This is an issue that's bugging me for a long time. I don't know exactly when and who is to blame but on daemon reconnect we lose qemu's port allocator internal state. That's okay as we should be able to rebuild it later. However, now I'm seeing port allocator biding successfully to ports that are already taken by qemu (either VNC or Spice). Thus any attempt to start another domain after daemon is restarted fails because libvirt instructs qemu to take port 5900 which is already taken. Now, I don't want to mask the real problem, but one can advocate that we should be marking graphics ports as already in use on qemuProcessReconnect anyway, because we already know that they are taken. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- src/qemu/qemu_process.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index d3155e4e7..053aba1a6 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -4035,7 +4035,8 @@ qemuProcessStartHook(virQEMUDriverPtr driver, static int qemuProcessGraphicsReservePorts(virQEMUDriverPtr driver, - virDomainGraphicsDefPtr graphics) + virDomainGraphicsDefPtr graphics, + bool reconnect) { virDomainGraphicsListenDefPtr glisten; @@ -4050,7 +4051,8 @@ qemuProcessGraphicsReservePorts(virQEMUDriverPtr driver, switch (graphics->type) { case VIR_DOMAIN_GRAPHICS_TYPE_VNC: - if (!graphics->data.vnc.autoport) { + if (!graphics->data.vnc.autoport || + reconnect) { if (virPortAllocatorSetUsed(driver->remotePorts, graphics->data.vnc.port, true) < 0) @@ -4065,7 +4067,7 @@ qemuProcessGraphicsReservePorts(virQEMUDriverPtr driver, break; case VIR_DOMAIN_GRAPHICS_TYPE_SPICE: - if (graphics->data.spice.autoport) + if (graphics->data.spice.autoport && !reconnect) return 0; if (graphics->data.spice.port > 0) { @@ -4269,7 +4271,7 @@ qemuProcessSetupGraphics(virQEMUDriverPtr driver, for (i = 0; i < vm->def->ngraphics; i++) { graphics = vm->def->graphics[i]; - if (qemuProcessGraphicsReservePorts(driver, graphics) < 0) + if (qemuProcessGraphicsReservePorts(driver, graphics, false) < 0) goto cleanup; } } @@ -6881,6 +6883,13 @@ qemuProcessReconnect(void *opaque) goto error; } + for (i = 0; i < obj->def->ngraphics; i++) { + if (qemuProcessGraphicsReservePorts(driver, + obj->def->graphics[i], + true) < 0) + goto error; + } + if (qemuProcessUpdateState(driver, obj) < 0) goto error; -- 2.13.5