From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: lockdep: WARNING: CPU: 28 PID: 10552 at kernel/lockdep.c:3539 Date: Tue, 25 Jun 2013 18:14:32 -0400 Message-ID: <51CA1648.50706@oracle.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: Sender: trinity-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: mingo@kernel.org, peterz@infradead.org Cc: LKML , trinity@vger.kernel.org Hi all, While fuzzing with trinity inside a KVM tools guest running latest -next kernel, I've stumbled on the following: [ 263.899081] ------------[ cut here ]------------ [ 263.900321] WARNING: CPU: 28 PID: 10552 at kernel/lockdep.c:3539 check_flags+0xe0/0x 220() [ 263.906199] DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled) [ 263.906199] CPU: 28 PID: 10552 Comm: trinity-child28 Tainted: G W 3.10.0-r c7-next-20130625-sasha-00011-g7725abd #1124 [ 263.906199] 0000000000000dd3 ffff880f4d105d78 ffffffff841214dc ffff880f4d105d78 [ 263.906199] ffff880f4d105dc8 ffff880f4d105db8 ffffffff8111bfd7 ffff880f4d105db8 [ 263.906199] ffff880f6a480000 0000000000000000 0000000000000002 0000000000000000 [ 263.906199] Call Trace: [ 263.906199] [] dump_stack+0x52/0x87 [ 263.906199] [] warn_slowpath_common+0x87/0xb0 [ 263.906199] [] warn_slowpath_fmt+0x46/0x50 [ 263.906199] [] check_flags+0xe0/0x220 [ 263.906199] [] lock_acquire+0x88/0x1e0 [ 263.906199] [] ? might_fault+0x53/0xb0 [ 263.906199] [] _raw_spin_lock+0x40/0x80 [ 263.906199] [] ? __fd_install+0x36/0x100 [ 263.906199] [] __fd_install+0x36/0x100 [ 263.906199] [] fd_install+0x25/0x30 [ 263.906199] [] SyS_pipe2+0x8c/0xb0 [ 263.906199] [] ? tracesys+0x7e/0xe2 [ 263.906199] [] SyS_pipe+0x10/0x20 [ 263.906199] [] tracesys+0xdd/0xe2 [ 263.906199] ---[ end trace d5eed34e44345976 ]--- [ 263.906199] possible reason: unannotated irqs-on. [ 263.906199] irq event stamp: 45016 [ 263.906199] hardirqs last enabled at (45015): [] paranoid_restore+0x15/0x70 [ 263.906199] hardirqs last disabled at (45016): [] debug_stack_reset+0x94/0x1c0 [ 263.906199] softirqs last enabled at (44514): [] __do_softirq+0x447/0x4d0 [ 263.906199] softirqs last disabled at (44509): [] irq_exit+0x86/0x120 I've started seeing those after I switched the guest to use 128 vcpus (same as the host). Thanks, Sasha