[PATCH v2 20/28] ARM: KVM: Change kvm_call_hyp return type to unsigned long

Marc Zyngier marc.zyngier at arm.com
Wed Feb 10 08:07:07 PST 2016


On 09/02/16 18:28, Christoffer Dall wrote:
> On Thu, Feb 04, 2016 at 11:00:37AM +0000, Marc Zyngier wrote:
>> Having u64 as the kvm_call_hyp return type is problematic, as
>> it forces all kind of tricks for the return values from HYP
>> to be promoted to 64bit (LE has the LSB in r0, and BE has them
>> in r1).
>>
>> Since the only user of the return value is perfectly happy with
>> a 32bit value, let's make kvm_call_hyp return an unsigned long,
>> which is 32bit on ARM.
> 
> I wonder why I ever did this as a u64...

Probably to cater for the largest possible return value, before we
started looking at BE... ;-)

> should the arm64 counterpart be modified to an unsigned long as well?

That'd be a sensible change.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...



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