Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

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 1316420

Summary:	libvirtd crashed if set vcpusched vcpus over maxvcpu
Product:	Red Hat Enterprise Linux 7	Reporter:	Luyao Huang <lhuang>
Component:	libvirt	Assignee:	Peter Krempa <pkrempa>
Status:	CLOSED ERRATA	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	high	Docs Contact:
Priority:	high
Version:	7.3	CC:	jiyin, pkrempa, rbalakri
Target Milestone:	rc
Target Release:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:	libvirt-1.3.3-1.el7	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-11-03 18:39:12 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Luyao Huang 2016-03-10 07:58:57 UTC

Description of problem:
libvirtd sometimes crashed if set vcpusched vcpus over maxvcpu

Version-Release number of selected component (if applicable):
libvirt-1.3.2-1.el7.x86_64

How reproducible:
80%

Steps to Reproduce:
1. edit xml like this:
  <vcpu placement='auto' current='3'>4</vcpu>
  <cputune>
    <vcpupin vcpu='2' cpuset='1'/>
    <vcpusched vcpus='0-4' scheduler='batch'/>
  </cputune>

2. try it again and again
# virsh edit  rhel7.0-rhel
error: Disconnected from qemu:///system due to I/O error
error: End of file while reading data: Input/output error
Failed. Try again? [y,n,i,f,?]: 

3.

Actual results:
libvirtd crashed when vcpusched vcpus over maxvcpu

Expected results:
not crashed

Additional info:

