Re: WARNING: at kernel/rcutree.c:1558 rcu_do_batch+0x386/0x3a0(),during CPU hotplug

From: Paul E. McKenney
Date: Wed Sep 12 2012 - 11:31:39 EST

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In reply to: Srivatsa S. Bhat: "WARNING: at kernel/rcutree.c:1558 rcu_do_batch+0x386/0x3a0(), duringCPU hotplug"
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On Wed, Sep 12, 2012 at 06:06:20PM +0530, Srivatsa S. Bhat wrote:
> On 07/19/2012 10:45 PM, Paul E. McKenney wrote:
> > On Thu, Jul 19, 2012 at 05:39:30PM +0530, Srivatsa S. Bhat wrote:
> >> Hi Paul,
> >>
> >> While running a CPU hotplug stress test on v3.5-rc7+
> >> (mainline commit 8a7298b7805ab) I hit this warning.
> >> I haven't tried to debug this yet...
> >>
> >> Line number 1550 maps to:
> >>
> >> WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));
> >>
> >> inside rcu_do_batch().
> >
> > Hello, Srivatsa,
> >
> > I believe that you need commit a16b7a69 (Prevent __call_rcu() from
> > invoking RCU core on offline CPUs), which is currently in -tip, queued
> > for 3.6. Please see below for the patch.
> >
> > Does this help?
> >
>
> Hi Paul,
>
> I am hitting the cpu_is_offline() warning in rcu_do_batch() (see 2 of the
> examples below) occasionally while testing CPU hotplug on Thomas' smp/hotplug
> branch in -tip. It does contain the commit that you had mentioned above.
>
> The stack trace suggests that we are not hitting this from the __call_rcu()
> path. So I guess this needs a different fix?

So there was an interrupt from stop_machine_stop(). Because RCU complained
about offline, I presume that this was on exit from stop_machine_stop().
(Otherwise, on entry to stop_machine_stop(), the CPU has not yet marked
itself offline, right?)

So my question is: Why didn't the CPU shut off all interrupts before
coming out of stop_machine_stop()?

Or am I confused about what is really happening here?

