2s3ZA+BqtFR5Kfd42ggkcPj7N7/XUYxEwE wXBIAd6pHVJ5PzvTimBADvpmjsLzq1cuNxlnAYDgrzoeJ1Oc4KVuvKYP/DIEz4o3 g+OXCVvAC+ntjkKmNfYAmYa7/6ch2yRRsnUHQs6kv3soxfHYhgse2vzN/1UtUxtw s4p1kZJKXFruh8VGF1MvJOnUWRNNsanO4/5cyq7QxhFYKsOSH7qeY2Lj5g7ZIZwt VjZVqR8GfQJrREBilHDxqw9HPxoTlAkttz1O11DFj97AS6D770CS8SZPXqR3j0bA z3wGWQN5sJwdti3tA6XdoYejGL9nykgMHZ9xA7NuCWz/FRB7x0zY51fRlnISSjo+ JUIjiHA+Sp+XaB94bPLFBsxBHZLzNefyplMgKm7ZFRCiIbb0P5ssMNUMCR4K2Pfi Jm66DjrzY9afnr2j98iu+6y/fCDqAny+bZhnxQjv/SGwPIO2YOtGii2sBjVNhfFT qzQwft5ZV9P1kMlEYLuK =PEUc -----END PGP SIGNATURE----- --qPbMRIjwqkuoVtU0rIgXTH1exhJeiMUqS--