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Subject: RE: [PATCH v8 1/6] arm64: hyperv: Add Hyper-V hypercall and register
 access utilities
Thread-Topic: [PATCH v8 1/6] arm64: hyperv: Add Hyper-V hypercall and register
 access utilities
Thread-Index: AQHXDwVm7IanFUbz6UeLdWLFekPIfapxZzMggAEuN+A=
Date:   Wed, 3 Mar 2021 18:28:16 +0000
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> > +
> > +	/*
> > +	 * Allocate a power of 2 size so alignment to that size is
> > +	 * guaranteed, since the hypercall input and output areas
> > +	 * must not cross a page boundary.
> > +	 */
> > +	input =3D kzalloc(roundup_pow_of_two(sizeof(input->header) +
> > +				sizeof(input->element[0])), GFP_ATOMIC);
> > +	output =3D kmalloc(roundup_pow_of_two(sizeof(*output)), GFP_ATOMIC);
> > +
> Check for null from these malloc routines? Here and in other places.

Between, is there a plan to setup a percpu input/output page for hypercall
input/output on ARM (like we do for x64)? I didn't check the specific size =
requirement
for this particular call, but, that generally will remove the need for thes=
e
allocations.