Thanx, Paul

> Regards,
> Srivatsa S. Bhat
>
> [ 53.882344] smpboot: CPU 7 is now offline
> [ 53.891072] CPU 12 MCA banks CMCI:6 CMCI:8
> [ 53.895621] CPU 15 MCA banks CMCI:2 CMCI:3 CMCI:5
> [ 53.914738] Broke affinity for irq 81
> [ 53.917769] do_IRQ: 8.211 No irq handler for vector (irq -1)
> [ 53.917769] ------------[ cut here ]------------
> [ 53.917769] WARNING: at kernel/rcutree.c:1558 rcu_do_batch+0x386/0x3a0()
> [ 53.917769] Hardware name: IBM System x -[7870C4Q]-
> [ 53.917769] Modules linked in: ipv6 cpufreq_conservative cpufreq_userspace cpufreq_powersave acpi_cpufreq mperf fuse loop dm_mod iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm cdc_ether usbnet ioatdma lpc_ich mfd_core crc32c_intel microcode mii pcspkr i2c_i801 shpchp i2c_core serio_raw bnx2 tpm_tis dca tpm pci_hotplug i7core_edac tpm_bios edac_core sg rtc_cmos button uhci_hcd ehci_hcd usbcore usb_common sd_mod crc_t10dif edd ext3 mbcache jbd fan processor mptsas mptscsih mptbase scsi_transport_sas scsi_mod thermal thermal_sys hwmon
> [ 53.917769] Pid: 47, comm: migration/8 Not tainted 3.6.0-rc1-tglx-hotplug-0.0.0.28.36b5ec9-default #1
> [ 53.917769] Call Trace:
> [ 53.917769] <IRQ> [<ffffffff810e7806>] ? rcu_do_batch+0x386/0x3a0
> [ 53.917769] [<ffffffff810e7806>] ? rcu_do_batch+0x386/0x3a0
> [ 53.917769] [<ffffffff8104338a>] warn_slowpath_common+0x7a/0xb0
> [ 53.917769] [<ffffffff810433d5>] warn_slowpath_null+0x15/0x20
> [ 53.917769] [<ffffffff810e7806>] rcu_do_batch+0x386/0x3a0
> [ 53.917769] [<ffffffff810ac8a0>] ? trace_hardirqs_on_caller+0x70/0x1b0
> [ 53.917769] [<ffffffff810ac9ed>] ? trace_hardirqs_on+0xd/0x10
> [ 53.917769] [<ffffffff810e9143>] __rcu_process_callbacks+0x1a3/0x200
> [ 53.917769] [<ffffffff810e9228>] rcu_process_callbacks+0x88/0x240
> [ 53.917769] [<ffffffff8104dc79>] __do_softirq+0x159/0x400
> [ 53.917769] [<ffffffff814c627c>] call_softirq+0x1c/0x30
> [ 53.917769] [<ffffffff810044f5>] do_softirq+0x95/0xd0
> [ 53.917769] [<ffffffff8104d745>] irq_exit+0xe5/0x100
> [ 53.917769] [<ffffffff81003c14>] do_IRQ+0x64/0xe0
> [ 53.917769] [<ffffffff814bc12f>] common_interrupt+0x6f/0x6f
> [ 53.917769] <EOI> [<ffffffff810cfe7a>] ? stop_machine_cpu_stop+0xda/0x130
> [ 53.917769] [<ffffffff810cfda0>] ? stop_one_cpu_nowait+0x50/0x50
> [ 53.917769] [<ffffffff810cfab9>] cpu_stopper_thread+0xd9/0x1b0
> [ 53.917769] [<ffffffff814bbe4f>] ? _raw_spin_unlock_irqrestore+0x3f/0x80
> [ 53.917769] [<ffffffff810cf9e0>] ? res_counter_init+0x50/0x50
> [ 53.917769] [<ffffffff810ac95d>] ? trace_hardirqs_on_caller+0x12d/0x1b0
> [ 53.917769] [<ffffffff810ac9ed>] ? trace_hardirqs_on+0xd/0x10
> [ 53.917769] [<ffffffff810cf9e0>] ? res_counter_init+0x50/0x50
> [ 53.917769] [<ffffffff8106deae>] kthread+0xde/0xf0
> [ 53.917769] [<ffffffff814c6184>] kernel_thread_helper+0x4/0x10
> [ 53.917769] [<ffffffff814bc1f0>] ? retint_restore_args+0x13/0x13
> [ 53.917769] [<ffffffff8106ddd0>] ? __init_kthread_worker+0x70/0x70
> [ 53.917769] [<ffffffff814c6180>] ? gs_change+0x13/0x13
> [ 53.917769] ---[ end trace f60a282810c4ce78 ]---
> [ 54.170634] smpboot: CPU 8 is now offline
> [ 54.192259] NOHZ: local_softirq_pending 200
> [ 54.197936] smpboot: CPU 9 is now offline
> [ 54.219707] NOHZ: local_softirq_pending 200
> [ 54.225795] smpboot: CPU 10 is now offline
>
>
> ---
>
> [ 372.482434] smpboot: CPU 11 is now offline
> [ 372.534211] smpboot: CPU 12 is now offline
> [ 372.539786] CPU 13 MCA banks CMCI:6 CMCI:8
> [ 372.582474] smpboot: CPU 13 is now offline
> [ 372.591006] CPU 14 MCA banks CMCI:6 CMCI:8
> [ 372.629745] ------------[ cut here ]------------