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7f543aa73700 (LWP 380)]
0x00007f544a447d1c in _int_malloc () from /lib64/libc.so.6
(gdb) bt
#0  0x00007f544a447d1c in _int_malloc () from /lib64/libc.so.6
#1  0x00007f544a44987c in malloc () from /lib64/libc.so.6
#2  0x00007f544be9fd55 in xmlXPathNewCompExpr () from /lib64/libxml2.so.2
#3  0x00007f544be9ffeb in xmlXPathTryStreamCompile () from /lib64/libxml2.so.2
#4  0x00007f544beb2f8b in xmlXPathEvalExpr () from /lib64/libxml2.so.2
#5  0x00007f544beb3082 in xmlXPathEval () from /lib64/libxml2.so.2
#6  0x00007f544d17e5d2 in virXPathNodeSet (xpath=xpath@entry=0x7f544d336c6a "./cputune/iothreadsched", ctxt=ctxt@entry=0x7f5420005770, list=list@entry=0x7f543aa72870) at util/virxml.c:586
#7  0x00007f544d1b1f36 in virDomainDefParseXML (xml=xml@entry=0x7f54200027d0, root=root@entry=0x7f5420005930, ctxt=ctxt@entry=0x7f5420005770, caps=caps@entry=0x7f54281de1d0, xmlopt=xmlopt@entry=0x7f54281ea5a0, 
    flags=flags@entry=642) at conf/domain_conf.c:15195
#8  0x00007f544d1b7910 in virDomainDefParseNode (xml=xml@entry=0x7f54200027d0, root=0x7f5420005930, caps=caps@entry=0x7f54281de1d0, xmlopt=xmlopt@entry=0x7f54281ea5a0, flags=flags@entry=642)
    at conf/domain_conf.c:16567
#9  0x00007f544d1b7a28 in virDomainDefParse (
    xmlStr=xmlStr@entry=0x7f5420002e30 "<domain type='kvm'>\n  <name>rhel7.0-rhel</name>\n  <uuid>67c7a123-5415-4136-af62-a2ee098ba6cd</uuid>\n  <memory unit='KiB'>4048000</memory>\n  <currentMemory unit='KiB'>4048000</currentMemory>\n  <vcpu pl"..., filename=filename@entry=0x0, caps=caps@entry=0x7f54281de1d0, xmlopt=0x7f54281ea5a0, flags=flags@entry=642) at conf/domain_conf.c:16514
#10 0x00007f544d1b7a70 in virDomainDefParseString (
    xmlStr=xmlStr@entry=0x7f5420002e30 "<domain type='kvm'>\n  <name>rhel7.0-rhel</name>\n  <uuid>67c7a123-5415-4136-af62-a2ee098ba6cd</uuid>\n  <memory unit='KiB'>4048000</memory>\n  <currentMemory unit='KiB'>4048000</currentMemory>\n  <vcpu pl"..., caps=caps@entry=0x7f54281de1d0, xmlopt=<optimized out>, flags=flags@entry=642) at conf/domain_conf.c:16529
#11 0x00007f54342ced8c in qemuDomainDefineXMLFlags (conn=0x7f54240009a0, 
    xml=0x7f5420002e30 "<domain type='kvm'>\n  <name>rhel7.0-rhel</name>\n  <uuid>67c7a123-5415-4136-af62-a2ee098ba6cd</uuid>\n  <memory unit='KiB'>4048000</memory>\n  <currentMemory unit='KiB'>4048000</currentMemory>\n  <vcpu pl"..., flags=<optimized out>) at qemu/qemu_driver.c:7386
#12 0x00007f544d215c1a in virDomainDefineXMLFlags (conn=0x7f54240009a0, 
    xml=0x7f5420002e30 "<domain type='kvm'>\n  <name>rhel7.0-rhel</name>\n  <uuid>67c7a123-5415-4136-af62-a2ee098ba6cd</uuid>\n  <memory unit='KiB'>4048000</memory>\n  <currentMemory unit='KiB'>4048000</currentMemory>\n  <vcpu pl"..., flags=1) at libvirt-domain.c:6430
#13 0x00007f544de5af3a in remoteDispatchDomainDefineXMLFlags (server=0x7f544eb6eea0, msg=0x7f544eb87560, ret=0x7f5420001370, args=0x7f5420002a90, rerr=0x7f543aa72c30, client=0x7f544eb875d0)
    at remote_dispatch.h:3894
#14 remoteDispatchDomainDefineXMLFlagsHelper (server=0x7f544eb6eea0, client=0x7f544eb875d0, msg=0x7f544eb87560, rerr=0x7f543aa72c30, args=0x7f5420002a90, ret=0x7f5420001370) at remote_dispatch.h:3872
#15 0x00007f544d27f1f2 in virNetServerProgramDispatchCall (msg=0x7f544eb87560, client=0x7f544eb875d0, server=0x7f544eb6eea0, prog=0x7f544eb83440) at rpc/virnetserverprogram.c:437
#16 virNetServerProgramDispatch (prog=0x7f544eb83440, server=server@entry=0x7f544eb6eea0, client=0x7f544eb875d0, msg=0x7f544eb87560) at rpc/virnetserverprogram.c:307
#17 0x00007f544d27a41d in virNetServerProcessMsg (msg=<optimized out>, prog=<optimized out>, client=<optimized out>, srv=0x7f544eb6eea0) at rpc/virnetserver.c:135
#18 virNetServerHandleJob (jobOpaque=<optimized out>, opaque=0x7f544eb6eea0) at rpc/virnetserver.c:156
#19 0x00007f544d172df5 in virThreadPoolWorker (opaque=opaque@entry=0x7f544eb51160) at util/virthreadpool.c:145
#20 0x00007f544d172318 in virThreadHelper (data=<optimized out>) at util/virthread.c:206
#21 0x00007f544a799dc5 in start_thread () from /lib64/libpthread.so.0
#22 0x00007f544a4c01cd in clone () from /lib64/libc.so.6


