[PATCH 3.18 065/150] KVM: s390: flush CPU on load control

Greg Kroah-Hartman
2015-01-14T07:27:19Z

From: Christian Borntraeger <borntraeger@de.ibm.com>

commit 2dca485f8740208604543c3960be31a5dd3ea603 upstream.

some control register changes will flush some aspects of the CPU, e.g.
POP explicitely mentions that for CR9-CR11 "TLBs may be cleared".
Instead of trying to be clever and only flush on specific CRs, let
play safe and flush on all lctl(g) as future machines might define
new bits in CRs. Load control intercept should not happen that often.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/s390/kvm/priv.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -791,7 +791,7 @@ int kvm_s390_handle_lctl(struct kvm_vcpu
break;
reg = (reg + 1) % 16;
} while (1);
-
+ kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
return 0;
}

@@ -863,7 +863,7 @@ static int handle_lctlg(struct kvm_vcpu
break;
reg = (reg + 1) % 16;
} while (1);
-
+ kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
return 0;
}