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Bug 667340 - kexec: Make sure to stop all CPUs before exiting the kernel
Summary: kexec: Make sure to stop all CPUs before exiting the kernel
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: kernel
Version: 6.0
Hardware: Unspecified
OS: Unspecified
low
medium
Target Milestone: rc
: ---
Assignee: Paolo Bonzini
QA Contact: Han Pingtian
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2011-01-05 10:15 UTC by Paolo Bonzini
Modified: 2011-08-30 07:26 UTC (History)
4 users (show)

Fixed In Version: kernel-2.6.32-117.el6
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2011-05-23 20:32:56 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2011:0542 0 normal SHIPPED_LIVE Important: Red Hat Enterprise Linux 6.1 kernel security, bug fix and enhancement update 2011-05-19 11:58:07 UTC

Description Paolo Bonzini 2011-01-05 10:15:11 UTC 
Before starting the new kernel kexec calls machine_shutdown to stop all
the cpus, which internally calls native_smp_send_stop. kexec
expects that all the cpus are now halted after that call returns.
However, native_smp_send_stop assumes that all the processors have
processed the REBOOT ipi in 1 second after the IPI was sent.

In the kexec case we can have the BSP starting the new kernel and AP's still
processing the REBOOT IPI simultaneously.

In virtualized environment with the host heavily overcommitted it is
possible to see VCPUs failing to process the IPI in the allotted 1 sec.
As a result the AP's end up accessing uninitialized state (the BSP has already
gone ahead with setting up the new state) and causing GPF's.

kexec expects machine_shutdown to return only after all cpus are stopped.
Patch 76fac077 waits for the cpus to stop in all cases except for panic/kdump
where we expect things to be broken and we are doing our best to make things work
anyway.

Patch 31e323cc is needed too, in order to avoid breaking Xen.

The two patches are respectively in upstream 2.6.32.26 and 2.6.32.27.
Comment 1 RHEL Program Management 2011-01-05 14:30:48 UTC 
This request was evaluated by Red Hat Product Management for inclusion
in a Red Hat Enterprise Linux maintenance release. Product Management has 
requested further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed 
products. This request is not yet committed for inclusion in an Update release.
Comment 3 Paolo Bonzini 2011-01-10 09:43:47 UTC 
You can try doing kexec in a RHEL6 guest (either Xen HVM on a RHEL5 host or KVM) while the host is under heavy load.

Separately, you can try rebooting a RHEL6 Xen PV guest on a RHEL5 host to ensure that there is no regression.
Comment 6 Han Pingtian 2011-01-12 03:11:55 UTC 
I have tried several times. I used usex to generate some load on the host, then load the new kernel with kexec -l then jump to the new kernel with reboot on the rhel6 kvm guest. I cannot cause the panic, only saw one time the guest didn't bypass the bois, it performed a normal boot. Is this a reproduction?
Comment 9 Paolo Bonzini 2011-01-13 09:57:08 UTC 
I think so, yes.  You can try the brew build at https://brewweb.devel.redhat.com/taskinfo?taskID=3022266 if you want to "pre-verify" now.
Comment 10 Han Pingtian 2011-01-14 08:26:56 UTC 
I have managed to let the testing kernel also doesn't bypass BIOS on kvm guest with a load average about 42~43 on the host, it can be achieved on my workstation using  'usex -e 34'.
Comment 21 Aristeu Rozanski 2011-02-18 22:14:41 UTC 
Patch(es) available on kernel-2.6.32-117.el6
Comment 25 Paolo Bonzini 2011-03-25 10:28:32 UTC 
Perhaps you can try the reproducer in bug 690419?  It's for a different bug, but it could work here too.
Comment 27 Paolo Bonzini 2011-03-28 07:18:12 UTC 
Start the CPU add-remove loop and a little after kexec.  After some time, without the patch you may see a failure to boot the new kernel.  With the patch, you will have to stop the loop for kexec to proceed.
Comment 28 Han Pingtian 2011-03-29 05:42:17 UTC 
I saw two times this kind of warnings with -71.el6 kvm x86_64 guest, on host tyan-gt24-01.rhts.eng.bos.redhat.com.

