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Date: Tue, 6 Jun 2023 10:04:13 -0700
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Subject: Re: [PATCH] KVM: arm64: Fix smp_processor_id() call in preemptible context
From: Sean Christopherson <seanjc@google.com>
To: Oliver Upton <oliver.upton@linux.dev>
Cc: Sebastian Ott <sebott@redhat.com>, kvmarm@lists.linux.dev, 
	linux-arm-kernel@lists.infradead.org, Marc Zyngier <maz@kernel.org>
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On Tue, Jun 06, 2023, Oliver Upton wrote:
> On Tue, Jun 06, 2023 at 03:46:09PM +0000, Sean Christopherson wrote:
> > I.e. can't you just do?
> 
> No, this would break the 'old' ABI, but if we decide to deliberately
> break it I prefer your suggestion over using CPU0.

Ah, if userspace pins the task when doing KVM_ARM_VCPU_PMU_V3_CTRL, then factoring
in the pCPU matters.