From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932868AbaEPPfS (ORCPT ); Fri, 16 May 2014 11:35:18 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:37869 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932509AbaEPPfQ (ORCPT ); Fri, 16 May 2014 11:35:16 -0400 Date: Fri, 16 May 2014 17:34:55 +0200 From: Peter Zijlstra To: Sasha Levin Cc: Ingo Molnar , acme@ghostprotocols.net, LKML , Thomas Gleixner , Dave Jones , hpa@linux.intel.com, tytso@mit.edu, price@mit.edu, hannes@stressinduktion.org Subject: BUG_ON drivers/char/random.c:986 (Was: perf: use after free in perf_remove_from_context) Message-ID: <20140516153455.GV11096@twins.programming.kicks-ass.net> References: <5370EBE9.6@oracle.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="qzBiUkG7YMMDZbZI" Content-Disposition: inline In-Reply-To: <5370EBE9.6@oracle.com> User-Agent: Mutt/1.5.21 (2012-12-30) X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --qzBiUkG7YMMDZbZI Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable While fuzzing to reproduce my issue I hit the below, its triggered loads of times and then the machine wedged (needed a power cycle), I can provide the full console log if people care. Anybody seen that one before? --- [ 861.777414] ------------[ cut here ]------------ [ 861.777416] kernel BUG at /usr/src/linux-2.6/drivers/char/random.c:986! [ 861.777419] invalid opcode: 0000 [#1] PREEMPT SMP=20 [ 861.777421] Modules linked in: [ 861.777424] CPU: 1 PID: 9851 Comm: trinity-c321 Not tainted 3.15.0-rc5-0= 1700-g505011124ad0-dirty #1076 [ 861.777425] Hardware name: Supermicro X8DTN/X8DTN, BIOS 4.6.3 01/08/2010 [ 861.777426] task: ffff88022f68a600 ti: ffff88022f716000 task.ti: ffff880= 22f716000 [ 861.777433] RIP: 0010:[] [] account= +0x164/0x170 [ 861.777434] RSP: 0000:ffff88022f717e48 EFLAGS: 00010202 [ 861.777435] RAX: ffffffff81c90788 RBX: 0000000000000991 RCX: 00000000000= 00000 [ 861.777436] RDX: 0000000000000000 RSI: 0000000000000991 RDI: 00000000000= 02000 [ 861.777437] RBP: ffff88022f717e70 R08: 0000000000000000 R09: 00000000000= 00000 [ 861.777438] R10: 00000000000046c0 R11: 000000c8a18b27e1 R12: ffffffff81c= 90300 [ 861.777439] R13: 0000000000000000 R14: ffffffff8142aff6 R15: ffffffff81a= 58605 [ 861.777441] FS: 00007fba327ff700(0000) GS:ffff880237c20000(0000) knlGS:= 0000000000000000 [ 861.777442] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 861.777443] CR2: 0000000000000010 CR3: 000000022f703000 CR4: 00000000000= 007e0 [ 861.777444] Stack: [ 861.777446] 0000000000000991 0000000000007b44 0000000000000000 ffffffff= 8142aff6 [ 861.777448] ffffffff81a58605 ffff88022f717ed0 ffffffff8142ae82 00000000= 00000000 [ 861.777450] ffffffff81c90300 0000000000020000 ffff880233291240 ffff8804= 35788690 [ 861.777451] Call Trace: [ 861.777454] [] ? urandom_read+0x46/0x120 [ 861.777455] [] extract_entropy_user+0x52/0x180 [ 861.777457] [] urandom_read+0x46/0x120 [ 861.777462] [] vfs_read+0xab/0x180 [ 861.777464] [] SyS_read+0x52/0xb0 [ 861.777466] [] ia32_do_call+0x13/0x13 [ 861.777489] Code: c9 81 e8 a0 5e cb ff ba 02 00 02 00 be 1d 00 00 00 48 = c7 c7 c0 e5 c6 82 e8 9a 64 db ff 48 89 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 = <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5=20 [ 861.777491] RIP [] account+0x164/0x170 [ 861.777492] RSP [ 861.778140] ---[ end trace e70cc3dc70339c62 ]--- [ 861.779282] ------------[ cut here ]------------ --qzBiUkG7YMMDZbZI Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJTdjAfAAoJEHZH4aRLwOS6qBIP/0k+GJ1x9BkZdqb2HFrc4XP4 Vhsa2Hohbj2bIqgU6eNUKVbNKVxb/i2N5tcip6FU7a7ptVAOwJQ1UwUvnGAHdpuf tYlEkYZPNOJ/3Z9Z+YsFF+2TxE5CYgT2fnsMnuUPqurJmajdfje+JMtK3DMFBmsP wDVqFsfHCF9dkARo2YRDFuf4pP9vGzRVyLbhaqwVJ+T48vMho5jv15SFppAZp4o5 r01IvknRUNTxSk0IaKqDMztRHhlZlvRIZQooQ0DaJliLbCi2wPMP+x1u52/PWd2E EJXb/6NCoSmncq0h88l6iPBdM5DriZVE84Ba+sOWZRxtWVe04r4wwU4ba6xbGswR /rMgDfDxiIrm7y3agch+Z8T+VfxTMODQQ+uQ7URSICgNBELqq/EORW4VV2OnErUs k4bP0LA7yGZ/vm+LMMsz+NOxgUxh8ZXPEb15ZxHNHFDn4Brzzusw9bAy0bbsFjlK GPHO0FJbB6dxOuCejNse32hKF9dHCwMQrsmkR8YC4+oLUgqctZoYqiYkTn9+Vwzd ShsJXTUILUBoovixgJKAszro5680s/cR7QxJgXelGh8ANobUoUMXa86vZjBctJ+A cX8O2raZhAgaGLoUL++UO5OqHwl+4s60ybVh2ke6AZqJhvS1NxGMeP7S28a9S5f8 xcETmVNe3rLTBY4yVC2z =Czc+ -----END PGP SIGNATURE----- --qzBiUkG7YMMDZbZI--