The first:
...
Unmounting file systems:  [  OK  ]
init: Re-executing /sbin/init
Please stand by while rebooting the system...
md: stopping all md devices.
Starting new kernel
------------[ cut here ]------------
WARNING: at arch/x86/kernel/smp.c:117 native_smp_send_reschedule+0x5c/0x60() (Not tainted)
Hardware name: KVM
Modules linked in: sit tunnel4 sunrpc ipv6 dm_mirror dm_region_hash dm_log virtio_balloon virtio_net i2c_piix4 i2c_core sg ext4 mbcache jbd2 virtio_blk sr_mod cdrom virtio_pci virtio_ring virtio pata_acpi ata_generic ata_piix dm_mod [last unloaded: freq_table]
Pid: 2190, comm: kexec Not tainted 2.6.32-71.el6.x86_64 #1
Call Trace:
 <IRQ>  [<ffffffff8106b857>] warn_slowpath_common+0x87/0xc0
 [<ffffffff8106b8aa>] warn_slowpath_null+0x1a/0x20
 [<ffffffff8102ea7c>] native_smp_send_reschedule+0x5c/0x60
 [<ffffffff810507f8>] resched_task+0x68/0x80
 [<ffffffff81057a6d>] resched_cpu+0x8d/0xa0
 [<ffffffff8106636b>] scheduler_tick+0x26b/0x280
 [<ffffffff810a0c90>] ? tick_sched_timer+0x0/0xc0
 [<ffffffff8107d7e2>] update_process_times+0x52/0x70
 [<ffffffff810a0cf6>] tick_sched_timer+0x66/0xc0
 [<ffffffff8109564e>] __run_hrtimer+0x8e/0x1a0
 [<ffffffff8103be39>] ? kvm_clock_get_cycles+0x9/0x10
 [<ffffffff810959f6>] hrtimer_interrupt+0xe6/0x250
 [<ffffffff814cf9fc>] smp_apic_timer_interrupt+0x6c/0x9c
 [<ffffffff81013c93>] apic_timer_interrupt+0x13/0x20
 <EOI>  [<ffffffff8101af06>] ? native_read_tsc+0x6/0x20
 [<ffffffff8126644c>] ? __bitmap_weight+0x8c/0xb0
 [<ffffffff8126333a>] delay_tsc+0x4a/0x80
 [<ffffffff812632e6>] __const_udelay+0x46/0x50
 [<ffffffff8102ebab>] native_smp_send_stop+0x6b/0xb0
 [<ffffffff8102e38f>] native_machine_shutdown+0x5f/0x80
 [<ffffffff8103bd75>] kvm_shutdown+0x15/0x20
 [<ffffffff8102df5f>] machine_shutdown+0xf/0x20
 [<ffffffff810b8928>] kernel_kexec+0x158/0x160
 [<ffffffff8108a5a4>] sys_reboot+0x144/0x220
 [<ffffffff8105c394>] ? try_to_wake_up+0x284/0x380
 [<ffffffff8106789a>] ? __cond_resched+0x2a/0x40
 [<ffffffff810d40a2>] ? audit_syscall_entry+0x272/0x2a0
 [<ffffffff81013172>] system_call_fastpath+0x16/0x1b
---[ end trace 0f4c73c2233b3107 ]---

