On Thu, 31 May 2012 10:04:14 +0100, Marc Zyngier <marc.zyngier at arm.com> wrote:
> +static bool write_dcsw(struct kvm_vcpu *vcpu,
> + const struct coproc_params *p,
> + unsigned long cp15_reg)
> +{
> + u32 val;
> +
> + val = *vcpu_reg(vcpu, p->Rt1);
> +
> + switch(p->CRm) {
> + case 6: /* Upgrade DCISW to DCCISW, as per HCR.SWIO */
> + case 14: /* DCCISW */
> + asm volatile("mcr p15, 0, %0, c7, c14, 2" : : "r" (val));
> + break;
> +
> + case 10: /* DCCSW */
> + asm volatile("mcr p15, 0, %0, c7, c10, 2" : : "r" (val));
> + break;
> + }
> +
> + cpumask_setall(&vcpu->arch.require_dcache_flush);
> + cpumask_clear_cpu(vcpu->cpu, &vcpu->arch.require_dcache_flush);
Hmm, but vcpu->cpu is not necessarily smp_processor_id() here.
I think you do need get_cpu() and put_cpu() around this:
kvm_arch_vcpu_load() will do a full flush if vcpu->cpu !=
smp_processor_id().
Cheers,
Rusty.
