RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1022471 - Met "Broke affinity for irq ..." in KVM guest kernel log with "virito driver + MSI"
Summary: Met "Broke affinity for irq ..." in KVM guest kernel log with "virito driver ...
Keywords:
Status: CLOSED NOTABUG
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: qemu-kvm
Version: 6.5
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: rc
: ---
Assignee: Virtualization Maintenance
QA Contact: Virtualization Bugs
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2013-10-23 11:05 UTC by Sibiao Luo
Modified: 2013-10-24 02:18 UTC (History)
11 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2013-10-23 13:24:47 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)

Description Sibiao Luo 2013-10-23 11:05:45 UTC 
Description of problem:
Met "Broke affinity for irq ..." in KVM guest kernel log with "virito driver + MSI".
(1).If disable the MSI via append 'pci=nomsi' in guest kernel line, there is no any "Broke affinity for irq xxx" message appear in guest kernel log.
(2).If use the 'IDE + e1000 + MSI', there also no "Broke affinity for irq xxx" message appear in guest kernel log.

Version-Release number of selected component (if applicable):
host info:
2.6.32-424.el6.x86_64
qemu-kvm-0.12.1.2-2.414.el6.x86_64
seabios-0.6.1.2-28.el6.x86_64
host info:
2.6.32-424.el6.x86_64

How reproducible:
100%

Steps to Reproduce:
1.boot guest with 'virtio-blk + virtio-nic + MSI'.
e.g:# /usr/libexec/qemu-kvm -M pc -S -cpu host -enable-kvm -m 2G -smp 2,sockets=2,cores=1,threads=1 -no-kvm-pit-reinjection -usb -device usb-tablet,id=input0 -name sluo -uuid 990ea161-6b67-47b2-b803-19fb01d30d30 -rtc base=localtime,clock=host,driftfix=slew -device virtio-serial-pci,id=virtio-serial0,max_ports=16,vectors=0,bus=pci.0,addr=0x3 -chardev socket,id=channel1,path=/tmp/helloworld1,server,nowait -device virtserialport,chardev=channel1,name=com.redhat.rhevm.vdsm,bus=virtio-serial0.0,id=port1 -chardev socket,id=channel2,path=/tmp/helloworld2,server,nowait -device virtserialport,chardev=channel2,name=com.redhat.rhevm.vdsm,bus=virtio-serial0.0,id=port2 -drive file=/home/RHEL-6.5-Snapshot-4-Server-x86_64.qcow2,if=none,id=drive-virtio-disk,format=qcow2,cache=none,aio=native,werror=stop,rerror=stop -device virtio-blk-pci,vectors=0,bus=pci.0,addr=0x4,scsi=off,drive=drive-virtio-disk,id=virtio-disk,bootindex=1 -netdev tap,id=hostnet0,vhost=on,script=/etc/qemu-ifup -device virtio-net-pci,netdev=hostnet0,id=virtio-net-pci0,mac=00:01:02:B6:40:21,bus=pci.0,addr=0x5 -device virtio-balloon-pci,id=ballooning,bus=pci.0,addr=0x6 -global PIIX4_PM.disable_s3=0 -global PIIX4_PM.disable_s4=0 -drive file=/home/my-data-disk.raw,if=none,id=drive-data-disk,format=raw,cache=none,werror=stop,rerror=stop -device virtio-blk-pci,bus=pci.0,addr=0x7,drive=drive-data-disk,id=data-disk -k en-us -boot menu=on -qmp tcp:0:4444,server,nowait -serial unix:/tmp/ttyS0,server,nowait -vnc :1 -spice disable-ticketing,port=5931 -monitor stdio