Second:
...
Starting new kernel
------------[ cut here ]------------
WARNING: at arch/x86/kernel/smp.c:117 native_smp_send_reschedule+0x5c/0x60() (Not tainted)
Hardware name: KVM
Modules linked in: sit tunnel4 sunrpc ipv6 dm_mirror dm_region_hash dm_log virtio_balloon virtio_net i2c_piix4 i2c_core sg ext4 mbcache jbd2 virtio_blk sr_mod cdrom virtio_pci virtio_ring virtio pata_acpi ata_generic ata_piix dm_mod [last unloaded: freq_table]
Pid: 22142, comm: kexec Not tainted 2.6.32-71.el6.x86_64 #1
Call Trace:
 <IRQ>  [<ffffffff8106b857>] warn_slowpath_common+0x87/0xc0
 [<ffffffff8106b8aa>] warn_slowpath_null+0x1a/0x20
 [<ffffffff8102ea7c>] native_smp_send_reschedule+0x5c/0x60
 [<ffffffff810507f8>] resched_task+0x68/0x80
 [<ffffffff81057a6d>] resched_cpu+0x8d/0xa0
 [<ffffffff8106636b>] scheduler_tick+0x26b/0x280
 [<ffffffff810a0c90>] ? tick_sched_timer+0x0/0xc0
 [<ffffffff8107d7e2>] update_process_times+0x52/0x70
 [<ffffffff810a0cf6>] tick_sched_timer+0x66/0xc0
 [<ffffffff8109564e>] __run_hrtimer+0x8e/0x1a0
 [<ffffffff8103be39>] ? kvm_clock_get_cycles+0x9/0x10
 [<ffffffff810959f6>] hrtimer_interrupt+0xe6/0x250
 [<ffffffff814cf9fc>] smp_apic_timer_interrupt+0x6c/0x9c
 [<ffffffff81013c93>] apic_timer_interrupt+0x13/0x20
 <EOI>  [<ffffffff81034721>] ? native_apic_mem_write+0x11/0x20
 [<ffffffff8102f9ad>] disconnect_bsp_APIC+0x3d/0xc0
 [<ffffffff810329b2>] disable_IO_APIC+0xa2/0x110
 [<ffffffff8102f906>] ? disable_local_APIC+0x46/0x50
 [<ffffffff8102e399>] native_machine_shutdown+0x69/0x80
 [<ffffffff8103bd75>] kvm_shutdown+0x15/0x20
 [<ffffffff8102df5f>] machine_shutdown+0xf/0x20
 [<ffffffff810b8928>] kernel_kexec+0x158/0x160
 [<ffffffff8108a5a4>] sys_reboot+0x144/0x220
 [<ffffffff810507f8>] ? resched_task+0x68/0x80
 [<ffffffff8105c394>] ? try_to_wake_up+0x284/0x380
 [<ffffffff8105c4e5>] ? wake_up_process+0x15/0x20
 [<ffffffff8119522d>] ? bdi_queue_work+0x7d/0x110
 [<ffffffff810d40a2>] ? audit_syscall_entry+0x272/0x2a0
 [<ffffffff81013172>] system_call_fastpath+0x16/0x1b
---[ end trace c3b8a463f323d0c9 ]---
Initializing cgroup subsys cpuset
Initializing cgroup subsys cpu
Linux version 2.6.32-71.el6.x86_64 (mockbuild.bos.redhat.com) (gcc version 4.4.4 20100726 (Red Hat 4.4.4-13) (GCC) ) #1 SMP Wed Sep 1 01:33:01 EDT 2010
Command line: ro root=/dev/mapper/vg_dhcp71107-lv_root rd_LVM_LV=vg_dhcp71107/lv_root rd_LVM_LV=vg_dhcp71107/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us console=ttyS0,115200
KERNEL supported cpus:
  Intel GenuineIntel
  AMD AuthenticAMD
  Centaur CentaurHauls
BIOS-provided physical RAM map:
 BIOS-e820: 0000000000000100 - 000000000009cc00 (usable)
 BIOS-e820: 000000000009cc00 - 00000000000a0000 (reserved)
 BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
 BIOS-e820: 0000000000100000 - 000000001fffb000 (usable)
 BIOS-e820: 000000001fffb000 - 0000000020000000 (reserved)