==1050== Invalid read of size 4
==1050==    at 0x552364E: virDomainThreadSchedParseHelper (domain_conf.c:14603)
==1050==    by 0x554DF05: virDomainVcpuThreadSchedParse (domain_conf.c:14626)
==1050==    by 0x554DF05: virDomainDefParseXML (domain_conf.c:15190)
==1050==    by 0x555390F: virDomainDefParseNode (domain_conf.c:16567)
==1050==    by 0x5553A27: virDomainDefParse (domain_conf.c:16514)
==1050==    by 0x1E891D8B: qemuDomainDefineXMLFlags (qemu_driver.c:7386)
==1050==    by 0x55B1C19: virDomainDefineXMLFlags (libvirt-domain.c:6430)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlags (remote_dispatch.h:3894)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlagsHelper (remote_dispatch.h:3872)
==1050==    by 0x561B1F1: virNetServerProgramDispatchCall (virnetserverprogram.c:437)
==1050==    by 0x561B1F1: virNetServerProgramDispatch (virnetserverprogram.c:307)
==1050==    by 0x561641C: virNetServerProcessMsg (virnetserver.c:135)
==1050==    by 0x561641C: virNetServerHandleJob (virnetserver.c:156)
==1050==    by 0x550EDF4: virThreadPoolWorker (virthreadpool.c:145)
==1050==    by 0x550E317: virThreadHelper (virthread.c:206)
==1050==    by 0x805ADC4: start_thread (in /usr/lib64/libpthread-2.17.so)
==1050==  Address 0x2360f9b0 is 16 bytes after a block of size 96 alloc'd
==1050==    at 0x4C29BFD: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==1050==    by 0x4C2BACB: realloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==1050==    by 0x54AAEAF: virReallocN (viralloc.c:245)
==1050==    by 0x54AAF79: virExpandN (viralloc.c:294)
==1050==    by 0x552B4C1: virDomainDefSetVcpusMax (domain_conf.c:1308)
==1050==    by 0x554BBCE: virDomainVcpuParse (domain_conf.c:14675)
==1050==    by 0x554BBCE: virDomainDefParseXML (domain_conf.c:15028)
==1050==    by 0x555390F: virDomainDefParseNode (domain_conf.c:16567)
==1050==    by 0x5553A27: virDomainDefParse (domain_conf.c:16514)
==1050==    by 0x1E891D8B: qemuDomainDefineXMLFlags (qemu_driver.c:7386)
==1050==    by 0x55B1C19: virDomainDefineXMLFlags (libvirt-domain.c:6430)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlags (remote_dispatch.h:3894)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlagsHelper (remote_dispatch.h:3872)
==1050==    by 0x561B1F1: virNetServerProgramDispatchCall (virnetserverprogram.c:437)
==1050==    by 0x561B1F1: virNetServerProgramDispatch (virnetserverprogram.c:307)
==1050== 
==1050== Invalid write of size 4
==1050==    at 0x5523658: virDomainThreadSchedParseHelper (domain_conf.c:14610)
==1050==    by 0x554DF05: virDomainVcpuThreadSchedParse (domain_conf.c:14626)
==1050==    by 0x554DF05: virDomainDefParseXML (domain_conf.c:15190)
==1050==    by 0x555390F: virDomainDefParseNode (domain_conf.c:16567)
==1050==    by 0x5553A27: virDomainDefParse (domain_conf.c:16514)
==1050==    by 0x1E891D8B: qemuDomainDefineXMLFlags (qemu_driver.c:7386)
==1050==    by 0x55B1C19: virDomainDefineXMLFlags (libvirt-domain.c:6430)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlags (remote_dispatch.h:3894)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlagsHelper (remote_dispatch.h:3872)
==1050==    by 0x561B1F1: virNetServerProgramDispatchCall (virnetserverprogram.c:437)
==1050==    by 0x561B1F1: virNetServerProgramDispatch (virnetserverprogram.c:307)
==1050==    by 0x561641C: virNetServerProcessMsg (virnetserver.c:135)
==1050==    by 0x561641C: virNetServerHandleJob (virnetserver.c:156)
==1050==    by 0x550EDF4: virThreadPoolWorker (virthreadpool.c:145)
==1050==    by 0x550E317: virThreadHelper (virthread.c:206)
==1050==    by 0x805ADC4: start_thread (in /usr/lib64/libpthread-2.17.so)
==1050==  Address 0x2360f9b0 is 16 bytes after a block of size 96 alloc'd
==1050==    at 0x4C29BFD: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==1050==    by 0x4C2BACB: realloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==1050==    by 0x54AAEAF: virReallocN (viralloc.c:245)
==1050==    by 0x54AAF79: virExpandN (viralloc.c:294)
==1050==    by 0x552B4C1: virDomainDefSetVcpusMax (domain_conf.c:1308)
==1050==    by 0x554BBCE: virDomainVcpuParse (domain_conf.c:14675)
==1050==    by 0x554BBCE: virDomainDefParseXML (domain_conf.c:15028)
==1050==    by 0x555390F: virDomainDefParseNode (domain_conf.c:16567)
==1050==    by 0x5553A27: virDomainDefParse (domain_conf.c:16514)
==1050==    by 0x1E891D8B: qemuDomainDefineXMLFlags (qemu_driver.c:7386)
==1050==    by 0x55B1C19: virDomainDefineXMLFlags (libvirt-domain.c:6430)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlags (remote_dispatch.h:3894)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlagsHelper (remote_dispatch.h:3872)
==1050==    by 0x561B1F1: virNetServerProgramDispatchCall (virnetserverprogram.c:437)
==1050==    by 0x561B1F1: virNetServerProgramDispatch (virnetserverprogram.c:307)
==1050== 
==1050== Invalid write of size 4
==1050==    at 0x552365A: virDomainThreadSchedParseHelper (domain_conf.c:14611)
==1050==    by 0x554DF05: virDomainVcpuThreadSchedParse (domain_conf.c:14626)
==1050==    by 0x554DF05: virDomainDefParseXML (domain_conf.c:15190)
==1050==    by 0x555390F: virDomainDefParseNode (domain_conf.c:16567)
==1050==    by 0x5553A27: virDomainDefParse (domain_conf.c:16514)
==1050==    by 0x1E891D8B: qemuDomainDefineXMLFlags (qemu_driver.c:7386)
==1050==    by 0x55B1C19: virDomainDefineXMLFlags (libvirt-domain.c:6430)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlags (remote_dispatch.h:3894)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlagsHelper (remote_dispatch.h:3872)
==1050==    by 0x561B1F1: virNetServerProgramDispatchCall (virnetserverprogram.c:437)
==1050==    by 0x561B1F1: virNetServerProgramDispatch (virnetserverprogram.c:307)
==1050==    by 0x561641C: virNetServerProcessMsg (virnetserver.c:135)
==1050==    by 0x561641C: virNetServerHandleJob (virnetserver.c:156)
==1050==    by 0x550EDF4: virThreadPoolWorker (virthreadpool.c:145)
==1050==    by 0x550E317: virThreadHelper (virthread.c:206)
==1050==    by 0x805ADC4: start_thread (in /usr/lib64/libpthread-2.17.so)
==1050==  Address 0x2360f9b4 is 20 bytes after a block of size 96 alloc'd
==1050==    at 0x4C29BFD: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==1050==    by 0x4C2BACB: realloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==1050==    by 0x54AAEAF: virReallocN (viralloc.c:245)
==1050==    by 0x54AAF79: virExpandN (viralloc.c:294)
==1050==    by 0x552B4C1: virDomainDefSetVcpusMax (domain_conf.c:1308)
==1050==    by 0x554BBCE: virDomainVcpuParse (domain_conf.c:14675)
==1050==    by 0x554BBCE: virDomainDefParseXML (domain_conf.c:15028)
==1050==    by 0x555390F: virDomainDefParseNode (domain_conf.c:16567)
==1050==    by 0x5553A27: virDomainDefParse (domain_conf.c:16514)
==1050==    by 0x1E891D8B: qemuDomainDefineXMLFlags (qemu_driver.c:7386)
==1050==    by 0x55B1C19: virDomainDefineXMLFlags (libvirt-domain.c:6430)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlags (remote_dispatch.h:3894)
==1050==    by 0x120F39: remoteDispatchDomainDefineXMLFlagsHelper (remote_dispatch.h:3872)
==1050==    by 0x561B1F1: virNetServerProgramDispatchCall (virnetserverprogram.c:437)
==1050==    by 0x561B1F1: virNetServerProgramDispatch (virnetserverprogram.c:307)
==1050==

