[libvirt] [PATCH v1 01/21] qemu: Create hugepage path on per domain basis
Michal Privoznik
mprivozn at redhat.com
Thu Nov 24 14:47:50 UTC 2016
If you've ever tried running a huge page backed guest under
different user than root, you probably failed. Problem is even
though we have corresponding APIs in the security drivers,
there's no implementation and thus we don't relabel the huge page
path. But even if we did, so far all of the domains share the
same path:
/hugepageMount/libvirt/qemu
Our only option there would be to set 0777 mode on the qemu dir
which is totally unsafe. Therefore, we can create dir on
per-domain basis, i.e.:
/hugepageMount/libvirt/qemu/domainName
and chown domainName dir to the user that domain is configured to
run under.
Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
src/qemu/qemu_command.c | 4 +-
src/qemu/qemu_conf.c | 45 ++++++++++++++++------
src/qemu/qemu_conf.h | 16 +++++---
src/qemu/qemu_driver.c | 19 +++------
src/qemu/qemu_process.c | 25 +++++++++++-
.../qemuxml2argv-hugepages-numa.args | 4 +-
.../qemuxml2argv-hugepages-pages.args | 14 +++----
.../qemuxml2argv-hugepages-pages2.args | 2 +-
.../qemuxml2argv-hugepages-pages3.args | 2 +-
.../qemuxml2argv-hugepages-pages5.args | 2 +-
.../qemuxml2argv-hugepages-shared.args | 12 +++---
tests/qemuxml2argvdata/qemuxml2argv-hugepages.args | 2 +-
.../qemuxml2argv-memory-hotplug-dimm-addr.args | 4 +-
.../qemuxml2argv-memory-hotplug-dimm.args | 4 +-
14 files changed, 97 insertions(+), 58 deletions(-)
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 51b5aaf..becdce4 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3303,7 +3303,7 @@ qemuBuildMemoryBackendStr(unsigned long long size,
return -1;
if (pagesize) {
- if (qemuGetHupageMemPath(cfg, pagesize, &mem_path) < 0)
+ if (qemuGetDomainHupageMemPath(def, cfg, pagesize, &mem_path) < 0)
goto cleanup;
*backendType = "memory-backend-file";
@@ -7177,7 +7177,7 @@ qemuBuildMemPathStr(virQEMUDriverConfigPtr cfg,
return -1;
}
- if (qemuGetHupageMemPath(cfg, def->mem.hugepages[0].size, &mem_path) < 0)
+ if (qemuGetDomainHupageMemPath(def, cfg, def->mem.hugepages[0].size, &mem_path) < 0)
return -1;
virCommandAddArgList(cmd, "-mem-prealloc", "-mem-path", mem_path, NULL);
diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
index fbac3ea..9be5b60 100644
--- a/src/qemu/qemu_conf.c
+++ b/src/qemu/qemu_conf.c
@@ -1456,7 +1456,7 @@ qemuTranslateSnapshotDiskSourcePool(virConnectPtr conn ATTRIBUTE_UNUSED,
}
char *
-qemuGetHugepagePath(virHugeTLBFSPtr hugepage)
+qemuGetBaseHugepagePath(virHugeTLBFSPtr hugepage)
{
char *ret;
@@ -1467,8 +1467,26 @@ qemuGetHugepagePath(virHugeTLBFSPtr hugepage)
}
+char *
+qemuGetDomainHugepagePath(const virDomainDef *def,
+ virHugeTLBFSPtr hugepage)
+{
+ char *base = qemuGetBaseHugepagePath(hugepage);
+ char *ret;
+
+ if (!base ||
+ virAsprintf(&ret, "%s/%s", base, def->name) < 0) {
+ VIR_FREE(base);
+ return NULL;
+ }
+
+ return ret;
+}
+
+
/**
- * qemuGetDefaultHugepath:
+ * qemuGetDomainDefaultHugepath:
+ * @def: domain definition
* @hugetlbfs: array of configured hugepages
* @nhugetlbfs: number of item in the array
*
@@ -1477,8 +1495,9 @@ qemuGetHugepagePath(virHugeTLBFSPtr hugepage)
* Returns 0 on success, -1 otherwise.
* */
char *
-qemuGetDefaultHugepath(virHugeTLBFSPtr hugetlbfs,
- size_t nhugetlbfs)
+qemuGetDomainDefaultHugepath(const virDomainDef *def,
+ virHugeTLBFSPtr hugetlbfs,
+ size_t nhugetlbfs)
{
size_t i;
@@ -1489,12 +1508,12 @@ qemuGetDefaultHugepath(virHugeTLBFSPtr hugetlbfs,
if (i == nhugetlbfs)
i = 0;
- return qemuGetHugepagePath(&hugetlbfs[i]);
+ return qemuGetDomainHugepagePath(def, &hugetlbfs[i]);
}
/**
- * qemuGetHupageMemPath: Construct HP enabled memory backend path
+ * qemuGetDomainHupageMemPath: Construct HP enabled memory backend path
*
* If no specific hugepage size is requested (@pagesize is zero)
* the default hugepage size is used).