 BIOS-e820: 00000000fffbc000 - 0000000100000000 (reserved)
DMI 2.4 present.
last_pfn = 0x1fffb max_arch_pfn = 0x400000000
x86 PAT enabled: cpu 0, old 0x70106, new 0x7010600070106
init_memory_mapping: 0000000000000000-000000001fffb000
RAMDISK: 1f31f000 - 1ffefd30
ACPI: RSDP 00000000000f80a0 00014 (v00 BOCHS )
ACPI: RSDT 000000001fffdda0 00030 (v01 BOCHS  BXPCRSDT 00000001 BXPC 00000001)
ACPI: FACP 000000001ffffdc0 00074 (v01 BOCHS  BXPCFACP 00000001 BXPC 00000001)
ACPI: DSDT 000000001fffdf30 01E4B (v01   BXPC   BXDSDT 00000001 INTL 20090123)
ACPI: FACS 000000001ffffd80 00040
ACPI: SSDT 000000001fffded0 0005E (v01 BOCHS  BXPCSSDT 00000001 BXPC 00000001)
ACPI: APIC 000000001fffddd0 0008A (v01 BOCHS  BXPCAPIC 00000001 BXPC 00000001)
No NUMA configuration found
Faking a node at 0000000000000000-000000001fffb000
Bootmem setup node 0 0000000000000000-000000001fffb000
  NODE_DATA [0000000000009000 - 000000000003cfff]
  bootmap [000000000003d000 -  0000000000040fff] pages 4
(7 early reservations) ==> bootmem [0000000000 - 001fffb000]
  #0 [0000000000 - 0000001000]   BIOS data page ==> [0000000000 - 0000001000]
  #1 [0000006000 - 0000008000]       TRAMPOLINE ==> [0000006000 - 0000008000]
  #2 [0001000000 - 0001c9eff8]    TEXT DATA BSS ==> [0001000000 - 0001c9eff8]
  #3 [001f31f000 - 001ffefd30]          RAMDISK ==> [001f31f000 - 001ffefd30]
  #4 [000009cc00 - 0000100000]    BIOS reserved ==> [000009cc00 - 0000100000]
  #5 [0001c9f000 - 0001c9f079]              BRK ==> [0001c9f000 - 0001c9f079]
  #6 [0000008000 - 0000009000]          PGTABLE ==> [0000008000 - 0000009000]
found SMP MP-table at [ffff8800000f80f0] f80f0
kvm-clock: Using msrs 12 and 11
kvm-clock: cpu 0, msr 0:18bf901, boot clock
Zone PFN ranges:
  DMA      0x00000001 -> 0x00001000
  DMA32    0x00001000 -> 0x00100000
  Normal   0x00100000 -> 0x00100000
Movable zone start PFN for each node
early_node_map[2] active PFN ranges
    0: 0x00000001 -> 0x0000009c
    0: 0x00000100 -> 0x0001fffb
ACPI: PM-Timer IO Port: 0xb008
ACPI: LAPIC (acpi_id[0x00] lapic_id[0x00] enabled)
ACPI: LAPIC (acpi_id[0x01] lapic_id[0x01] enabled)
ACPI: LAPIC (acpi_id[0x02] lapic_id[0x02] enabled)
ACPI: LAPIC (acpi_id[0x03] lapic_id[0x03] enabled)
ACPI: IOAPIC (id[0x04] address[0xfec00000] gsi_base[0])
IOAPIC[0]: apic_id 4, version 17, address 0xfec00000, GSI 0-23
ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level)
ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level)
ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level)
Using ACPI (MADT) for SMP configuration information
SMP: Allowing 4 CPUs, 0 hotplug CPUs
PM: Registered nosave memory: 000000000009c000 - 000000000009d000
PM: Registered nosave memory: 000000000009d000 - 00000000000a0000
PM: Registered nosave memory: 00000000000a0000 - 00000000000f0000
PM: Registered nosave memory: 00000000000f0000 - 0000000000100000
