[SPDK] performing i/o to a disk while removing cause the cpu to stuck

Hi,
We are using SPDK 19.07, nvme device, vfio driver.
We got into a situation that removing disk, while performing I/O to it,
stall the CPU in the function spdk_mmio_write_4, when accessing the PCI
register, in the line  *addr = val

any idea ?

Thanks,
Avner