On Fri, Dec 21, 2018 at 02:28:39PM +1100, Suraj Jitindar Singh wrote:
> We already hold the kvm->mmu_lock spin lock across updating the rc bits
> in the pte for the L1 guest. Continue to hold the lock across updating
> the rc bits in the pte for the nested guest as well to prevent
> invalidations from occurring.
>
> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@xxxxxxxxx>
Reviewed-by: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
> ---
> arch/powerpc/kvm/book3s_hv_nested.c | 18 ++++++++++++------
> 1 file changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c
> index 401d2ecbebc5..0dfbf093bde5 100644
> --- a/arch/powerpc/kvm/book3s_hv_nested.c
> +++ b/arch/powerpc/kvm/book3s_hv_nested.c
> @@ -1049,7 +1049,7 @@ static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
> struct kvm *kvm = vcpu->kvm;
> bool writing = !!(dsisr & DSISR_ISSTORE);
> u64 pgflags;
> - bool ret;
> + long ret;
>
> /* Are the rc bits set in the L1 partition scoped pte? */
> pgflags = _PAGE_ACCESSED;
> @@ -1062,16 +1062,22 @@ static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
> /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */
> ret = kvmppc_hv_handle_set_rc(kvm, kvm->arch.pgtable, writing,
> gpte.raddr, kvm->arch.lpid);
> - spin_unlock(&kvm->mmu_lock);
> - if (!ret)
> - return -EINVAL;
> + if (!ret) {
> + ret = -EINVAL;
> + goto out_unlock;
> + }
>
> /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */
> ret = kvmppc_hv_handle_set_rc(kvm, gp->shadow_pgtable, writing, n_gpa,
> gp->shadow_lpid);
> if (!ret)
> - return -EINVAL;
> - return 0;
> + ret = -EINVAL;
> + else
> + ret = 0;
> +
> +out_unlock:
> + spin_unlock(&kvm->mmu_lock);
> + return ret;
> }
>
> static inline int kvmppc_radix_level_to_shift(int level)
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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