[PATCH 3.4 033/176] KVM: s390: flush CPU on load control

From: lizf
Date: Thu Apr 09 2015 - 06:03:17 EST


From: Christian Borntraeger <borntraeger@xxxxxxxxxx>

3.4.107-rc1 review patch. If anyone has any objections, please let me know.

------------------


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@xxxxxxxxxx>
Acked-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
Reviewed-by: David Hildenbrand <dahi@xxxxxxxxxxxxxxxxxx>
[lizf: Backported to 3.4:
- adjust filename
- adjust context]
Signed-off-by: Zefan Li <lizefan@xxxxxxxxxx>
---
arch/s390/kvm/intercept.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 3614565..f10fef6 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -58,6 +58,7 @@ 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;
}

@@ -97,6 +98,7 @@ static int handle_lctl(struct kvm_vcpu *vcpu)
break;
reg = (reg + 1) % 16;
} while (1);
+ kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
return 0;
}

--
1.9.1

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