Bug 690134 – Time runs too fast in a VM on processors with > 4GHZ freq [rhel-5.6.z]

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Bug 690134 - Time runs too fast in a VM on processors with > 4GHZ freq [rhel-5.6.z]

Summary:	Time runs too fast in a VM on processors with > 4GHZ freq [rhel-5.6.z]

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 5
Classification:	Red Hat
Component:	kernel (Show other bugs)
Sub Component:
Version:	5.7
Hardware:	All Linux

Priority	urgent Severity high
Target Milestone:	rc
Target Release:	---
Assigned To:	Zachary Amsden
QA Contact:	Red Hat Kernel QE team
Docs Contact:

URL:
Whiteboard:
Keywords:	ZStream

Depends On:	673242
Blocks:
	Show dependency tree / graph

Reported:	2011-03-23 08:14 EDT by RHEL Product and Program Management
Modified:	2013-01-10 22:53 EST (History)
CC List:	17 users (show)

See Also:
Fixed In Version:	kernel-2.6.18-238.10.1.el5
Doc Type:	Bug Fix
Doc Text:	Previously, on VMware, the time ran too fast on virtual machines with more than 4GHz TSC (Time Step Counter) processor frequency if they were using PIT/TSC based timekeeping. This was due to a calculation bug in the get_hypervisor_cycles_per_sec function. This update fixes the calculation, and timekeeping works correctly for such virtual machines
Story Points:	---
Clone Of:
Environment:
Last Closed:	2011-05-31 10:08:52 EDT
Type:	---
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

Attachments	(Terms of Use)
Add an attachment (proposed patch, testcase, etc.)

External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHSA-2011:0833	normal	SHIPPED_LIVE	Important: kernel security and bug fix update	2011-05-31 10:05:42 EDT

Groups: None (edit)

Description RHEL Product and Program Management 2011-03-23 08:14:26 EDT

This bug has been copied from bug #673242 and has been proposed
to be backported to 5.6 z-stream (EUS).

Comment 3 Phillip Lougher 2011-04-15 11:05:09 EDT

in kernel-2.6.18-238.10.1.el5

linux-2.6-virt-hypervisor-overflow-fix-for-clocks-4ghz.patch

Comment 6 errata-xmlrpc 2011-05-31 10:08:52 EDT

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-2011-0833.html

Comment 7 Martin Prpič 2011-06-02 09:28:15 EDT

    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:
Previously, on VMware, the time ran too fast on virtual machines with more than 4GHz TSC (Time Step Counter) processor frequency if they were using PIT/TSC based timekeeping. This was due to a calculation bug in the get_hypervisor_cycles_per_sec function. This update fixes the calculation, and timekeeping works correctly for such virtual machines

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