RE: [PATCH 1/1] Drivers: hv: util: on deinit, don't wait the release event, if we shouldn't

[Dexuan Cui]

> From: kys@xxxxxxxxxxxxxxxxxxxxxx [mailto:kys@xxxxxxxxxxxxxxxxxxxxxx]
> Sent: Tuesday, February 28, 2017 07:18
> To: gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> ...
> From: Dexuan Cui <decui@xxxxxxxxxxxxx>
> 
> If the daemon is NOT running at all, when we disable the util device from
> Hyper-V Manager (or sometimes the host can rescind a util device and then
> re-offer it), we'll hang in util_remove -> hv_kvp_deinit ->
> wait_for_completion(&release_event), because this code path doesn't run:
> hvt_op_release -> ... -> kvp_on_reset -> complete(&release_event).
> 
> Due to this, we even can't reboot the VM properly.
> 
> The patch tracks if the dev file is opened or not, and we only need to
> wait if it's opened.
> 
> Fixes: 5a66fecbf6aa ("Drivers: hv: util: kvp: Fix a rescind processing issue")
> 
> Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
> ...

Please ignore this patch, since Vitaly posted a better fix instead.

Thanks,
-- Dexuan