Allocating PCI resources starting at 20000000 (gap: 20000000:dffbc000)
Booting paravirtualized kernel on KVM
NR_CPUS:4096 nr_cpumask_bits:4 nr_cpu_ids:4 nr_node_ids:1
PERCPU: Embedded 31 pages/cpu @ffff880001e00000 s95064 r8192 d23720 u524288
pcpu-alloc: s95064 r8192 d23720 u524288 alloc=1*2097152
pcpu-alloc: [0] 0 1 2 3
kvm-clock: cpu 0, msr 0:1e16901, primary cpu clock
Built 1 zonelists in Node order, mobility grouping on.  Total pages: 129071
Policy zone: DMA32
Kernel command line: ro root=/dev/mapper/vg_dhcp71107-lv_root rd_LVM_LV=vg_dhcp71107/lv_root rd_LVM_LV=vg_dhcp71107/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us console=ttyS0,115200
PID hash table entries: 2048 (order: 2, 16384 bytes)
Checking aperture...
No AGP bridge found
AMD-Vi disabled by default: pass amd_iommu=on to enable
Memory: 488640k/524268k available (4935k kernel code, 404k absent, 35224k reserved, 3927k data, 1220k init)
Hierarchical RCU implementation.
NR_IRQS:33024 nr_irqs:440
Console: colour VGA+ 80x25
console [ttyS0] enabled
allocated 5242880 bytes of page_cgroup
please try 'cgroup_disable=memory' option if you don't want memory cgroups
Detected 2394.012 MHz processor.
Calibrating delay loop (skipped) preset value.. 4788.02 BogoMIPS (lpj=2394012)
pid_max: default: 32768 minimum: 301
Security Framework initialized
SELinux:  Initializing.
Dentry cache hash table entries: 65536 (order: 7, 524288 bytes)
Inode-cache hash table entries: 32768 (order: 6, 262144 bytes)
Mount-cache hash table entries: 256
Initializing cgroup subsys ns
Initializing cgroup subsys cpuacct
Initializing cgroup subsys memory
Initializing cgroup subsys devices
Initializing cgroup subsys freezer
Initializing cgroup subsys net_cls
Initializing cgroup subsys blkio
mce: CPU supports 10 MCE banks
Performance Events: AMD PMU driver.
... version:                0
... bit width:              48
... generic registers:      4
... value mask:             0000ffffffffffff
... max period:             00007fffffffffff
... fixed-purpose events:   0
... event mask:             000000000000000f
alternatives: switching to unfair spinlock
ACPI: Core revision 20090903
ftrace: converting mcount calls to 0f 1f 44 00 00
ftrace: allocating 20276 entries in 80 pages
Setting APIC routing to flat
..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
CPU0: AMD QEMU Virtual CPU version (cpu64-rhel6) stepping 03
Booting Node   0, Processors  #1
kvm-clock: cpu 1, msr 0:1e96901, secondary cpu clock
 #2
kvm-clock: cpu 2, msr 0:1f16901, secondary cpu clock
 #3 Ok.
kvm-clock: cpu 3, msr 0:1f96901, secondary cpu clock
Brought up 4 CPUs
Total of 4 processors activated (19152.09 BogoMIPS).
Testing NMI watchdog ...
WARNING: CPU#0: NMI appears to be stuck (0->0)!
Please report this to bugzilla.kernel.org,
and attach the output of the 'dmesg' command.

