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[RFC,15/32] KVM: PPC: Book3S HV: Clear partition table entry on vm teardown

Message ID 1537524123-9578-16-git-send-email-paulus@ozlabs.org
State Superseded
Headers show
Series KVM: PPC: Book3S HV: Nested HV virtualization | expand

Commit Message

Paul Mackerras Sept. 21, 2018, 10:01 a.m. UTC 
From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

When destroying a VM we return the LPID to the pool, however we never
zero the partition table entry. This is instead done when we reallocate
the LPID.

Zero the partition table entry on VM teardown before returning the LPID
to the pool. This means if we were running as a nested hypervisor the
real hypervisor could use this to determine when it can free resources.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/kvm/book3s_hv.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

David Gibson Sept. 26, 2018, 3:36 a.m. UTC | #1 
On Fri, Sep 21, 2018 at 08:01:46PM +1000, Paul Mackerras wrote:
> From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
> 
> When destroying a VM we return the LPID to the pool, however we never
> zero the partition table entry. This is instead done when we reallocate
> the LPID.
> 
> Zero the partition table entry on VM teardown before returning the LPID
> to the pool. This means if we were running as a nested hypervisor the
> real hypervisor could use this to determine when it can free resources.
> 
> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  arch/powerpc/kvm/book3s_hv.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index be8c863..82d6668 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -4499,13 +4499,19 @@ static void kvmppc_core_destroy_vm_hv(struct kvm *kvm)
>  
>  	kvmppc_free_vcores(kvm);
>  
> -	kvmppc_free_lpid(kvm->arch.lpid);
>  
>  	if (kvm_is_radix(kvm))
>  		kvmppc_free_radix(kvm);
>  	else
>  		kvmppc_free_hpt(&kvm->arch.hpt);
>  
> +	/* Perform global invalidation and return lpid to the pool */
> +	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
> +		kvm->arch.process_table = 0;
> +		kvmppc_setup_partition_table(kvm);
> +	}
> +	kvmppc_free_lpid(kvm->arch.lpid);
> +
>  	kvmppc_free_pimap(kvm);
>  }
>
diff mbox series

Patch

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index be8c863..82d6668 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4499,13 +4499,19 @@  static void kvmppc_core_destroy_vm_hv(struct kvm *kvm)
 
 	kvmppc_free_vcores(kvm);
 
-	kvmppc_free_lpid(kvm->arch.lpid);
 
 	if (kvm_is_radix(kvm))
 		kvmppc_free_radix(kvm);
 	else
 		kvmppc_free_hpt(&kvm->arch.hpt);
 
+	/* Perform global invalidation and return lpid to the pool */
+	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
+		kvm->arch.process_table = 0;
+		kvmppc_setup_partition_table(kvm);
+	}
+	kvmppc_free_lpid(kvm->arch.lpid);
+
 	kvmppc_free_pimap(kvm);
 }