From f901375a7380837428cbbc80d24e4bb7b91db427 Mon Sep 17 00:00:00 2001

Message-Id: <f901375a7380837428cbbc80d24e4bb7b91db427@dist-git>

From: Jiri Denemark <jdenemar@redhat.com>

Date: Fri, 16 Aug 2019 14:52:28 +0200

Subject: [PATCH] qemu: Pass qemuCaps to qemuDomainDefFormatBufInternal

MIME-Version: 1.0

Content-Type: text/plain; charset=UTF-8

Content-Transfer-Encoding: 8bit

Since qemuDomainDefPostParse callback requires qemuCaps, we need to make

sure it gets the capabilities stored in the domain's private data if the

domain is running. Passing NULL may cause QEMU capabilities probing to

be triggered in case QEMU binary changed in the meantime. When this

happens while a running domain object is locked, QMP event delivered to

the domain before QEMU capabilities probing finishes will deadlock the

event loop.

This patch fixes all paths leading to qemuDomainDefFormatBufInternal.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

(cherry picked from commit 900c5952499fb233a9c0d2e6d0a5fde84a99cf72)

Conflicts:

	src/qemu/qemu_driver.c

            - no checkpoint APIs

            - no VIR_AUTOUNREF

            - ProcessAttach and XMLFromNative APIs were removed upstream

https://bugzilla.redhat.com/show_bug.cgi?id=1731783

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

Message-Id: <fb9a50220d762c69ee9d8b38c60a03b061b4127b.1565959866.git.jdenemar@redhat.com>

Reviewed-by: Ján Tomko <jtomko@redhat.com>

---

 src/qemu/qemu_domain.c           | 37 ++++++++++++++++++++------------

 src/qemu/qemu_domain.h           |  3 +++

 src/qemu/qemu_driver.c           | 22 ++++++++++++-------

 src/qemu/qemu_migration.c        |  6 +++---

 src/qemu/qemu_migration_cookie.c |  9 ++++++--

 src/qemu/qemu_process.c          | 11 +++++-----

 6 files changed, 56 insertions(+), 32 deletions(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c

index bf6013d42a..249ec4d259 100644

--- a/src/qemu/qemu_domain.c

+++ b/src/qemu/qemu_domain.c

@@ -7230,7 +7230,7 @@ qemuDomainDefCopy(virQEMUDriverPtr driver,

     virDomainDefPtr ret = NULL;

     char *xml;

-    if (!(xml = qemuDomainDefFormatXML(driver, src, flags)))

+    if (!(xml = qemuDomainDefFormatXML(driver, qemuCaps, src, flags)))

         return NULL;

     ret = qemuDomainDefFromXML(driver, qemuCaps, xml);

@@ -7242,6 +7242,7 @@ qemuDomainDefCopy(virQEMUDriverPtr driver,

 static int

 qemuDomainDefFormatBufInternal(virQEMUDriverPtr driver,

+                               virQEMUCapsPtr qemuCaps,

                                virDomainDefPtr def,

                                virCPUDefPtr origCPU,

                                unsigned int flags,

@@ -7250,7 +7251,7 @@ qemuDomainDefFormatBufInternal(virQEMUDriverPtr driver,

     int ret = -1;

     virDomainDefPtr copy = NULL;

     virCapsPtr caps = NULL;

-    virQEMUCapsPtr qemuCaps = NULL;

+    virQEMUCapsPtr qCaps = NULL;

     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))

         goto cleanup;

@@ -7258,7 +7259,7 @@ qemuDomainDefFormatBufInternal(virQEMUDriverPtr driver,

     if (!(flags & (VIR_DOMAIN_XML_UPDATE_CPU | VIR_DOMAIN_XML_MIGRATABLE)))

         goto format;

-    if (!(copy = virDomainDefCopy(def, caps, driver->xmlopt, NULL,

+    if (!(copy = virDomainDefCopy(def, caps, driver->xmlopt, qemuCaps,

                                   flags & VIR_DOMAIN_XML_MIGRATABLE)))

         goto cleanup;