WARNING: CPU#1: NMI appears to be stuck (0->0)!
Please report this to bugzilla.kernel.org,
and attach the output of the 'dmesg' command.

WARNING: CPU#2: NMI appears to be stuck (0->0)!
Please report this to bugzilla.kernel.org,
and attach the output of the 'dmesg' command.

WARNING: CPU#3: NMI appears to be stuck (0->0)!
Please report this to bugzilla.kernel.org,
and attach the output of the 'dmesg' command.
devtmpfs: initialized
regulator: core version 0.5
NET: Registered protocol family 16
ACPI: bus type pci registered
PCI: Using configuration type 1 for base access
bio: create slab <bio-0> at 0
ACPI: Interpreter enabled
ACPI: (supports S0 S3 S4 S5)
ACPI: Using IOAPIC for interrupt routing
ACPI: No dock devices found.
ACPI: PCI Root Bridge [PCI0] (0000:00)
pci 0000:00:01.3: quirk: region b000-b03f claimed by PIIX4 ACPI
pci 0000:00:01.3: quirk: region b100-b10f claimed by PIIX4 SMB
Unable to assume PCIe control: Disabling ASPM
ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11)
ACPI: PCI Interrupt Link [LNKB] (IRQs 5 10 11) *0, disabled.
ACPI: PCI Interrupt Link [LNKC] (IRQs 5 *10 11)
ACPI: PCI Interrupt Link [LNKD] (IRQs 5 10 *11)
vgaarb: device added: PCI:0000:00:02.0,decodes=io+mem,owns=io+mem,locks=none
vgaarb: loaded
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
PCI: Using ACPI for IRQ routing
NetLabel: Initializing
NetLabel:  domain hash size = 128
NetLabel:  protocols = UNLABELED CIPSOv4
NetLabel:  unlabeled traffic allowed by default
Switching to clocksource kvm-clock
pnp: PnP ACPI init
ACPI: bus type pnp registered
pnp: PnP ACPI: found 6 devices
ACPI: ACPI bus type pnp unregistered
NET: Registered protocol family 2
IP route cache hash table entries: 4096 (order: 3, 32768 bytes)
TCP established hash table entries: 16384 (order: 6, 262144 bytes)
TCP bind hash table entries: 16384 (order: 6, 262144 bytes)
TCP: Hash tables configured (established 16384 bind 16384)
TCP reno registered
NET: Registered protocol family 1
pci 0000:00:00.0: Limiting direct PCI/PCI transfers
pci 0000:00:01.0: Activating ISA DMA hang workarounds
Trying to unpack rootfs image as initramfs...
rootfs image is not initramfs (broken padding); looks like an initrd
Freeing initrd memory: 13123k freed
audit: initializing netlink socket (disabled)
type=2000 audit(1301369751.257:1): initialized
HugeTLB registered 2 MB page size, pre-allocated 0 pages
VFS: Disk quotas dquot_6.5.2
Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
msgmni has been set to 980
alg: No test for stdrng (krng)
ksign: Installing public key data
Loading keyring
- Added public key 9D480283FFC05098
- User ID: Red Hat, Inc. (Kernel Module GPG key)
- Added public key D4A26C9CCD09BEDA
- User ID: Red Hat Enterprise Linux Driver Update Program <secalert>
Block layer SCSI generic (bsg) driver version 0.4 loaded (major 252)
io scheduler noop registered
io scheduler anticipatory registered
io scheduler deadline registered
io scheduler cfq registered (default)
pci_hotplug: PCI Hot Plug PCI Core version: 0.5
pciehp: PCI Express Hot Plug Controller Driver version: 0.4
acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
acpiphp: Slot [1] registered
acpiphp: Slot [2] registered
acpiphp: Slot [3] registered
acpiphp: Slot [4] registered
acpiphp: Slot [5] registered
acpiphp: Slot [6] registered
acpiphp: Slot [7] registered
acpiphp: Slot [8] registered
acpiphp: Slot [9] registered
acpiphp: Slot [10] registered
acpiphp: Slot [11] registered
acpiphp: Slot [12] registered
acpiphp: Slot [13] registered
acpiphp: Slot [14] registered
acpiphp: Slot [15] registered
acpiphp: Slot [16] registered
acpiphp: Slot [17] registered
acpiphp: Slot [18] registered
acpiphp: Slot [19] registered
acpiphp: Slot [20] registered
acpiphp: Slot [21] registered
acpiphp: Slot [22] registered
acpiphp: Slot [23] registered
acpiphp: Slot [24] registered
acpiphp: Slot [25] registered
acpiphp: Slot [26] registered
acpiphp: Slot [27] registered
acpiphp: Slot [28] registered
acpiphp: Slot [29] registered
acpiphp: Slot [30] registered
acpiphp: Slot [31] registered
pci-stub: invalid id string ""
input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0
ACPI: Power Button [PWRF]
processor LNXCPU:00: registered as cooling_device0
processor LNXCPU:01: registered as cooling_device1
processor LNXCPU:02: registered as cooling_device2
processor LNXCPU:03: registered as cooling_device3
hpet_acpi_add: no address or irqs in _CRS
Non-volatile memory driver v1.3
Linux agpgart interface v0.103
crash memory driver: version 1.0
Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
Comment 29 Han Pingtian 2011-03-29 06:44:10 UTC 
On the other hand, I cannot reproduce this warning with -127.el6 x86_64 kvm guest. Is this enough to verify this bug?
Comment 30 Paolo Bonzini 2011-03-29 08:18:55 UTC 
I think so, yes.
Comment 31 Han Pingtian 2011-03-29 10:07:13 UTC 
Due to comment 28-30, setting it verified. Thanks!
Comment 32 errata-xmlrpc 2011-05-23 20:32:56 UTC 
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2011-0542.html
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