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Subject: RE: [EXT] [PATCH v1 5/5] scsi: ufs: Complete pending requests in host
 reset and restore path
Thread-Topic: [EXT] [PATCH v1 5/5] scsi: ufs: Complete pending requests in
 host reset and restore path
Thread-Index: AQHVlgzPbiOALT34b0a4wX/4UETvQqeJrjpQ
Date:   Wed, 13 Nov 2019 22:04:03 +0000
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>=20
> In UFS host reset and restore path, before probe, we stop and start the h=
ost
> controller once. After host controller is stopped, the pending requests, =
if any,
> are cleared from the doorbell, but no completion IRQ would be raised due =
to the
> hba is stopped.
> These pending requests shall be completed along with the first NOP_OUT
> command(as it is the first command which can raise a transfer completion
> IRQ) sent during probe.

Hi, Can
I am not sure for this point, because there is HW/SW device reset before or=
 after host reset/restore.
Device HW/SW reset also will clear the pended tasks in device side. That wi=
ll be better.
I think Qcom platform already enabled HW reset.

//Bean

> Since the OCSs of these pending requests are not SUCCESS(because they are=
 not
> yet literally finished), their UPIUs shall be dumped. When there are mult=
iple
> pending requests, the UPIU dump can be overwhelming and may lead to stabi=
lity
> issues because it is in atomic context.
> Therefore, before probe, complete these pending requests right after host
> controller is stopped.