On 6/21/22 3:55 AM, Michal Prívozník wrote:
> On 6/17/22 23:29, Cole Robinson wrote:
>> When domain startup fails, domain cleanup calls
>> libxlNetworkUnwindDevices, which calls virGetConnectNetwork, which
>> is a top level API entry point, which resets the initial saved error,
>> leading to clients seeing:
>>
>> error: An error occurred, but the cause is unknown
>>
>> This preserves the error from before virGetConnectNetwork is called.
>>
>> Signed-off-by: Cole Robinson <crobinso@xxxxxxxxxx>
>> ---
>> src/libxl/libxl_domain.c | 7 ++++++-
>> 1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/src/libxl/libxl_domain.c b/src/libxl/libxl_domain.c
>> index 17b347de4e..bda110e9e6 100644
>> --- a/src/libxl/libxl_domain.c
>> +++ b/src/libxl/libxl_domain.c
>> @@ -830,12 +830,17 @@ libxlNetworkUnwindDevices(virDomainDef *def)
>> /* cleanup actual device */
>> virDomainNetRemoveHostdev(def, net);
>> if (net->type == VIR_DOMAIN_NET_TYPE_NETWORK) {
>> - g_autoptr(virConnect) conn = virGetConnectNetwork();
>> + g_autoptr(virConnect) conn = NULL;
>> + virErrorPtr save_err;
>> +
>> + virErrorPreserveLast(&save_err);
>> + conn = virGetConnectNetwork();
>>
>> if (conn)
>> virDomainNetReleaseActualDevice(conn, def, net);
>> else
>> VIR_WARN("Unable to release network device '%s'", NULLSTR(net->ifname));
>> + virErrorRestore(&save_err);
>> }
>> }
>> }
>
> This fixes this particular function. I wonder whether we should mimic
> what QEMU driver does and wrap whole qemuProcessShutdown(), I mean
> libxlDomainCleanup() in virErrorPreserveLast(). Something like this:
>
> diff --git i/src/libxl/libxl_domain.c w/src/libxl/libxl_domain.c
> index bda110e9e6..8e8ddd284a 100644
> --- i/src/libxl/libxl_domain.c
> +++ w/src/libxl/libxl_domain.c
> @@ -908,10 +908,13 @@ libxlDomainCleanup(libxlDriverPrivate *driver,
> virHostdevManager *hostdev_mgr = driver->hostdevMgr;
> unsigned int hostdev_flags = VIR_HOSTDEV_SP_PCI;
> size_t i;
> + virErrorPtr save_err;
>
> VIR_DEBUG("Cleaning up domain with id '%d' and name '%s'",
> vm->def->id, vm->def->name);
>
> + virErrorPreserveLast(&save_err);
> +
> hostdev_flags |= VIR_HOSTDEV_SP_USB;
>
> /* Call hook with stopped operation. Ignore error and continue with cleanup */
> @@ -984,6 +987,7 @@ libxlDomainCleanup(libxlDriverPrivate *driver,
> VIR_HOOK_SUBOP_END, NULL));
>
> virDomainObjRemoveTransientDef(vm);
> + virErrorRestore(&save_err);
> }
>
> /*
> @@ -1245,6 +1249,7 @@ libxlDomainStartPrepare(libxlDriverPrivate *driver,
> {
> virHostdevManager *hostdev_mgr = driver->hostdevMgr;
> unsigned int hostdev_flags = VIR_HOSTDEV_SP_PCI | VIR_HOSTDEV_SP_USB;
> + virErrorPtr save_err;
>
> if (virDomainObjSetDefTransient(driver->xmlopt, vm, NULL) < 0)
> return -1;
> @@ -1272,10 +1277,12 @@ libxlDomainStartPrepare(libxlDriverPrivate *driver,
> return 0;
>
> error:
> + virErrorPreserveLast(&save_err);
> libxlNetworkUnwindDevices(vm->def);
> virHostdevReAttachDomainDevices(hostdev_mgr, LIBXL_DRIVER_INTERNAL_NAME,
> vm->def, hostdev_flags);
> virDomainObjRemoveTransientDef(vm);
> + virErrorRestore(&save_err);
> return -1;
> }
>
>
> If this works, replace your patch with this diff, apply my:
>
> Reviewed-by: Michal Privoznik <mprivozn@xxxxxxxxxx>
Thanks, I made that change and pushed now
- Cole