> [ 372.633736] WARNING: at kernel/rcutree.c:1558 rcu_do_batch+0x386/0x3a0()
> [ 372.633736] Hardware name: IBM System x -[7870C4Q]-
> [ 372.633736] Modules linked in: ipv6 cpufreq_conservative cpufreq_userspace cpufreq_powersave acpi_cpufreq mperf fuse loop dm_mod iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm crc32c_intel
> microcode serio_raw tpm_tis i7core_edac cdc_ether usbnet ioatdma mii lpc_ich pcspkr edac_core mfd_core bnx2 shpchp pci_hotplug i2c_i801 i2c_core dca tpm sg tpm_bios rtc_cmos button uhci_hcd ehci_hcd
> usbcore usb_common sd_mod crc_t10dif edd ext3 mbcache jbd fan processor mptsas mptscsih mptbase scsi_transport_sas scsi_mod thermal thermal_sys hwmon
> [ 372.633736] Pid: 8625, comm: migration/14 Not tainted 3.6.0-rc1-tglx-hotplug-0.0.0.28.36b5ec9-default #1
> [ 372.633736] Call Trace:
> [ 372.633736] <IRQ> [<ffffffff810e7806>] ? rcu_do_batch+0x386/0x3a0
> [ 372.633736] [<ffffffff810e7806>] ? rcu_do_batch+0x386/0x3a0
> [ 372.633736] [<ffffffff8104338a>] warn_slowpath_common+0x7a/0xb0
> [ 372.633736] [<ffffffff810433d5>] warn_slowpath_null+0x15/0x20
> [ 372.633736] [<ffffffff810e7806>] rcu_do_batch+0x386/0x3a0
> [ 372.633736] [<ffffffff810ac8a0>] ? trace_hardirqs_on_caller+0x70/0x1b0
> [ 372.633736] [<ffffffff810ac9ed>] ? trace_hardirqs_on+0xd/0x10
> [ 372.633736] [<ffffffff810e9143>] __rcu_process_callbacks+0x1a3/0x200
> [ 372.633736] [<ffffffff810e9228>] rcu_process_callbacks+0x88/0x240
> [ 372.633736] [<ffffffff8104dc79>] __do_softirq+0x159/0x400
> [ 372.633736] [<ffffffff814c627c>] call_softirq+0x1c/0x30
> [ 372.633736] [<ffffffff810044f5>] do_softirq+0x95/0xd0
> [ 372.633736] [<ffffffff8104d745>] irq_exit+0xe5/0x100
> [ 372.633736] [<ffffffff81028df9>] smp_apic_timer_interrupt+0x69/0xa0
> [ 372.633736] [<ffffffff814c5aef>] apic_timer_interrupt+0x6f/0x80
> [ 372.633736] <EOI> [<ffffffff810cfe7a>] ? stop_machine_cpu_stop+0xda/0x130
> [ 372.633736] [<ffffffff810cfda0>] ? stop_one_cpu_nowait+0x50/0x50
> [ 372.633736] [<ffffffff810cfab9>] cpu_stopper_thread+0xd9/0x1b0
> [ 372.633736] [<ffffffff814bbe4f>] ? _raw_spin_unlock_irqrestore+0x3f/0x80
> [ 372.633736] [<ffffffff810cf9e0>] ? res_counter_init+0x50/0x50
> [ 372.633736] [<ffffffff810ac95d>] ? trace_hardirqs_on_caller+0x12d/0x1b0
> [ 372.633736] [<ffffffff810ac9ed>] ? trace_hardirqs_on+0xd/0x10
> [ 372.633736] [<ffffffff810cf9e0>] ? res_counter_init+0x50/0x50
> [ 372.633736] [<ffffffff8106deae>] kthread+0xde/0xf0
> [ 372.633736] [<ffffffff814c6184>] kernel_thread_helper+0x4/0x10
> [ 372.633736] [<ffffffff814bc1f0>] ? retint_restore_args+0x13/0x13
> [ 372.633736] [<ffffffff8106ddd0>] ? __init_kthread_worker+0x70/0x70
> [ 372.633736] [<ffffffff814c6180>] ? gs_change+0x13/0x13
> [ 372.633736] ---[ end trace a4296a31284c846d ]---
> [ 372.883063] smpboot: CPU 14 is now offline
> [ 372.892721] CPU 15 MCA banks CMCI:6 CMCI:8
> [ 372.907250] smpboot: CPU 15 is now offline
> [ 372.911545] SMP alternatives: lockdep: fixing up alternatives
> [ 372.917292] SMP alternatives: switching to UP code
> [ 372.941917] SMP alternatives: lockdep: fixing up alternatives
>
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Next message: Michal Hocko: "Re: [PATCH 3/3] mm: Introduce HAVE_ARCH_TRANSPARENT_HUGEPAGE"
Previous message: Borislav Petkov: "Re: [PATCH] amd64_edac: Memory size reported double on processorfamily 0Fh"
In reply to: Srivatsa S. Bhat: "WARNING: at kernel/rcutree.c:1558 rcu_do_batch+0x386/0x3a0(), duringCPU hotplug"
Next in thread: Michael Wang: "Re: WARNING: at kernel/rcutree.c:1558 rcu_do_batch+0x386/0x3a0(),during CPU hotplug"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]