Roman Khapov <rkha...@yandex-team.ru> writes:
Hi Roman,
> This is resending of series 20240215082659.1378342-1-rkha...@yandex-team.ru,
> where patch subjects numbers were broken in patch 2/2.
>
> Sometimes, when migration fails, it is hard to find out
> the cause of the problems: you have to grep qemu logs.
> At the same time, there is MIGRATION event, which looks like
> suitable place to hold such error descriptions.
query-migrate after the event is received should be enough for giving
you the failure reason. We have that in error-desc. See commit
c94143e587 ("migration: Display error in query-migrate irrelevant of
status").
>
> To handle situation like this (maybe one day it will be useful
> for other MIGRATION statuses to have additional 'reason' strings),
I find it unlikely. There's no "reason" for making progress except
that's how things work. Only the exceptional (i.e. failure) statuses
would have a reason. Today that's FAILED only, maybe also
POSTCOPY_PAUSED.
> the general optional field 'reason' can be added.
>
> The series proposes next changes:
>
> 1. Adding optional 'reason' field of type str into
> qapi/migration.json MIGRATION event
>
> 2. Passing some error description as reason for every place, which
> sets migration state to MIGRATION_STATUS_FAILED
>
> After the series, MIGRATION event will looks like this:
> {"execute": "qmp_capabilities"}
> {"return": {}}
> {"event": "MIGRATION", "data": {"status": "setup"}}
> {"event": "MIGRATION", "data": {"status": "failed", "reason": "Failed to
> connect to '/tmp/sock.sock': No such file or directory"}}
>
> Roman Khapov (2):
> qapi/migration.json: add reason to MIGRATION event
> migration: add error reason for failed MIGRATION events
>
> migration/colo.c | 6 +-
> migration/migration.c | 128 ++++++++++++++++++++++++++++--------------
> migration/migration.h | 5 +-
> migration/multifd.c | 10 ++--
> migration/savevm.c | 24 ++++----
> qapi/migration.json | 3 +-
> 6 files changed, 112 insertions(+), 64 deletions(-)
Please remember to run make check:
380/383 qemu:qtest+qtest-x86_64 / qtest-x86_64/migration-test ERROR
104.77s killed by signal 6 SIGABRT
―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――
stderr: Broken pipe ../tests/qtest/libqtest.c:204: kill_qemu() detected
QEMU death from signal 11 (Segmentation fault) (core dumped)
Most likely one of the new error_setg has broken postcopy recovery. Some
of those paths are not intended to trigger cleanup.
