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From:   Dexuan Cui <decui@microsoft.com>
To:     Wei Liu <wei.liu@kernel.org>
CC:     Tianyu Lan <ltykernel@gmail.com>,
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Subject: RE: [PATCH V5 2/8] x86/hyperv: Set Virtual Trust Level in VMBus init
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Thread-Topic: [PATCH V5 2/8] x86/hyperv: Set Virtual Trust Level in VMBus init
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Thread-Index: AQHZy6RY7nYR/0UDx067fCeHwlC69q/kIcWggAF4xYCAAA9Y4A==
Date:   Fri, 11 Aug 2023 22:16:19 +0000
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> From: Wei Liu <wei.liu@kernel.org>
> Sent: Friday, August 11, 2023 2:15 PM
> To: Dexuan Cui <decui@microsoft.com>
> > [...]
> > > +	local_irq_save(flags);
> > > +	input =3D *this_cpu_ptr(hyperv_pcpu_input_arg);
> > > +	output =3D (struct hv_get_vp_registers_output *)input;
> > > +	if (!input) {
> > > +		local_irq_restore(flags);
> > > +		goto done;
> >
> > Here the uninitialized 'ret' is returned.
> >
> > If we move the "done:" label one line earlier, we won't need the
> > the above " local_irq_restore(flags);"
> > Maybe we should add a WARN_ON_ONCE(1) before "goto done"?
>=20
> Out of interest why will input be NULL here?
>=20
> Thanks,
> Wei.

I don't think 'input' could be NULL here.
IMO we can use it without checking against NULL.