linux/arch/x86
Feng Tang 55c844a4dd x86/reboot: Fix a warning message triggered by stop_other_cpus()
When rebooting our 24 CPU Westmere servers with 3.4-rc6, we
always see this warning msg:

Restarting system.
machine restart
------------[ cut here ]------------
WARNING: at arch/x86/kernel/smp.c:125
native_smp_send_reschedule+0x74/0xa7() Hardware name: X8DTN
Modules linked in: igb [last unloaded: scsi_wait_scan]
Pid: 1, comm: systemd-shutdow Not tainted 3.4.0-rc6+ #22
Call Trace:
 <IRQ>  [<ffffffff8102a41f>] warn_slowpath_common+0x7e/0x96
 [<ffffffff8102a44c>] warn_slowpath_null+0x15/0x17
 [<ffffffff81018cf7>] native_smp_send_reschedule+0x74/0xa7
 [<ffffffff810561c1>] trigger_load_balance+0x279/0x2a6
 [<ffffffff81050112>] scheduler_tick+0xe0/0xe9
 [<ffffffff81036768>] update_process_times+0x60/0x70
 [<ffffffff81062f2f>] tick_sched_timer+0x68/0x92
 [<ffffffff81046e33>] __run_hrtimer+0xb3/0x13c
 [<ffffffff81062ec7>] ? tick_nohz_handler+0xd0/0xd0
 [<ffffffff810474f2>] hrtimer_interrupt+0xdb/0x198
 [<ffffffff81019a35>] smp_apic_timer_interrupt+0x81/0x94
 [<ffffffff81655187>] apic_timer_interrupt+0x67/0x70
 <EOI>  [<ffffffff8101a3c4>] ? default_send_IPI_mask_allbutself_phys+0xb4/0xc4
 [<ffffffff8101c680>] physflat_send_IPI_allbutself+0x12/0x14
 [<ffffffff81018db4>] native_nmi_stop_other_cpus+0x8a/0xd6
 [<ffffffff810188ba>] native_machine_shutdown+0x50/0x67
 [<ffffffff81018926>] machine_shutdown+0xa/0xc
 [<ffffffff8101897e>] native_machine_restart+0x20/0x32
 [<ffffffff810189b0>] machine_restart+0xa/0xc
 [<ffffffff8103b196>] kernel_restart+0x47/0x4c
 [<ffffffff8103b2e6>] sys_reboot+0x13e/0x17c
 [<ffffffff8164e436>] ? _raw_spin_unlock_bh+0x10/0x12
 [<ffffffff810fcac9>] ? bdi_queue_work+0xcf/0xd8
 [<ffffffff810fe82f>] ? __bdi_start_writeback+0xae/0xb7
 [<ffffffff810e0d64>] ? iterate_supers+0xa3/0xb7
 [<ffffffff816547a2>] system_call_fastpath+0x16/0x1b
---[ end trace 320af5cb1cb60c5b ]---

The root cause seems to be the
default_send_IPI_mask_allbutself_phys() takes quite some time (I
measured it could be several ms) to complete sending NMIs to all
the other 23 CPUs, and for HZ=250/1000 system, the time is long
enough for a timer interrupt to happen, which will in turn
trigger to kick load balance to a stopped CPU and cause this
warning in native_smp_send_reschedule().

So disabling the local irq before stop_other_cpu() can fix this
problem (tested 25 times reboot ok), and it is fine as there
should be nobody caring the timer interrupt in such reboot
stage.

The latest 3.4 kernel slightly changes this behavior by sending
REBOOT_VECTOR first and only send NMI_VECTOR if the REBOOT_VCTOR
fails, and this patch is still needed to prevent the problem.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120530231541.4c13433a@feng-i7
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06 12:03:23 +02:00
..
boot x86, efi; Add EFI boot stub console support 2012-06-01 09:11:26 -07:00
configs x86/kconfig: Remove CONFIG_TR=y from the defconfigs 2012-03-24 08:18:03 +01:00
crypto crypto: aesni-intel - move more common code to ablk_init_common 2012-05-15 17:25:33 +10:00
ia32 most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set 2012-06-01 12:58:51 -04:00
include/asm Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-06-02 16:17:03 -07:00
kernel x86/reboot: Fix a warning message triggered by stop_other_cpus() 2012-06-06 12:03:23 +02:00
kvm KVM: MMU: fix huge page adapted on non-PAE host 2012-05-28 17:41:15 +03:00
lguest lguest: Make sure interrupt is allocated ok by lguest_setup_irq 2012-01-12 15:44:47 +10:30
lib x86: use the new generic strnlen_user() function 2012-05-26 11:33:54 -07:00
math-emu x86: Rename trap_no to trap_nr in thread_struct 2012-03-13 06:24:09 +01:00
mm x86/numa: Set numa_nodes_parsed at acpi_numa_memory_affinity_init() 2012-06-06 11:58:39 +02:00
net bpf jit: Let the x86 jit handle negative offsets 2012-04-03 18:01:41 -04:00
oprofile x86: Factor out TIF_IA32 from 32-bit address space 2012-02-20 12:48:46 -08:00
pci Features: 2012-05-24 16:02:08 -07:00
platform x86/intel/moorestown: Change intel_scu_devices_create() to __devinit 2012-06-06 11:58:40 +02:00
power x86, kvm: Call restore_sched_clock_state() only after %gs is initialized 2012-04-02 13:53:00 +02:00
realmode x86, realmode: Move end signature into header.S 2012-05-21 00:02:45 -07:00
syscalls syscalls, x86: add __NR_kcmp syscall 2012-05-31 17:49:32 -07:00
tools Merge branch 'x86-trampoline-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-05-29 20:14:53 -07:00
um most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set 2012-06-01 12:58:51 -04:00
vdso Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:12:23 -07:00
video x86: Use vga_default_device() when determining whether an fb is primary 2012-04-24 09:50:17 +01:00
xen x86, amd, xen: Avoid NULL pointer paravirt references 2012-05-30 16:15:02 -07:00
.gitignore x86/kprobes: Add arch/x86/tools/insn_sanity to .gitignore 2012-01-16 08:21:59 +01:00
Kbuild x86, realmode: realmode.bin infrastructure 2012-05-08 11:41:48 -07:00
Kconfig x86, efi: Add EFI boot stub documentation 2012-06-01 09:11:41 -07:00
Kconfig.cpu x86: Tighten dependencies of CPU_SUP_*_32 2012-03-08 10:57:34 +01:00
Kconfig.debug Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-01-11 19:13:40 -08:00
Makefile md updates for 3.5 2012-05-23 17:08:40 -07:00
Makefile_32.cpu
Makefile.um um: fix linker script generation 2012-04-09 13:59:00 -04:00