[3.16.y-ckt stable] Patch "KVM: s390: flush CPU on load control" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    KVM: s390: flush CPU on load control

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt4.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From fca4638cf8bb1d7fe976e05f05976f111c393d99 Mon Sep 17 00:00:00 2001
From: Christian Borntraeger <borntraeger at de.ibm.com>
Date: Fri, 31 Oct 2014 09:24:20 +0100
Subject: KVM: s390: flush CPU on load control

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 at de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck at de.ibm.com>
Reviewed-by: David Hildenbrand <dahi at linux.vnet.ibm.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 arch/s390/kvm/priv.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index f89c1cd67751..9f41229df1aa 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -800,7 +800,7 @@ int kvm_s390_handle_lctl(struct kvm_vcpu *vcpu)
 			break;
 		reg = (reg + 1) % 16;
 	} while (1);
-
+	kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
 	return 0;
 }

@@ -872,7 +872,7 @@ static int handle_lctlg(struct kvm_vcpu *vcpu)
 			break;
 		reg = (reg + 1) % 16;
 	} while (1);
-
+	kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
 	return 0;
 }

--
2.1.4