From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: perf events: cpu-clock with callchain generates WARNING Date: Fri, 18 Feb 2011 14:15:52 -0700 Message-ID: <4D5EE188.5090404@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pz0-f46.google.com ([209.85.210.46]:37151 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754435Ab1BRVP5 (ORCPT ); Fri, 18 Feb 2011 16:15:57 -0500 Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: LKML , linux-perf-users@vger.kernel.org perf-core branch as of commit 02ca752e4181e219e243cd61a60dd1da47251f11. Seems to be very reproducible with: perf record -v -e cpu-clock -c 100000 -ag -fo /tmp/perf.data [ 30.884016] WARNING: at /opt/kernel/perf-core/arch/x86/kernel/dumpstack_64.c:129 dump_trace+0x2bc/0x308() [ 30.884016] Hardware name: Bochs [ 30.884016] Perf: bad frame pointer = 0000000000001fff in callchain [ 30.884016] Modules linked in: sunrpc serio_raw virtio_net virtio_blk virtio_pci virtio_ring virtio [ 30.884016] Pid: 903, comm: perf Not tainted 2.6.38-rc5 #3 [ 30.884016] Call Trace: [ 30.884016] [] ? warn_slowpath_common+0x85/0x9d [ 30.884016] [] ? warn_slowpath_fmt+0x46/0x48 [ 30.884016] [] ? bad_to_user+0x70/0x5e0 [ 30.884016] [] ? dump_trace+0x2bc/0x308 [ 30.884016] [] ? kvm_clock_read+0x19/0x1b [ 30.884016] [] ? perf_callchain_kernel+0x5a/0x5c [ 30.884016] [] ? perf_prepare_sample+0xf2/0x1d2 [ 30.884016] [] ? __perf_event_overflow+0x140/0x18e [ 30.884016] [] ? sched_clock+0x9/0xd [ 30.884016] [] ? sched_clock_local+0x12/0x75 [ 30.884016] [] ? sched_clock_cpu+0xbb/0xc6 [ 30.884016] [] ? perf_event_overflow+0x14/0x16 [ 30.884016] [] ? perf_swevent_hrtimer+0x9e/0xeb [ 30.884016] [] ? system_call_after_swapgs+0x1a/0x6c [ 30.884016] [] ? __remove_hrtimer+0x62/0x6e [ 30.884016] [] ? __run_hrtimer+0xbc/0x142 [ 30.884016] [] ? perf_swevent_hrtimer+0x0/0xeb [ 30.884016] [] ? hrtimer_interrupt+0xd1/0x1bd [ 30.884016] [] ? smp_apic_timer_interrupt+0x79/0x8c [ 30.884016] [] ? apic_timer_interrupt+0x13/0x20 [ 30.884016] [] ? audit_syscall_exit+0x130/0x14c [ 30.884016] [] ? system_call_after_swapgs+0x1a/0x6c [ 30.884016] ---[ end trace 94efe95e8c0ba650 ]---