> The following steps will cause qemu assertion failure:
> - pause vm
> - save memory snapshot into local file through fd migration
> - do the above operation again will cause qemu assertion failure
>
> 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_recurse(), and during the second migration the
> bdrv_inactivate_recurse assert that the bs->open_flags is already
> BDRV_O_INACTIVE
> enabled which cause crash.
>
> This patch just make the bdrv_inactivate_all() to don't inactivate the bs if
> it is
> already inactive
>
> Signed-off-by: Tuguoyi <tu.gu...@h3c.com>
> ---
> block.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/block.c b/block.c
> index f1cedac..02361e1 100644
> --- a/block.c
> +++ b/block.c
> @@ -5938,6 +5938,11 @@ static int bdrv_inactivate_recurse(BlockDriverState
> *bs)
> return 0;
> }
>
> +static bool bdrv_is_inactive(BlockDriverState *bs)
> +{
> + return bs->open_flags & BDRV_O_INACTIVE;
> +}
> +
> int bdrv_inactivate_all(void)
> {
> BlockDriverState *bs = NULL;
> @@ -5958,7 +5963,7 @@ int bdrv_inactivate_all(void)
> /* Nodes with BDS parents are covered by recursion from the last
> * parent that gets inactivated. Don't inactivate them a second
> * time if that has already happened. */
> - if (bdrv_has_bds_parent(bs, false)) {
> + if (bdrv_has_bds_parent(bs, false) || bdrv_is_inactive(bs)) {
> continue;
> }
> ret = bdrv_inactivate_recurse(bs);
> --
> 2.7.4
Ping
