12:55 a.m.
When trying to migrate a huge page enabled guest, I've noticed
the following crash. Apparently, if no specific hugepages are
requested:
<memoryBacking>
<hugepages/>
</memoryBacking>
and there are no hugepages configured on the destination, we try
to dereference a NULL pointer.
Program received signal SIGSEGV, Segmentation fault.
0x00007fcc907fb20e in qemuGetHugepagePath (hugepage=0x0) at qemu/qemu_conf.c:1447
1447 if (virAsprintf(&ret, "%s/libvirt/qemu", hugepage->mnt_dir)
< 0)
(gdb) bt
#0 0x00007fcc907fb20e in qemuGetHugepagePath (hugepage=0x0) at qemu/qemu_conf.c:1447
#1 0x00007fcc907fb2f5 in qemuGetDefaultHugepath (hugetlbfs=0x0, nhugetlbfs=0) at
qemu/qemu_conf.c:1466
#2 0x00007fcc907b4afa in qemuBuildMemoryBackendStr (size=4194304, pagesize=0,
guestNode=0, userNodeset=0x0, autoNodeset=0x0, def=0x7fcc70019070,
qemuCaps=0x7fcc70004000, cfg=0x7fcc5c011800, backendType=0x7fcc95087228,
backendProps=0x7fcc95087218,
force=false) at qemu/qemu_command.c:3297
#3 0x00007fcc907b4f91 in qemuBuildMemoryCellBackendStr (def=0x7fcc70019070,
qemuCaps=0x7fcc70004000, cfg=0x7fcc5c011800, cell=0, auto_nodeset=0x0,
backendStr=0x7fcc70020360) at qemu/qemu_command.c:3413
#4 0x00007fcc907c0406 in qemuBuildNumaArgStr (cfg=0x7fcc5c011800, def=0x7fcc70019070,
cmd=0x7fcc700040c0, qemuCaps=0x7fcc70004000, auto_nodeset=0x0) at
qemu/qemu_command.c:7470
#5 0x00007fcc907c5fdf in qemuBuildCommandLine (driver=0x7fcc5c07b8a0,
logManager=0x7fcc70003c00, def=0x7fcc70019070, monitor_chr=0x7fcc70004bb0,
monitor_json=true, qemuCaps=0x7fcc70004000, migrateURI=0x7fcc700199c0 "defer",
snapshot=0x0,
vmop=VIR_NETDEV_VPORT_PROFILE_OP_MIGRATE_IN_START, standalone=false, enableFips=false,
nodeset=0x0, nnicindexes=0x7fcc95087498, nicindexes=0x7fcc950874a0,
domainLibDir=0x7fcc700047c0 "/var/lib/libvirt/qemu/domain-1-fedora") at
qemu/qemu_command.c:9547
#6 0x00007fcc90807d37 in qemuProcessLaunch (conn=0x7fcc54000b10, driver=0x7fcc5c07b8a0,
vm=0x7fcc70005320, asyncJob=QEMU_ASYNC_JOB_MIGRATION_IN, incoming=0x7fcc70015d70,
snapshot=0x0, vmop=VIR_NETDEV_VPORT_PROFILE_OP_MIGRATE_IN_START, flags=4)
at qemu/qemu_process.c:5238
#7 0x00007fcc90815233 in qemuMigrationPrepareAny (driver=0x7fcc5c07b8a0,
dconn=0x7fcc54000b10,
cookiein=0x7fcc70001ec0 "<qemu-migration>\n
<name>fedora</name>\n
<uuid>63840878-0deb-4095-97e6-fc444d9bc9fa</uuid>\n
<hostname>lisa</hostname>\n
<hostuuid>da1c2801-52f3-11cb-a9db-e905fe22010c</hostuuid>\n <feature
name='lock"..., cookieinlen=328,
cookieout=0x7fcc95087aa0, cookieoutlen=0x7fcc95087a90, def=0x7fcc950878f0,
origname=0x0, st=0x0, protocol=0x7fcc908ab42f "tcp", port=49152, autoPort=true,
listenAddress=0x0, nmigrate_disks=0, migrate_disks=0x0, nbdPort=0,
compression=0x7fcc70000a30,
flags=64) at qemu/qemu_migration.c:3752
#8 0x00007fcc908161ae in qemuMigrationPrepareDirect (driver=0x7fcc5c07b8a0,
dconn=0x7fcc54000b10,
cookiein=0x7fcc70001ec0 "<qemu-migration>\n
<name>fedora</name>\n
<uuid>63840878-0deb-4095-97e6-fc444d9bc9fa</uuid>\n
<hostname>lisa</hostname>\n
<hostuuid>da1c2801-52f3-11cb-a9db-e905fe22010c</hostuuid>\n <feature
name='lock"..., cookieinlen=328,
cookieout=0x7fcc95087aa0, cookieoutlen=0x7fcc95087a90, uri_in=0x0,