@@ -1504,9 +1523,10 @@ qemuGetDefaultHugepath(virHugeTLBFSPtr hugetlbfs,
* -1 otherwise.
*/
int
-qemuGetHupageMemPath(virQEMUDriverConfigPtr cfg,
- unsigned long long pagesize,
- char **memPath)
+qemuGetDomainHupageMemPath(const virDomainDef *def,
+ virQEMUDriverConfigPtr cfg,
+ unsigned long long pagesize,
+ char **memPath)
{
size_t i = 0;
@@ -1518,8 +1538,9 @@ qemuGetHupageMemPath(virQEMUDriverConfigPtr cfg,
}
if (!pagesize) {
- if (!(*memPath = qemuGetDefaultHugepath(cfg->hugetlbfs,
- cfg->nhugetlbfs)))
+ if (!(*memPath = qemuGetDomainDefaultHugepath(def,
+ cfg->hugetlbfs,
+ cfg->nhugetlbfs)))
return -1;
} else {
for (i = 0; i < cfg->nhugetlbfs; i++) {
@@ -1535,7 +1556,7 @@ qemuGetHupageMemPath(virQEMUDriverConfigPtr cfg,
return -1;
}
- if (!(*memPath = qemuGetHugepagePath(&cfg->hugetlbfs[i])))
+ if (!(*memPath = qemuGetDomainHugepagePath(def, &cfg->hugetlbfs[i])))
return -1;
}
diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h
index f6e3257..d191e10 100644
--- a/src/qemu/qemu_conf.h
+++ b/src/qemu/qemu_conf.h
@@ -335,11 +335,15 @@ virDomainXMLOptionPtr virQEMUDriverCreateXMLConf(virQEMUDriverPtr driver);
int qemuTranslateSnapshotDiskSourcePool(virConnectPtr conn,
virDomainSnapshotDiskDefPtr def);
-char * qemuGetHugepagePath(virHugeTLBFSPtr hugepage);
-char * qemuGetDefaultHugepath(virHugeTLBFSPtr hugetlbfs,
- size_t nhugetlbfs);
+char * qemuGetBaseHugepagePath(virHugeTLBFSPtr hugepage);
+char * qemuGetDomainHugepagePath(const virDomainDef *def,
+ virHugeTLBFSPtr hugepage);
+char * qemuGetDomainDefaultHugepath(const virDomainDef *def,
+ virHugeTLBFSPtr hugetlbfs,
+ size_t nhugetlbfs);
-int qemuGetHupageMemPath(virQEMUDriverConfigPtr cfg,
- unsigned long long pagesize,
- char **memPath);
+int qemuGetDomainHupageMemPath(const virDomainDef *def,
+ virQEMUDriverConfigPtr cfg,
+ unsigned long long pagesize,
+ char **memPath);
#endif /* __QEMUD_CONF_H */
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index fdfe912..8c8f969 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -852,7 +852,7 @@ qemuStateInitialize(bool privileged,
* it, since we can't assume the root mount point has permissions that
* will let our spawned QEMU instances use it. */
for (i = 0; i < cfg->nhugetlbfs; i++) {
- hugepagePath = qemuGetHugepagePath(&cfg->hugetlbfs[i]);
+ hugepagePath = qemuGetBaseHugepagePath(&cfg->hugetlbfs[i]);
if (!hugepagePath)
goto error;
@@ -863,19 +863,10 @@ qemuStateInitialize(bool privileged,
hugepagePath);
goto error;
}
- if (privileged) {
- if (virFileUpdatePerm(cfg->hugetlbfs[i].mnt_dir,
- 0, S_IXGRP | S_IXOTH) < 0)
- goto error;
- if (chown(hugepagePath, cfg->user, cfg->group) < 0) {
- virReportSystemError(errno,
- _("unable to set ownership on %s to %d:%d"),
- hugepagePath,
- (int) cfg->user,
- (int) cfg->group);
- goto error;
- }
- }
+ if (privileged &&
+ virFileUpdatePerm(cfg->hugetlbfs[i].mnt_dir,
+ 0, S_IXGRP | S_IXOTH) < 0)
+ goto error;
VIR_FREE(hugepagePath);
}
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index f8f379a..93a38e1 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -5264,11 +5264,19 @@ qemuProcessPrepareHost(virQEMUDriverPtr driver,
if (vm->def->mem.nhugepages) {
for (i = 0; i < cfg->nhugetlbfs; i++) {
- char *hugepagePath = qemuGetHugepagePath(&cfg->hugetlbfs[i]);
+ char *hugepagePath = qemuGetDomainHugepagePath(vm->def, &cfg->hugetlbfs[i]);
if (!hugepagePath)
goto cleanup;
+ if (virFileMakePathWithMode(hugepagePath, 0700) < 0) {
+ virReportSystemError(errno,
+ _("Unable to create %s"),
+ hugepagePath);
+ VIR_FREE(hugepagePath);
+ goto cleanup;
+ }
+
if (virSecurityManagerSetHugepages(driver->securityManager,
vm->def, hugepagePath) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -6129,6 +6137,21 @@ void qemuProcessStop(virQEMUDriverPtr driver,
