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ARM: KVM: fix unbalanced get_cpu() in access_dcsw

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In the very unlikely event where a guest would be foolish enough to
*read* from a write-only cache maintainance register, we end up
with preemption disabled, due to a misplaced get_cpu().

Just move the "is_write" test outside of the critical section.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Marc Zyngier 2013-04-17 12:09:09 -07:00 committed by Linus Torvalds
parent fca83168aa
commit 15bbc1b28f
1 changed files with 2 additions and 2 deletions
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4
arch/arm/kvm/coproc.c
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@ -79,11 +79,11 @@ static bool access_dcsw(struct kvm_vcpu *vcpu,
u32 val;
int cpu;
cpu = get_cpu();
if (!p->is_write)
return read_from_write_only(vcpu, p);
cpu = get_cpu();
cpumask_setall(&vcpu->arch.require_dcache_flush);
cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush);