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From: Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
Subject: Re: Reason for extra struct kvm_run parameter in MMIO handling?
Date: Mon, 9 Feb 2015 17:21:54 +0100
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To: Andre Przywara <andre.przywara@arm.com>
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2015-02-06 17:30+0000, Andre Przywara:
> As kvm_run is a member of kvm_vcpu, the vcpu alone should be sufficient,
> right?

Yes.

> Also I see the very top of the call chain is effectively:
> kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);

:(

> So is that just legacy code still lingering around from the dawn of time
> and nobody dared to rework this or is there a particular reason for
> doing so?

Probably laziness in 9a2bb7f486dc639a1cf2ad803bf2227f0dc0809d.

> I am asking because I lack the kvm_run pointer in the MMIO handler, so I
> just use vcpu->run and I wonder if there are potential issues in doing so.

We do it at few places already, so there, hopefully, is no problem.