networkReleaseActualDevice(vm->def, net);
}
+ if (vm->def->mem.nhugepages) {
+ for (i = 0; i < cfg->nhugetlbfs; i++) {
+ char *hugepagePath = qemuGetDomainHugepagePath(vm->def, &cfg->hugetlbfs[i]);
+
+ if (!hugepagePath)
+ continue;
+
+ if (rmdir(hugepagePath) < 0)
+ VIR_WARN("Unable to remove hugepage path: %s (errno=%d)",
+ hugepagePath, errno);
+
+ VIR_FREE(hugepagePath);
+ }
+ }
+
retry:
if ((ret = qemuRemoveCgroup(vm)) < 0) {
if (ret == -EBUSY && (retries++ < 5)) {
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-numa.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-numa.args
index 7b90784..bd562a8 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-numa.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-numa.args
@@ -11,10 +11,10 @@ QEMU_AUDIO_DRV=spice \
-m size=1048576k,slots=16,maxmem=1099511627776k \
-smp 2,sockets=2,cores=1,threads=1 \
-mem-prealloc \
--mem-path /dev/hugepages2M/libvirt/qemu \
+-mem-path /dev/hugepages2M/libvirt/qemu/fedora \
-numa node,nodeid=0,cpus=0-1,mem=1024 \
-object memory-backend-file,id=memdimm0,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=1-3,\
+mem-path=/dev/hugepages1G/libvirt/qemu/fedora,size=1073741824,host-nodes=1-3,\
policy=bind \
-device pc-dimm,node=0,memdev=memdimm0,id=dimm0,slot=0 \
-uuid 63840878-0deb-4095-97e6-fc444d9bc9fa \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args
index 9f0e696..e0aa151 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages.args
@@ -11,19 +11,19 @@ QEMU_AUDIO_DRV=none \
-m 4096 \
-smp 4,sockets=4,cores=1,threads=1 \
-object memory-backend-file,id=ram-node0,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=0-3,\
-policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu/QEMUGuest1,size=1073741824,\
+host-nodes=0-3,policy=bind \
-numa node,nodeid=0,cpus=0,memdev=ram-node0 \
-object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,size=1073741824,host-nodes=0-3,\
-policy=bind \
+mem-path=/dev/hugepages2M/libvirt/qemu/QEMUGuest1,size=1073741824,\
+host-nodes=0-3,policy=bind \
-numa node,nodeid=1,cpus=1,memdev=ram-node1 \
-object memory-backend-file,id=ram-node2,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=0-3,\
-policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu/QEMUGuest1,size=1073741824,\
+host-nodes=0-3,policy=bind \
-numa node,nodeid=2,cpus=2,memdev=ram-node2 \
-object memory-backend-file,id=ram-node3,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=3,\
+mem-path=/dev/hugepages1G/libvirt/qemu/QEMUGuest1,size=1073741824,host-nodes=3,\
policy=bind \
-numa node,nodeid=3,cpus=3,memdev=ram-node3 \
-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
index a37f03d..b4cd088 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages2.args
@@ -11,7 +11,7 @@ QEMU_AUDIO_DRV=none \
-m 1024 \
-smp 2,sockets=2,cores=1,threads=1 \
-mem-prealloc \
--mem-path /dev/hugepages2M/libvirt/qemu \
+-mem-path /dev/hugepages2M/libvirt/qemu/SomeDummyHugepagesGuest \
-numa node,nodeid=0,cpus=0,mem=256 \
-numa node,nodeid=1,cpus=1,mem=768 \
-uuid ef1bdff4-27f3-4e85-a807-5fb4d58463cc \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
index 57dd3fa..bf28d74 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages3.args
@@ -13,7 +13,7 @@ QEMU_AUDIO_DRV=none \
-object memory-backend-ram,id=ram-node0,size=268435456 \
-numa node,nodeid=0,cpus=0,memdev=ram-node0 \
-object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=805306368 \
+mem-path=/dev/hugepages1G/libvirt/qemu/SomeDummyHugepagesGuest,size=805306368 \
-numa node,nodeid=1,cpus=1,memdev=ram-node1 \
-uuid ef1bdff4-27f3-4e85-a807-5fb4d58463cc \
-nographic \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args
index a826149..a0a6506 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-pages5.args
@@ -10,7 +10,7 @@ QEMU_AUDIO_DRV=none \