@@ -7269,13 +7270,17 @@ qemuDomainDefFormatBufInternal(virQEMUDriverPtr driver,

         def->cpu &&

         (def->cpu->mode != VIR_CPU_MODE_CUSTOM ||

          def->cpu->model)) {

-        if (!(qemuCaps = virQEMUCapsCacheLookupCopy(driver->qemuCapsCache,

-                                                    def->emulator,

-                                                    def->os.machine)))

-            goto cleanup;

+        if (qemuCaps) {

+            qCaps = virObjectRef(qemuCaps);

+        } else {

+            if (!(qCaps = virQEMUCapsCacheLookupCopy(driver->qemuCapsCache,

+                                                     def->emulator,

+                                                     def->os.machine)))

+                goto cleanup;

+        }

         if (virCPUUpdate(def->os.arch, def->cpu,

-                         virQEMUCapsGetHostModel(qemuCaps, def->virtType,

+                         virQEMUCapsGetHostModel(qCaps, def->virtType,

                                                  VIR_QEMU_CAPS_HOST_CPU_MIGRATABLE)) < 0)

             goto cleanup;

     }

@@ -7424,30 +7429,32 @@ qemuDomainDefFormatBufInternal(virQEMUDriverPtr driver,

  cleanup:

     virDomainDefFree(copy);

     virObjectUnref(caps);

-    virObjectUnref(qemuCaps);

+    virObjectUnref(qCaps);

     return ret;

 }

 int

 qemuDomainDefFormatBuf(virQEMUDriverPtr driver,

+                       virQEMUCapsPtr qemuCaps,

                        virDomainDefPtr def,

                        unsigned int flags,

                        virBufferPtr buf)

 {

-    return qemuDomainDefFormatBufInternal(driver, def, NULL, flags, buf);

+    return qemuDomainDefFormatBufInternal(driver, qemuCaps, def, NULL, flags, buf);

 }

 static char *

 qemuDomainDefFormatXMLInternal(virQEMUDriverPtr driver,

+                               virQEMUCapsPtr qemuCaps,

                                virDomainDefPtr def,

                                virCPUDefPtr origCPU,

                                unsigned int flags)

 {

     virBuffer buf = VIR_BUFFER_INITIALIZER;

-    if (qemuDomainDefFormatBufInternal(driver, def, origCPU, flags, &buf) < 0)

+    if (qemuDomainDefFormatBufInternal(driver, qemuCaps, def, origCPU, flags, &buf) < 0)

         return NULL;

     return virBufferContentAndReset(&buf;;

@@ -7456,10 +7463,11 @@ qemuDomainDefFormatXMLInternal(virQEMUDriverPtr driver,

 char *

 qemuDomainDefFormatXML(virQEMUDriverPtr driver,

+                       virQEMUCapsPtr qemuCaps,

                        virDomainDefPtr def,

                        unsigned int flags)

 {

-    return qemuDomainDefFormatXMLInternal(driver, def, NULL, flags);

+    return qemuDomainDefFormatXMLInternal(driver, qemuCaps, def, NULL, flags);

 }

@@ -7478,11 +7486,12 @@ char *qemuDomainFormatXML(virQEMUDriverPtr driver,

         origCPU = priv->origCPU;

     }

-    return qemuDomainDefFormatXMLInternal(driver, def, origCPU, flags);

+    return qemuDomainDefFormatXMLInternal(driver, priv->qemuCaps, def, origCPU, flags);

 }

 char *

 qemuDomainDefFormatLive(virQEMUDriverPtr driver,

+                        virQEMUCapsPtr qemuCaps,

                         virDomainDefPtr def,

                         virCPUDefPtr origCPU,

                         bool inactive,

@@ -7495,7 +7504,7 @@ qemuDomainDefFormatLive(virQEMUDriverPtr driver,

     if (compatible)

         flags |= VIR_DOMAIN_XML_MIGRATABLE;

-    return qemuDomainDefFormatXMLInternal(driver, def, origCPU, flags);

+    return qemuDomainDefFormatXMLInternal(driver, qemuCaps, def, origCPU, flags);

