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From:   Dexuan Cui <decui@microsoft.com>
To:     Wei Liu <wei.liu@kernel.org>
CC:     Michael Kelley <mikelley@microsoft.com>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
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        "marcelo.cerri@canonical.com" <marcelo.cerri@canonical.com>
Subject: RE: [PATCH] Drivers: hv: vmbus: Add /sys/bus/vmbus/supported_features
Thread-Topic: [PATCH] Drivers: hv: vmbus: Add
 /sys/bus/vmbus/supported_features
Thread-Index: AQHW42JoMmd2hzIYf0moXWkZCcjfFaoZnG+AgAEtXICAAEIz8A==
Date:   Wed, 6 Jan 2021 20:48:30 +0000
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> From: Wei Liu <wei.liu@kernel.org>
> Sent: Wednesday, January 6, 2021 8:24 AM
> To: Dexuan Cui <decui@microsoft.com>
> >
> > That said, I don't know if there is any hard rule in regard of
> > the timing here. If there is, then v5.12 is OK to me. :-)
> >
>=20
> By the time you posted this (Dec 22), 5.11 was already more or less
> "frozen". Linus wanted -next patches to be merged before Christmas.

Got it. Thanks for the explanation!

> The way I see it this is a new sysfs interface so I think this is
> something new, which is for 5.12.

Ok.=20

> Do you think this should be considered a bug fix?
>=20
> Wei.

Then let's not consider it for v5.11. For now I think the userspace
tool/daemon can check 'dmesg' for the existence of ACPI S4 state
as a workaround. This is not ideal, but it should work reasonably
well, assuming the tool/daemon runs early enough, so the kernel
msg buffer is not yet filled up and overwritten. :-)

Thanks,
-- Dexuan