Comment 1 Peter Krempa 2016-03-10 13:03:59 UTC

Fixed upstream:

commit 8c7b7c4b0bb0d58dfb2e3dcdf1855a7dc9c858d0
Author: Peter Krempa <pkrempa>
Date:   Thu Mar 10 09:46:53 2016 +0100

    conf: Fix off-by-one in virDomainDefGetVcpu
    
    Cpus are indexed starting from '0' so the check was invalid.
    
    Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1316384
    Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1316420

v1.3.2-101-g8c7b7c4

Comment 2 Mike McCune 2016-03-28 23:19:36 UTC

This bug was accidentally moved from POST to MODIFIED via an error in automation, please see mmccune with any questions

Comment 4 Luyao Huang 2016-08-09 02:45:16 UTC

verify this bug with libvirt-2.0.0-4.el7.x86_64:

1. open a terminal to run libvirtd under valgrind:

# valgrind --leak-check=full libvirtd
==1352== Memcheck, a memory error detector
==1352== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==1352== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==1352== Command: libvirtd

2. edit guest xml in another terminal:

# virsh edit r7

  <vcpu placement='auto' current='6'>10</vcpu>
  <cputune>
    <vcpupin vcpu='2' cpuset='1'/>
    <vcpusched vcpus='0-10' scheduler='batch'/>
  </cputune>

error: unsupported configuration: vCPU '10' is not present in domain definition
Failed. Try again? [y,n,i,f,?]: 

3. no invalid memory access in valgrind report and libvirtd not crash

Comment 6 errata-xmlrpc 2016-11-03 18:39:12 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHSA-2016-2577.html