 }

diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h

index 29283105cb..9546216f30 100644

--- a/src/qemu/qemu_domain.h

+++ b/src/qemu/qemu_domain.h

@@ -599,11 +599,13 @@ virDomainDefPtr qemuDomainDefCopy(virQEMUDriverPtr driver,

                                   unsigned int flags);

 int qemuDomainDefFormatBuf(virQEMUDriverPtr driver,

+                           virQEMUCapsPtr qemuCaps,

                            virDomainDefPtr vm,

                            unsigned int flags,

                            virBuffer *buf);

 char *qemuDomainDefFormatXML(virQEMUDriverPtr driver,

+                             virQEMUCapsPtr qemuCaps,

                              virDomainDefPtr vm,

                              unsigned int flags);

@@ -612,6 +614,7 @@ char *qemuDomainFormatXML(virQEMUDriverPtr driver,

                           unsigned int flags);

 char *qemuDomainDefFormatLive(virQEMUDriverPtr driver,

+                              virQEMUCapsPtr qemuCaps,

                               virDomainDefPtr def,

                               virCPUDefPtr origCPU,

                               bool inactive,

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c

index a486c66a5f..7d87215904 100644

--- a/src/qemu/qemu_driver.c

+++ b/src/qemu/qemu_driver.c

@@ -3316,9 +3316,10 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver,

             virDomainDefFree(def);

             goto endjob;

         }

-        xml = qemuDomainDefFormatLive(driver, def, NULL, true, true);

+        xml = qemuDomainDefFormatLive(driver, priv->qemuCaps, def, NULL, true, true);

     } else {

-        xml = qemuDomainDefFormatLive(driver, vm->def, priv->origCPU, true, true);

+        xml = qemuDomainDefFormatLive(driver, priv->qemuCaps, vm->def,

+                                      priv->origCPU, true, true);

     }

     if (!xml) {

         virReportError(VIR_ERR_OPERATION_FAILED,

@@ -6787,7 +6788,7 @@ qemuDomainSaveImageGetXMLDesc(virConnectPtr conn, const char *path,

     if (virDomainSaveImageGetXMLDescEnsureACL(conn, def) < 0)

         goto cleanup;

-    ret = qemuDomainDefFormatXML(driver, def, flags);

+    ret = qemuDomainDefFormatXML(driver, NULL, def, flags);

  cleanup:

     virQEMUSaveDataFree(data);

@@ -6840,7 +6841,7 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,

     VIR_FREE(data->xml);

-    if (!(data->xml = qemuDomainDefFormatXML(driver, newdef,

+    if (!(data->xml = qemuDomainDefFormatXML(driver, NULL, newdef,

                                              VIR_DOMAIN_XML_INACTIVE |

                                              VIR_DOMAIN_XML_SECURE |

                                              VIR_DOMAIN_XML_MIGRATABLE)))

@@ -6879,6 +6880,7 @@ qemuDomainManagedSaveGetXMLDesc(virDomainPtr dom, unsigned int flags)

     virDomainDefPtr def = NULL;

     int fd = -1;

     virQEMUSaveDataPtr data = NULL;

+    qemuDomainObjPrivatePtr priv;

     /* We only take subset of virDomainDefFormat flags.  */

     virCheckFlags(VIR_DOMAIN_XML_SECURE, NULL);

@@ -6886,6 +6888,8 @@ qemuDomainManagedSaveGetXMLDesc(virDomainPtr dom, unsigned int flags)

     if (!(vm = qemuDomObjFromDomain(dom)))

         return ret;

+    priv = vm->privateData;

+

     if (virDomainManagedSaveGetXMLDescEnsureACL(dom->conn, vm->def, flags) < 0)

         goto cleanup;

@@ -6902,7 +6906,7 @@ qemuDomainManagedSaveGetXMLDesc(virDomainPtr dom, unsigned int flags)

                                       false, NULL, false, false)) < 0)

         goto cleanup;

-    ret = qemuDomainDefFormatXML(driver, def, flags);

+    ret = qemuDomainDefFormatXML(driver, priv->qemuCaps, def, flags);

  cleanup:

     virQEMUSaveDataFree(data);

@@ -7097,7 +7101,7 @@ static char *qemuConnectDomainXMLFromNative(virConnectPtr conn,

     if (!def->name && VIR_STRDUP(def->name, "unnamed") < 0)

         goto cleanup;

-    xml = qemuDomainDefFormatXML(driver, def, VIR_DOMAIN_XML_INACTIVE);

