On Fri, 02/12 09:39, Denis V. Lunev wrote:
> There is a possibility to hit an assert in qcow2_get_specific_info that
> s->qcow_version is undefined. This happens when VM in starting from
> suspended state, i.e. it processes incoming migration, and in the same
> time 'info block' is called.
>
> The problem is that qcow2_invalidate_cache() closes the image and
> memset()s BDRVQcowState in the middle.
>
> The patch moves processing of bdrv_invalidate_cache_all out of
> coroutine context for standard migration to avoid that.
>
> Signed-off-by: Denis V. Lunev <d...@openvz.org>
> CC: Paolo Bonzini <pbonz...@redhat.com>
> CC: Juan Quintela <quint...@redhat.com>
> CC: Amit Shah <amit.s...@redhat.com>
> ---
> migration/migration.c | 89
> ++++++++++++++++++++++++++++-----------------------
> 1 file changed, 49 insertions(+), 40 deletions(-)
>
> diff --git a/migration/migration.c b/migration/migration.c
> index a64cfcd..1f8535e 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -323,13 +323,59 @@ void qemu_start_incoming_migration(const char *uri,
> Error **errp)
> }
> }
>
> +static void process_incoming_migration_bh(void *opaque)
> +{
> + Error *local_err = NULL;
> + MigrationIncomingState *mis = opaque;
> +
> + /* Make sure all file formats flush their mutable metadata */
> + bdrv_invalidate_cache_all(&local_err);
> + if (local_err) {
> + migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
> + MIGRATION_STATUS_FAILED);
> + error_report_err(local_err);
> + migrate_decompress_threads_join();
> + exit(EXIT_FAILURE);
> + }
> +
> + /*
> + * This must happen after all error conditions are dealt with and
> + * we're sure the VM is going to be running on this host.
> + */
> + qemu_announce_self();
> +
> + /* If global state section was not received or we are in running
> + state, we need to obey autostart. Any other state is set with
> + runstate_set. */
> +
> + if (!global_state_received() ||
> + global_state_get_runstate() == RUN_STATE_RUNNING) {
> + if (autostart) {
> + vm_start();
> + } else {
> + runstate_set(RUN_STATE_PAUSED);
> + }
> + } else {
> + runstate_set(global_state_get_runstate());
> + }
> + migrate_decompress_threads_join();
> + /*
> + * This must happen after any state changes since as soon as an external
> + * observer sees this event they might start to prod at the VM assuming
> + * it's ready to use.
> + */
> + migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
> + MIGRATION_STATUS_COMPLETED);
> + migration_incoming_state_destroy();
> +}
> +
> static void process_incoming_migration_co(void *opaque)
> {
> QEMUFile *f = opaque;
> - Error *local_err = NULL;
> MigrationIncomingState *mis;
> PostcopyState ps;
> int ret;
> + QEMUBH *bh;
>
> mis = migration_incoming_state_new(f);
> postcopy_state_set(POSTCOPY_INCOMING_NONE);
> @@ -369,45 +415,8 @@ static void process_incoming_migration_co(void *opaque)
> exit(EXIT_FAILURE);
> }
>
> - /* Make sure all file formats flush their mutable metadata */
> - bdrv_invalidate_cache_all(&local_err);
> - if (local_err) {
> - migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
> - MIGRATION_STATUS_FAILED);
> - error_report_err(local_err);
> - migrate_decompress_threads_join();
> - exit(EXIT_FAILURE);
> - }
> -
> - /*
> - * This must happen after all error conditions are dealt with and
> - * we're sure the VM is going to be running on this host.
> - */
> - qemu_announce_self();
> -
> - /* If global state section was not received or we are in running
> - state, we need to obey autostart. Any other state is set with
> - runstate_set. */
> -
> - if (!global_state_received() ||
> - global_state_get_runstate() == RUN_STATE_RUNNING) {
> - if (autostart) {
> - vm_start();
> - } else {
> - runstate_set(RUN_STATE_PAUSED);
> - }
> - } else {
> - runstate_set(global_state_get_runstate());
> - }
> - migrate_decompress_threads_join();
> - /*
> - * This must happen after any state changes since as soon as an external
> - * observer sees this event they might start to prod at the VM assuming
> - * it's ready to use.
> - */
> - migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
> - MIGRATION_STATUS_COMPLETED);
> - migration_incoming_state_destroy();
> + bh = qemu_bh_new(process_incoming_migration_bh, mis);
Don't you need to call qemu_bh_delete somewhere? (Also applies to the other
patch)
Fam
> + qemu_bh_schedule(bh);
> }
>
> void process_incoming_migration(QEMUFile *f)
> --
> 2.1.4
>
>