-M pc \
-m 1024 \
-mem-prealloc \
--mem-path /dev/hugepages2M/libvirt/qemu \
+-mem-path /dev/hugepages2M/libvirt/qemu/SomeDummyHugepagesGuest \
-smp 2,sockets=2,cores=1,threads=1 \
-uuid ef1bdff4-27f3-4e85-a807-5fb4d58463cc \
-nographic \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args
index f9fc218..03d736a 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages-shared.args
@@ -11,19 +11,19 @@ QEMU_AUDIO_DRV=none \
-m 4096 \
-smp 4,sockets=4,cores=1,threads=1 \
-object memory-backend-file,id=ram-node0,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=0-3,\
-policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu/QEMUGuest1,size=1073741824,\
+host-nodes=0-3,policy=bind \
-numa node,nodeid=0,cpus=0,memdev=ram-node0 \
-object memory-backend-file,id=ram-node1,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,share=yes,size=1073741824,\
+mem-path=/dev/hugepages2M/libvirt/qemu/QEMUGuest1,share=yes,size=1073741824,\
host-nodes=0-3,policy=bind \
-numa node,nodeid=1,cpus=1,memdev=ram-node1 \
-object memory-backend-file,id=ram-node2,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,share=no,size=1073741824,host-nodes=0-3,\
-policy=bind \
+mem-path=/dev/hugepages1G/libvirt/qemu/QEMUGuest1,share=no,size=1073741824,\
+host-nodes=0-3,policy=bind \
-numa node,nodeid=2,cpus=2,memdev=ram-node2 \
-object memory-backend-file,id=ram-node3,prealloc=yes,\
-mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=3,\
+mem-path=/dev/hugepages1G/libvirt/qemu/QEMUGuest1,size=1073741824,host-nodes=3,\
policy=bind \
-numa node,nodeid=3,cpus=3,memdev=ram-node3 \
-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-hugepages.args b/tests/qemuxml2argvdata/qemuxml2argv-hugepages.args
index 361c8e5..2d437da 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-hugepages.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-hugepages.args
@@ -10,7 +10,7 @@ QEMU_AUDIO_DRV=none \
-M pc \
-m 214 \
-mem-prealloc \
--mem-path /dev/hugepages2M/libvirt/qemu \
+-mem-path /dev/hugepages2M/libvirt/qemu/QEMUGuest1 \
-smp 1,sockets=1,cores=1,threads=1 \
-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
-nographic \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm-addr.args b/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm-addr.args
index fdbb4c3..b635327 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm-addr.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm-addr.args
@@ -12,8 +12,8 @@ QEMU_AUDIO_DRV=none \
-smp 2,sockets=2,cores=1,threads=1 \
-numa node,nodeid=0,cpus=0-1,mem=214 \
-object memory-backend-file,id=memdimm0,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,size=536870912,host-nodes=1-3,\
-policy=bind \
+mem-path=/dev/hugepages2M/libvirt/qemu/QEMUGuest1,size=536870912,\
+host-nodes=1-3,policy=bind \
-device pc-dimm,node=0,memdev=memdimm0,id=dimm0,slot=0,addr=4294967296 \
-object memory-backend-ram,id=memdimm2,size=536870912 \
-device pc-dimm,node=0,memdev=memdimm2,id=dimm2,slot=2 \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm.args b/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm.args
index 1587aba..10d8593 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm.args
@@ -14,8 +14,8 @@ QEMU_AUDIO_DRV=none \
-object memory-backend-ram,id=memdimm0,size=536870912 \
-device pc-dimm,node=0,memdev=memdimm0,id=dimm0,slot=0 \
-object memory-backend-file,id=memdimm1,prealloc=yes,\
-mem-path=/dev/hugepages2M/libvirt/qemu,size=536870912,host-nodes=1-3,\
-policy=bind \
+mem-path=/dev/hugepages2M/libvirt/qemu/QEMUGuest1,size=536870912,\
+host-nodes=1-3,policy=bind \
-device pc-dimm,node=0,memdev=memdimm1,id=dimm1,slot=1 \
-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
-nographic \
--
2.8.4
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