+    xml = qemuDomainDefFormatXML(driver, NULL, def, VIR_DOMAIN_XML_INACTIVE);

  cleanup:

     virDomainDefFree(def);

@@ -15151,7 +15155,8 @@ qemuDomainSnapshotCreateActiveExternal(virQEMUDriverPtr driver,

                                                     "snapshot", false)) < 0)

             goto cleanup;

-        if (!(xml = qemuDomainDefFormatLive(driver, vm->def, priv->origCPU,

+        if (!(xml = qemuDomainDefFormatLive(driver, priv->qemuCaps,

+                                            vm->def, priv->origCPU,

                                             true, true)) ||

             !(snap->def->cookie = (virObjectPtr) qemuDomainSaveCookieNew(vm)))

             goto cleanup;

@@ -15395,7 +15400,8 @@ qemuDomainSnapshotCreateXML(virDomainPtr domain,

     } else {

         /* Easiest way to clone inactive portion of vm->def is via

          * conversion in and back out of xml.  */

-        if (!(xml = qemuDomainDefFormatLive(driver, vm->def, priv->origCPU,

+        if (!(xml = qemuDomainDefFormatLive(driver, priv->qemuCaps,

+                                            vm->def, priv->origCPU,

                                             true, true)) ||

             !(def->dom = virDomainDefParseString(xml, caps, driver->xmlopt, NULL,

                                                  VIR_DOMAIN_DEF_PARSE_INACTIVE |

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c

index 4af105b997..111038b971 100644

--- a/src/qemu/qemu_migration.c

+++ b/src/qemu/qemu_migration.c

@@ -2081,9 +2081,9 @@ qemuMigrationSrcBeginPhase(virQEMUDriverPtr driver,

         if (!qemuDomainCheckABIStability(driver, vm, def))

             goto cleanup;

-        rv = qemuDomainDefFormatLive(driver, def, NULL, false, true);

+        rv = qemuDomainDefFormatLive(driver, priv->qemuCaps, def, NULL, false, true);

     } else {

-        rv = qemuDomainDefFormatLive(driver, vm->def, priv->origCPU,

+        rv = qemuDomainDefFormatLive(driver, priv->qemuCaps, vm->def, priv->origCPU,

                                      false, true);

     }

@@ -2352,7 +2352,7 @@ qemuMigrationDstPrepareAny(virQEMUDriverPtr driver,

         char *xml;

         int hookret;

-        if (!(xml = qemuDomainDefFormatXML(driver, *def,

+        if (!(xml = qemuDomainDefFormatXML(driver, NULL, *def,

                                            VIR_DOMAIN_XML_SECURE |

                                            VIR_DOMAIN_XML_MIGRATABLE)))

             goto cleanup;

diff --git a/src/qemu/qemu_migration_cookie.c b/src/qemu/qemu_migration_cookie.c

index 60df449d53..901b1ae9ac 100644

--- a/src/qemu/qemu_migration_cookie.c

+++ b/src/qemu/qemu_migration_cookie.c

@@ -777,6 +777,7 @@ qemuMigrationCookieCapsXMLFormat(virBufferPtr buf,

 static int

 qemuMigrationCookieXMLFormat(virQEMUDriverPtr driver,

+                             virQEMUCapsPtr qemuCaps,

                              virBufferPtr buf,

                              qemuMigrationCookiePtr mig)

 {

@@ -818,6 +819,7 @@ qemuMigrationCookieXMLFormat(virQEMUDriverPtr driver,

     if ((mig->flags & QEMU_MIGRATION_COOKIE_PERSISTENT) &&

         mig->persistent) {

         if (qemuDomainDefFormatBuf(driver,

+                                   qemuCaps,

                                    mig->persistent,

                                    VIR_DOMAIN_XML_INACTIVE |

                                    VIR_DOMAIN_XML_SECURE |

@@ -869,11 +871,12 @@ qemuMigrationCookieXMLFormat(virQEMUDriverPtr driver,

 static char *

 qemuMigrationCookieXMLFormatStr(virQEMUDriverPtr driver,

+                                virQEMUCapsPtr qemuCaps,

                                 qemuMigrationCookiePtr mig)

 {

     virBuffer buf = VIR_BUFFER_INITIALIZER;

