Bug 570824

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.

*** Bug 599034 has been marked as a duplicate of this bug. ***

in kernel-2.6.18-203.el5
You can download this test kernel from http://people.redhat.com/jwilson/el5

Detailed testing feedback is always welcomed.

*** Bug 588997 has been marked as a duplicate of this bug. ***

*** Bug 584310 has been marked as a duplicate of this bug. ***

Technical note added. If any revisions are required, please edit the "Technical Notes" field
accordingly. All revisions will be proofread by the Engineering Content Services team.

New Contents:
Red Hat Enterprise Linux 5.4 SMP guests running on the Red Hat Enterprise Virtualization Hypervisor may have experienced inconsistent time, such as the clock driftingbackwards. This could have caused some applications to become unresponsive.

Can I add that this fix description doesn't match what I experienced at all: the *kernel* hogged 100% cpu and the guest was as good as unusable: no attempts to connect by any method, console or otherwise, worked.

Glauber,

Could you please check the Technical Note for this bug to ensure it matches the conditions and fix?

Thank you,

Silas

Technical note updated. If any revisions are required, please edit the "Technical Notes" field
accordingly. All revisions will be proofread by the Engineering Content Services team.

Diffed Contents:
@@ -1 +1 @@
-Red Hat Enterprise Linux 5.4 SMP guests running on the Red Hat Enterprise Virtualization Hypervisor may have experienced inconsistent time, such as the clock driftingbackwards. This could have caused some applications to become unresponsive.+Red Hat Enterprise Linux 5.4 SMP guests running on the Red Hat Enterprise Virtualization Hypervisor may have experienced inconsistent time, such as the clock drifting backwards. This could have caused some applications to become unresponsive.

comment #16: Sure, but unfortunately, problems that are generated by time drifts are unpredictable at best.

comment #18: driftingbackwards => drifting backwards, otherwise, ok.

Fixed "driftingbackwards" earlier in the Tech Notes field. Thanks for the response; leaving note as-is.

*** Bug 587150 has been marked as a duplicate of this bug. ***

*** Bug 523471 has been marked as a duplicate of this bug. ***

*** Bug 619311 has been marked as a duplicate of this bug. ***

Running gettimeofday for 32hours .No find timedrift.

Host kernel:
#uname -r
2.6.18-230.el5
Guest Kernel:
2.6.18-231.el5


Result
=============+=======+=====
64bitrhel5.6 | amd | pass
64bitrhel5.6 | Intel | pass
32bitrhel5.6 | amd | pass
32bitrhel5.6 | Intel | pass 
===========================

CLI
/usr/libexec/qemu-kvm -drive file=/root/RHEL-server-5.6-32.raw,if=virtio,boot=on,format=raw -no-hpet -rtc-td-hack -usbdevice tablet -startdate now -smp 2 -m 2G -net nic,model=virtio,macaddr=20:20:20:11:23:5f,vlan=0 -net tap,vlan=0,script=/etc/qemu-ifup -cpu qemu64,+sse2 -name 64 -monitor stdio -vnc :10 -no-kvm-pit-reinjection

/usr/libexec/qemu-kvm -drive file=/root/RHEL-Server-5.6-64.qcow2,if=virtio,boot=on -no-hpet -rtc-td-hack -usbdevice tablet -startdate now -smp 2 -m 2G -net nic,model=virtio,macaddr=20:20:20:11:23:51,vlan=0 -net tap,vlan=0,script=/etc/qemu-ifup -cpu qemu64,+sse2 -name 64 -monitor stdio -vnc :9 -no-kvm-pit-reinjection

/usr/libexec/qemu-kvm -drive file=/root/RHEL-server-5.6-32.raw,if=virtio,boot=on,format=raw -no-hpet -rtc-td-hack -usbdevice tablet -startdate now -smp 2 -m 2G -net nic,model=virtio,macaddr=20:20:20:11:23:5f,vlan=0 -net tap,vlan=0,script=/etc/qemu-ifup -cpu qemu64,+sse2 -name 64 -monitor stdio -vnc :10 -no-kvm-pit-reinjection

/usr/libexec/qemu-kvm -drive file=/root/RHEL-Server-5.6-64.qcow2,if=virtio,boot=on -no-hpet -rtc-td-hack -usbdevice tablet -startdate now -smp 2 -m 2G -net nic,model=virtio,macaddr=20:20:20:11:23:51,vlan=0 -net tap,vlan=0,script=/etc/qemu-ifup -cpu qemu64,+sse2 -name 64 -monitor stdio -vnc :9 -no-kvm-pit-reinjection

Steps:
1.Boot a rhel5.6 guest
2.Run #./gettimeofday  inside guest
3.All guests current clock source is kvm-clock

AMD HOST
 cat /proc/cpuinfo 
processor	: 0
vendor_id	: AuthenticAMD
cpu family	: 16
model		: 2
model name	: AMD Phenom(tm) 9600B Quad-Core Processor
stepping	: 3
cpu MHz		: 1200.000
cache size	: 512 KB
physical id	: 0
siblings	: 4
core id		: 0
cpu cores	: 4
apicid		: 0
fpu		: yes
fpu_exception	: yes
cpuid level	: 5
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc nonstop_tsc pni cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy altmovcr8 abm sse4a misalignsse 3dnowprefetch osvw
bogomips	: 4587.49
TLB size	: 1024 4K pages
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate [8]

Intel HOST
#cat /proc/cpuinfo 
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 26
model name	: Intel(R) Xeon(R) CPU           X5550  @ 2.67GHz
stepping	: 5
cpu MHz		: 1596.000
cache size	: 8192 KB
physical id	: 0
siblings	: 8
core id		: 0
cpu cores	: 4
apicid		: 0
fpu		: yes
fpu_exception	: yes
cpuid level	: 11
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx rdtscp lm constant_tsc ida nonstop_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm
bogomips	: 5333.67
clflush size	: 64
cache_alignment	: 64
address sizes	: 40 bits physical, 48 bits virtual

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-2011-0017.html