Thanks for your replay.
I've augmented debug level, run virsh domxml-from-native xen-xm
backupsrv.cfg and this is the error:
virsh: malloc.c:3097: sYSMALLOc: Assertion `(old_top == (((mbinptr)
(((char *) &((av)->bins[((1) - 1) * 2])) - __builtin_offsetof (struct
malloc_chunk, fd)))) && old_size == 0) || ((unsigned long) (old_size)
= (unsigned long)((((__builtin_offsetof (struct malloc_chunk,
fd_nextsize))+((2 * (sizeof(size_t))) - 1)) & ~((2 * (sizeof(size_t)))
- 1))) && ((old_top)->size & 0x1) && ((unsigned long)old_end &
pagemask) == 0)' failed.