-    if (qemuMigrationCookieXMLFormat(driver, &buf, mig) < 0) {

+    if (qemuMigrationCookieXMLFormat(driver, qemuCaps, &buf, mig) < 0) {

         virBufferFreeAndReset(&buf;;

         return NULL;

     }

@@ -1416,6 +1419,8 @@ qemuMigrationBakeCookie(qemuMigrationCookiePtr mig,

                         int *cookieoutlen,

                         unsigned int flags)

 {

+    qemuDomainObjPrivatePtr priv = dom->privateData;

+

     if (!cookieout || !cookieoutlen)

         return 0;

@@ -1459,7 +1464,7 @@ qemuMigrationBakeCookie(qemuMigrationCookiePtr mig,

         qemuMigrationCookieAddCaps(mig, dom, party) < 0)

         return -1;

-    if (!(*cookieout = qemuMigrationCookieXMLFormatStr(driver, mig)))

+    if (!(*cookieout = qemuMigrationCookieXMLFormatStr(driver, priv->qemuCaps, mig)))

         return -1;

     *cookieoutlen = strlen(*cookieout) + 1;

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c

index 9e6e6528e2..34686b4d92 100644

--- a/src/qemu/qemu_process.c

+++ b/src/qemu/qemu_process.c

@@ -4434,13 +4434,14 @@ qemuProcessStartHook(virQEMUDriverPtr driver,

                      virHookQemuOpType op,

                      virHookSubopType subop)

 {

+    qemuDomainObjPrivatePtr priv = vm->privateData;

     char *xml;

     int ret;

     if (!virHookPresent(VIR_HOOK_DRIVER_QEMU))

         return 0;

-    if (!(xml = qemuDomainDefFormatXML(driver, vm->def, 0)))

+    if (!(xml = qemuDomainDefFormatXML(driver, priv->qemuCaps, vm->def, 0)))

         return -1;

     ret = virHookCall(VIR_HOOK_DRIVER_QEMU, vm->def->name, op, subop,

@@ -7091,7 +7092,7 @@ void qemuProcessStop(virQEMUDriverPtr driver,

     /* now that we know it's stopped call the hook if present */

     if (virHookPresent(VIR_HOOK_DRIVER_QEMU)) {

-        char *xml = qemuDomainDefFormatXML(driver, vm->def, 0);

+        char *xml = qemuDomainDefFormatXML(driver, NULL, vm->def, 0);

         /* we can't stop the operation even if the script raised an error */

         ignore_value(virHookCall(VIR_HOOK_DRIVER_QEMU, vm->def->name,

@@ -7249,7 +7250,7 @@ void qemuProcessStop(virQEMUDriverPtr driver,

     /* The "release" hook cleans up additional resources */

     if (virHookPresent(VIR_HOOK_DRIVER_QEMU)) {

-        char *xml = qemuDomainDefFormatXML(driver, vm->def, 0);

+        char *xml = qemuDomainDefFormatXML(driver, NULL, vm->def, 0);

         /* we can't stop the operation even if the script raised an error */

         virHookCall(VIR_HOOK_DRIVER_QEMU, vm->def->name,

@@ -7473,7 +7474,7 @@ int qemuProcessAttach(virConnectPtr conn ATTRIBUTE_UNUSED,

     /* Run an hook to allow admins to do some magic */

     if (virHookPresent(VIR_HOOK_DRIVER_QEMU)) {

-        char *xml = qemuDomainDefFormatXML(driver, vm->def, 0);

+        char *xml = qemuDomainDefFormatXML(driver, priv->qemuCaps, vm->def, 0);

         int hookret;

         hookret = virHookCall(VIR_HOOK_DRIVER_QEMU, vm->def->name,

@@ -7934,7 +7935,7 @@ qemuProcessReconnect(void *opaque)

     /* Run an hook to allow admins to do some magic */

     if (virHookPresent(VIR_HOOK_DRIVER_QEMU)) {

-        char *xml = qemuDomainDefFormatXML(driver, obj->def, 0);

+        char *xml = qemuDomainDefFormatXML(driver, priv->qemuCaps, obj->def, 0);

         int hookret;

         hookret = virHookCall(VIR_HOOK_DRIVER_QEMU, obj->def->name,

-- 

2.22.1