Bug 1240771

Summary: Installing a new kernel causes garbage to be added to grub.cfg
Product: Red Hat Enterprise Linux 7 Reporter: Luiz Capitulino <lcapitulino>
Component: tunedAssignee: Jaroslav Škarvada <jskarvad>
Status: CLOSED DUPLICATE QA Contact: qe-baseos-daemons
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 7.2CC: jeder, jskarvad
Target Milestone: rc   
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Hardware: Unspecified   
OS: Unspecified   
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Last Closed: 2015-07-16 11:51:54 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Blocks: 1240765    
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Description Flags
grub.cfg with garbage none

Description Luiz Capitulino 2015-07-07 17:26:26 UTC 
Created attachment 1049504 [details]
grub.cfg with garbage

Description of problem:

Installing a new kernel on a system using the realtime-virtual-host profile causes tuned to add garbage to the grub.cfg file. The garbage is added to the "set tuned_param" line, like:

### BEGIN /etc/grub.d/00_tuned ###
set tuned_params="isolcpus=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,12,13,14,15,8,10,12,14=1,3,5,7,9,11,1
[...]

This goes on and on for several lines. I'll attach the full grub.cfg for inspection.

A system with this grub.cfg won't boot. GRUB will print an error message before printing its prompt. The only way around this I could find was to boot with a rescue DVD and re-generate the grub.cfg file by hand.

Version-Release number of selected component (if applicable): tuned-2.4.1-1.20150622git740fab40.el7.noarch


How reproducible:


Steps to Reproduce:
1. Install the realtime-virtual-host profile from (https://github.com/jeremyeder/tuned-profiles-realtime)
2. Install a new kernel
Comment 1 Jeremy Eder 2015-07-13 20:20:53 UTC 
I have seen something very similar....never figured out how to reproduce it.

https://bugzilla.redhat.com/show_bug.cgi?id=1152550
Comment 2 Jaroslav Škarvada 2015-07-16 11:42:48 UTC 
I think it is a race somewhere, e.g. the grub.cfg is probably simultaneously modified by two different processes. The source of this problem is currently unknown to me and I wasn't able to reproduce it, but I am still trying.
Comment 3 Jeremy Eder 2015-07-16 11:51:54 UTC 
Let's move to the original BZ 1152550.  I just put a new comment there.

*** This bug has been marked as a duplicate of bug 1152550 ***