Ping. It seems no one handle this patch.
> -----Original Message----- > From: Pankaj Gupta [mailto:pankaj.gupta.li...@gmail.com] > Sent: Wednesday, December 09, 2020 10:21 PM > To: tuguoyi (Cloud) <tu.gu...@h3c.com> > Cc: Juan Quintela <quint...@redhat.com>; Dr. David Alan Gilbert > <dgilb...@redhat.com>; vsement...@virtuozzo.com; > qemu-devel@nongnu.org; Li Zhang <li.zh...@cloud.ionos.com> > Subject: Re: [PATCH v3] migration: Don't allow migration if vm is in > POSTMIGRATE > > > The following steps will cause qemu assertion failure: > > - pause vm by executing 'virsh suspend' > > - create external snapshot of memory and disk using 'virsh > snapshot-create-as' > > - doing the above operation again will cause qemu crash > > > > The backtrace looks like: > > #0 0x00007fbf958c5c37 in raise () from /lib/x86_64-linux-gnu/libc.so.6 > > #1 0x00007fbf958c9028 in abort () from /lib/x86_64-linux-gnu/libc.so.6 > > #2 0x00007fbf958bebf6 in ?? () from /lib/x86_64-linux-gnu/libc.so.6 > > #3 0x00007fbf958beca2 in __assert_fail () from > /lib/x86_64-linux-gnu/libc.so.6 > > #4 0x000055ca8decd39d in bdrv_inactivate_recurse (bs=0x55ca90c80400) > at /build/qemu-5.0/block.c:5724 > > #5 0x000055ca8dece967 in bdrv_inactivate_all () at > /build//qemu-5.0/block.c:5792 > > #6 0x000055ca8de5539d in > qemu_savevm_state_complete_precopy_non_iterable (inactivate_disks=true, > in_postcopy=false, f=0x55ca907044b0) > > at /build/qemu-5.0/migration/savevm.c:1401 > > #7 qemu_savevm_state_complete_precopy (f=0x55ca907044b0, > iterable_only=iterable_only@entry=false, > inactivate_disks=inactivate_disks@entry=true) > > at /build/qemu-5.0/migration/savevm.c:1453 > > #8 0x000055ca8de4f581 in migration_completion (s=0x55ca8f64d9f0) at > /build/qemu-5.0/migration/migration.c:2941 > > #9 migration_iteration_run (s=0x55ca8f64d9f0) at > /build/qemu-5.0/migration/migration.c:3295 > > #10 migration_thread (opaque=opaque@entry=0x55ca8f64d9f0) at > /build/qemu-5.0/migration/migration.c:3459 > > #11 0x000055ca8dfc6716 in qemu_thread_start (args=<optimized out>) at > /build/qemu-5.0/util/qemu-thread-posix.c:519 > > #12 0x00007fbf95c5f184 in start_thread () from > /lib/x86_64-linux-gnu/libpthread.so.0 > > #13 0x00007fbf9598cbed in clone () from /lib/x86_64-linux-gnu/libc.so.6 > > > > When the first migration completes, bs->open_flags will set > BDRV_O_INACTIVE > > flag by bdrv_inactivate_all(), and during the second migration the > > bdrv_inactivate_recurse assert that the bs->open_flags is already > > BDRV_O_INACTIVE enabled which cause crash. > > > > As Vladimir suggested, this patch makes migrate_prepare check the state of > vm and > > return error if it is in RUN_STATE_POSTMIGRATE state. > > > > Signed-off-by: Tuguoyi <tu.gu...@h3c.com> > Similar issue is reported by Li Zhang(+CC) with almost same patch[3] > to fix this. > > Reported-by: Li Zhang <li.zh...@cloud.ionos.com> > Reviewed-by: Pankaj Gupta <pankaj.gu...@cloud.ionos.com> > > [3] https://marc.info/?l=qemu-devel&m=160749859831357&w=2 > > --- > > migration/migration.c | 6 ++++++ > > 1 file changed, 6 insertions(+) > > > > diff --git a/migration/migration.c b/migration/migration.c > > index 87a9b59..5e33962 100644 > > --- a/migration/migration.c > > +++ b/migration/migration.c > > @@ -2115,6 +2115,12 @@ static bool migrate_prepare(MigrationState *s, > bool blk, bool blk_inc, > > return false; > > } > > > > + if (runstate_check(RUN_STATE_POSTMIGRATE)) { > > + error_setg(errp, "Can't migrate the vm that was paused due to " > > + "previous migration"); > > + return false; > > + } > > + > > if (migration_is_blocked(errp)) { > > return false; > > } > > -- > > 2.7.4 > > > > [Patch v2]: > https://lists.gnu.org/archive/html/qemu-devel/2020-12/msg01318.html > > [Patch v1]: > https://lists.gnu.org/archive/html/qemu-devel/2020-11/msg05950.html