uri_out=0x7fcc700008c0, def=0x7fcc950878f0, origname=0x0, listenAddress=0x0,
nmigrate_disks=0, migrate_disks=0x0, nbdPort=0, compression=0x7fcc70000a30, flags=64)
at qemu/qemu_migration.c:4100
#9 0x00007fcc908673f3 in qemuDomainMigratePrepare3Params (dconn=0x7fcc54000b10,
params=0x7fcc70000930, nparams=1,
cookiein=0x7fcc70001ec0 "<qemu-migration>\n
<name>fedora</name>\n
<uuid>63840878-0deb-4095-97e6-fc444d9bc9fa</uuid>\n
<hostname>lisa</hostname>\n
<hostuuid>da1c2801-52f3-11cb-a9db-e905fe22010c</hostuuid>\n <feature
name='lock"..., cookieinlen=328,
cookieout=0x7fcc95087aa0, cookieoutlen=0x7fcc95087a90, uri_out=0x7fcc700008c0,
flags=64) at qemu/qemu_driver.c:12204
#10 0x00007fcc9d5499da in virDomainMigratePrepare3Params (dconn=0x7fcc54000b10,
params=0x7fcc70000930, nparams=1,
cookiein=0x7fcc70001ec0 "<qemu-migration>\n
<name>fedora</name>\n
<uuid>63840878-0deb-4095-97e6-fc444d9bc9fa</uuid>\n
<hostname>lisa</hostname>\n
<hostuuid>da1c2801-52f3-11cb-a9db-e905fe22010c</hostuuid>\n <feature
name='lock"..., cookieinlen=328,
cookieout=0x7fcc95087aa0, cookieoutlen=0x7fcc95087a90, uri_out=0x7fcc700008c0,
flags=64) at libvirt-domain.c:5141
#11 0x000055c71ce1c9f5 in remoteDispatchDomainMigratePrepare3Params
(server=0x55c71f0a0cc0, client=0x55c71f0bef20, msg=0x55c71f0ae460, rerr=0x7fcc95087b80,
args=0x7fcc70000900, ret=0x7fcc70000af0) at remote.c:5117
#12 0x000055c71cdfbd9e in remoteDispatchDomainMigratePrepare3ParamsHelper
(server=0x55c71f0a0cc0, client=0x55c71f0bef20, msg=0x55c71f0ae460, rerr=0x7fcc95087b80,
args=0x7fcc70000900, ret=0x7fcc70000af0) at remote_dispatch.h:7820
#13 0x00007fcc9d5cd810 in virNetServerProgramDispatchCall (prog=0x55c71f0ad070,
server=0x55c71f0a0cc0, client=0x55c71f0bef20, msg=0x55c71f0ae460) at
rpc/virnetserverprogram.c:437
#14 0x00007fcc9d5cd371 in virNetServerProgramDispatch (prog=0x55c71f0ad070,
server=0x55c71f0a0cc0, client=0x55c71f0bef20, msg=0x55c71f0ae460) at
rpc/virnetserverprogram.c:307
#15 0x000055c71ce35903 in virNetServerProcessMsg (srv=0x55c71f0a0cc0,
client=0x55c71f0bef20, prog=0x55c71f0ad070, msg=0x55c71f0ae460) at rpc/virnetserver.c:148
#16 0x000055c71ce359c3 in virNetServerHandleJob (jobOpaque=0x55c71f0aef30,
opaque=0x55c71f0a0cc0) at rpc/virnetserver.c:169
#17 0x00007fcc9d47a6f3 in virThreadPoolWorker (opaque=0x55c71f0ae540) at
util/virthreadpool.c:167
#18 0x00007fcc9d479c95 in virThreadHelper (data=0x55c71f0ae560) at util/virthread.c:206
#19 0x00007fcc9aabd494 in start_thread () from /lib64/libpthread.so.0
#20 0x00007fcc9a8025dd in clone () from /lib64/libc.so.6
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/qemu/qemu_command.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 038c38f..0bafc3f 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3294,6 +3294,12 @@ qemuBuildMemoryBackendStr(unsigned long long size,
if (!(mem_path = qemuGetHugepagePath(&cfg->hugetlbfs[i])))
goto cleanup;
} else {
+ if (!cfg->nhugetlbfs) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ "%s", _("hugetlbfs filesystem is not
mounted "
+ "or disabled by administrator
config"));
+ goto cleanup;
+ }
if (!(mem_path = qemuGetDefaultHugepath(cfg->hugetlbfs,
cfg->nhugetlbfs)))
goto cleanup;
--
2.8.4