# cat /proc/interrupts
           CPU0       CPU1      
  0:        155          0   IO-APIC-edge      timer
  1:        111          0   IO-APIC-edge      i8042
  4:        173          0   IO-APIC-edge      serial
  7:          0          0   IO-APIC-edge      parport0
  8:          0          0   IO-APIC-edge      rtc0
  9:          0          0   IO-APIC-fasteoi   acpi
 10:          1          0   IO-APIC-fasteoi   virtio0
 11:       3581       3492   IO-APIC-fasteoi   uhci_hcd:usb1, virtio1, virtio3
 12:        104          0   IO-APIC-edge      i8042
 14:          0          0   IO-APIC-edge      ata_piix
 15:       1556          0   IO-APIC-edge      ata_piix
 24:          0          0   PCI-MSI-edge      virtio4-config
 25:        284          0   PCI-MSI-edge      virtio4-requests
 26:          0          0   PCI-MSI-edge      virtio2-config
 27:        264       7410   PCI-MSI-edge      virtio2-input
 28:          1          0   PCI-MSI-edge      virtio2-output
NMI:         10         11   Non-maskable interrupts
LOC:      23704      22719   Local timer interrupts
SPU:          0          0   Spurious interrupts
PMI:         10         11   Performance monitoring interrupts
IWI:          0          0   IRQ work interrupts
RES:       2886       3587   Rescheduling interrupts
CAL:         13        180   Function call interrupts
TLB:        447        638   TLB shootdowns
TRM:          0          0   Thermal event interrupts
THR:          0          0   Threshold APIC interrupts
MCE:          0          0   Machine check exceptions
MCP:          2          2   Machine check polls
ERR:          0
MIS:          0

# dmesg | grep irq
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)
nr_irqs_gsi: 24
NR_IRQS:33024 nr_irqs:424
pnp 00:01: [irq 8]
pnp 00:02: [irq 1]
pnp 00:03: [irq 12]
pnp 00:04: [irq 6]
pnp 00:05: [irq 7]
pnp 00:06: [irq 4]
ipmi_si: Trying default-specified kcs state machine at i/o address 0xca2, slave address 0x0, irq 0
ipmi_si: Trying default-specified smic state machine at i/o address 0xca9, slave address 0x0, irq 0
ipmi_si: Trying default-specified bt state machine at i/o address 0xe4, slave address 0x0, irq 0
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:06: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
uhci_hcd 0000:00:01.2: irq 11, io base 0x0000c020
PNP: PS/2 Controller [PNP0303:KBD,PNP0f13:MOU] at 0x60,0x64 irq 1,12
serio: i8042 KBD port at 0x60,0x64 irq 1
serio: i8042 AUX port at 0x60,0x64 irq 12
ata1: PATA max MWDMA2 cmd 0x1f0 ctl 0x3f6 bmdma 0xc000 irq 14
ata2: PATA max MWDMA2 cmd 0x170 ctl 0x376 bmdma 0xc008 irq 15
  alloc irq_desc for 24 on node -1
  alloc kstat_irqs on node -1
virtio-pci 0000:00:07.0: irq 24 for MSI/MSI-X
  alloc irq_desc for 25 on node -1
  alloc kstat_irqs on node -1
virtio-pci 0000:00:07.0: irq 25 for MSI/MSI-X
  alloc irq_desc for 26 on node -1
  alloc kstat_irqs on node -1
virtio-pci 0000:00:05.0: irq 26 for MSI/MSI-X
  alloc irq_desc for 27 on node -1
  alloc kstat_irqs on node -1
virtio-pci 0000:00:05.0: irq 27 for MSI/MSI-X
  alloc irq_desc for 28 on node -1
  alloc kstat_irqs on node -1
virtio-pci 0000:00:05.0: irq 28 for MSI/MSI-X
parport0: PC-style at 0x378, irq 7 [PCSPP,TRISTATE]
2.shotdown guest.
guest ]# poweroff

Actual results:
after step 2, there is "Broke affinity for irq ..." in KVM guest kernel log.
...
init: Re-executing /sbin/init
Halting system...
ACPI: Preparing to enter system sleep state S5
Disabling non-boot CPUs ...
Broke affinity for irq 9
Broke affinity for irq 11
Broke affinity for irq 27
SMP alternatives: switching to UP code
Power down.

