panic in daprobedone: Unholding 4 with cnt = 0

[Warner Losh]

On Sat, Feb 17, 2018 at 8:04 AM, Hans Petter Selasky <hps at selasky.org>
wrote:

> On 02/17/18 15:47, Warner Losh wrote:
>
>> That's interesting. What did you do to get there? There's some code path
>> that's unholding the periph without first holding it. I've been trying to
>> find a scenario.
>>
>>
> I just booted into single user mode with a multi-card USB reader attached.
> Seems like some kind of race. Doesn't happen during normal boot.


I've done that with my systems here...

If you can reliably reproduce it, booting a kernel with 'options
DA_TRACK_REFS=2' in the kernel config and send me the output?

Warner