[SPDK] ioat: "could not start channel" after abnormal exit

Hi SPDK team,

I'm using SPDK (v20-01-pre) to evaluate I/OAT performance. There are some bugs in my benchmark program, 
but after I use ctrl+c to quit my program and restart it again, some error messages appeared:

ioat.c: 480:ioat_channel_start: *ERROR*: could not start channel: status = 0x3
 error = 0
ioat.c: 547:ioat_enum_cb: *ERROR*: ioat_attach() failed
EAL: Requested device 0000:00:04.0 cannot be used
ioat.c: 480:ioat_channel_start: *ERROR*: could not start channel: status = 0x3
 error = 0
ioat.c: 547:ioat_enum_cb: *ERROR*: ioat_attach() failed
EAL: Requested device 0000:00:04.1 cannot be used
ioat.c: 480:ioat_channel_start: *ERROR*: could not start channel: status = 0x3
 error = 0
ioat.c: 547:ioat_enum_cb: *ERROR*: ioat_attach() failed
EAL: Requested device 0000:00:04.2 cannot be used
ioat.c: 480:ioat_channel_start: *ERROR*: could not start channel: status = 0x3
 error = 0
ioat.c: 547:ioat_enum_cb: *ERROR*: ioat_attach() failed
EAL: Requested device 0000:00:04.3 cannot be used
ioat.c: 480:ioat_channel_start: *ERROR*: could not start channel: status = 0x3
 error = 0
ioat.c: 547:ioat_enum_cb: *ERROR*: ioat_attach() failed
EAL: Requested device 0000:40:04.0 cannot be used
ioat.c: 480:ioat_channel_start: *ERROR*: could not start channel: status = 0x3
 error = 0
ioat.c: 547:ioat_enum_cb: *ERROR*: ioat_attach() failed
EAL: Requested device 0000:40:04.1 cannot be used
ioat.c: 480:ioat_channel_start: *ERROR*: could not start channel: status = 0x3
 error = 0

I checked the code in lib/ioat/ioat.c, it seems is_ioat_idle always returns negative results.
What should I do to deal with this problem without rebooting my server? Or, at least,
how to prevent it?

Thanks,
Jiahao Li