Expected results:
there should no "Broke affinity for irq xxx" message appear in guest kernel log.

Additional info:
Comment 1 Sibiao Luo 2013-10-23 11:08:30 UTC 
The whole kernel log when shotdown guest.

# nc -U /tmp/ttyS0
Stopping certmonger: [  OK  ]
Stopping rhsmcertd...[  OK  ]
Stopping atd: [  OK  ]
Stopping cups: [  OK  ]
Stopping abrt daemon: [  OK  ]
Stopping sshd: [  OK  ]
Shutting down postfix: [  OK  ]
Stopping crond: [  OK  ]
Stopping automount: [  OK  ]
Stopping acpi daemon: [  OK  ]
Stopping HAL daemon: [  OK  ]
Stopping block device availability: Deactivating block devices:
  [SKIP]: unmount of vg_dhcp71101-lv_root (dm-0) mounted on /
[  OK  ]
Stopping NetworkManager daemon: [  OK  ]
Stopping system message bus: [  OK  ]
Stopping rpcbind: [  OK  ]
Stopping auditd: type=1305 audit(1382488877.995:13): audit_pid=0 old=1354 auid=4294967295 ses=4294967295 subj=system_u:system_r:auditd_t:s0 res=1
[  OK  ]
type=1305 audit(1382488878.101:14): audit_enabled=0 old=1 auid=4294967295 ses=4294967295 subj=system_u:system_r:auditctl_t:s0 res=1
Shutting down system logger: [  OK  ]
Shutting down interface eth0:  [  OK  ]
Shutting down loopback interface:  [  OK  ]
ip6tables: Setting chains to policy ACCEPT: filter [  OK  ]
ip6tables: Flushing firewall rules: [  OK  ]
ip6tables: Unloading modules: [  OK  ]
iptables: Setting chains to policy ACCEPT: filter [  OK  ]
iptables: Flushing firewall rules: [  OK  ]
iptables: Unloading modules: [  OK  ]
Stopping monitoring for VG vg_dhcp71101:   2 logical volume(s) in volume group "vg_dhcp71101" unmonitored
[  OK  ]
Sending all processes the TERM signal... [  OK  ]
Sending all processes the KILL signal... [  OK  ]
Saving random seed:  [  OK  ]
Syncing hardware clock to system time [  OK  ]
Turning off swap:  [  OK  ]
Turning off quotas:  [  OK  ]
Unmounting file systems:  [  OK  ]
init: Re-executing /sbin/init
Halting system...
ACPI: Preparing to enter system sleep state S5
Disabling non-boot CPUs ...
Broke affinity for irq 9
Broke affinity for irq 11
Broke affinity for irq 27
SMP alternatives: switching to UP code
Power down.
Comment 2 Alex Williamson 2013-10-23 13:24:47 UTC 
Why is this a bug?  The guest is shutting down and disabling non-boot CPUs.  If an IRQ is assigned to a CPU being disabled then affinity is broken.  This is not a bug, this is simply saying that the affinity configured (likely via irqbalanced) is now lost.  Re-open if I'm missing some reason for this to be triaged further.
Comment 3 Sibiao Luo 2013-10-24 02:18:30 UTC 
(In reply to Alex Williamson from comment #2)
> Why is this a bug?  The guest is shutting down and disabling non-boot CPUs. 
> If an IRQ is assigned to a CPU being disabled then affinity is broken.  This
> is not a bug, this is simply saying that the affinity configured (likely via
> irqbalanced) is now lost.  Re-open if I'm missing some reason for this to be
> triaged further.
OK, good catch, we will highlight in our MSI feature wiki page, thanks for your explains.
Note You need to log in before you can comment on or make changes to this bug.