Greetings, FYI, a lockdep warning: [ 293.123508] CPA self-test: [ 293.156399] 4k 3069 large 61 gb 0 x 3130[c0000000-cfffc000] miss 0 [ 321.719166] 4k 65533 large 0 gb 0 x 65533[c0000000-cfffc000] miss 0 [ 326.089755] ------------[ cut here ]------------ [ 326.089755] WARNING: at /c/kernel-tests/src/linux/kernel/lockdep.c:3493 check_flags+0xaa/0x190() [ 326.089755] Hardware name: Bochs [ 326.089755] Pid: 8, comm: rcu_kthread Not tainted 3.6.0-rc1 #3 [ 326.089755] Call Trace: [ 326.089755] [] warn_slowpath_common+0x7a/0xa0 [ 326.089755] [] ? check_flags+0xaa/0x190 [ 326.089755] [] ? check_flags+0xaa/0x190 [ 326.089755] [] warn_slowpath_null+0x1d/0x20 [ 326.089755] [] check_flags+0xaa/0x190 [ 326.089755] [] lock_is_held+0x34/0xb0 [ 326.089755] [] __might_sleep+0x31/0x1a0 [ 326.089755] [] ? debug_rt_mutex_init+0x1a/0x30 [ 326.089755] [] rt_mutex_lock+0x1a/0x40 [ 326.089755] [] rcu_kthread+0xea/0x1a0 [ 326.089755] [] ? __rcu_process_callbacks+0xd0/0xd0 [ 326.089755] [] kthread+0x67/0x70 [ 326.089755] [] ? insert_kthread_work+0x80/0x80 [ 326.089755] [] kernel_thread_helper+0x6/0xd [ 326.089755] ---[ end trace c73785c318dc0a8f ]--- [ 326.089755] possible reason: unannotated irqs-on. [ 326.089755] irq event stamp: 440724 [ 326.089755] hardirqs last enabled at (440723): [] restore_all_notrace+0x0/0x18 [ 326.089755] hardirqs last disabled at (440724): [] debug_check_no_locks_freed+0x35/0x160 [ 326.089755] softirqs last enabled at (440722): [] __do_softirq+0x2b7/0x370 [ 326.089755] softirqs last disabled at (440715): [] do_softirq+0x64/0xd0 [ 327.331183] 4k 65533 large 0 gb 0 x 65533[c0000000-cfffc000] miss 0 [ 327.339297] ok. Thanks, Fengguang