Re: [PATCH v2] migration/colo: Fix bdrv_graph_rdlock_main_loop: Assertion `!qemu_in_coroutine()' failed.

[Fabiano Rosas]

Li Zhijian via <qemu-devel@nongnu.org> writes:

> bdrv_activate_all() should not be called from the coroutine context, move
> it to the QEMU thread colo_process_incoming_thread() with the bql_lock
> protected.
>
> The backtrace is as follows:
>  #4  0x0000561af7948362 in bdrv_graph_rdlock_main_loop () at 
> ../block/graph-lock.c:260
>  #5  0x0000561af7907a68 in graph_lockable_auto_lock_mainloop 
> (x=0x7fd29810be7b) at /patch/to/qemu/include/block/graph-lock.h:259
>  #6  0x0000561af79167d1 in bdrv_activate_all (errp=0x7fd29810bed0) at 
> ../block.c:6906
>  #7  0x0000561af762b4af in colo_incoming_co () at ../migration/colo.c:935
>  #8  0x0000561af7607e57 in process_incoming_migration_co (opaque=0x0) at 
> ../migration/migration.c:793
>  #9  0x0000561af7adbeeb in coroutine_trampoline (i0=-106876144, i1=22042) at 
> ../util/coroutine-ucontext.c:175
>  #10 0x00007fd2a5cf21c0 in  () at /lib64/libc.so.6
>
> CC: Fabiano Rosas <farosas@suse.de>
> Closes: https://gitlab.com/qemu-project/qemu/-/issues/2277
> Fixes: 2b3912f135 ("block: Mark bdrv_first_blk() and bdrv_is_root_node() 
> GRAPH_RDLOCK")
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>

Reviewed-by: Fabiano Rosas <farosas@suse.de>