| Message ID | 1457482784-82531-1-git-send-email-dmatlack@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 09/03/2016 01:19, David Matlack wrote: > When growing halt-polling, there is no check that the poll time exceeds > the limit. It's possible for vcpu->halt_poll_ns grow once past > halt_poll_ns, and stay there until a halt which takes longer than > vcpu->halt_poll_ns. For example, booting a Linux guest with > halt_poll_ns=11000: > > ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 0 (shrink 10000) > ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 10000 (grow 0) > ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (grow 10000) > > Signed-off-by: David Matlack <dmatlack@google.com> > --- > virt/kvm/kvm_main.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index a11cfd2..9102ae1 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -1952,6 +1952,9 @@ static void grow_halt_poll_ns(struct kvm_vcpu *vcpu) > else > val *= halt_poll_ns_grow; > > + if (val > halt_poll_ns) > + val = halt_poll_ns; > + > vcpu->halt_poll_ns = val; > trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old); > } > Applied to kvm/master, thanks. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a11cfd2..9102ae1 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1952,6 +1952,9 @@ static void grow_halt_poll_ns(struct kvm_vcpu *vcpu) else val *= halt_poll_ns_grow; + if (val > halt_poll_ns) + val = halt_poll_ns; + vcpu->halt_poll_ns = val; trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old); }
When growing halt-polling, there is no check that the poll time exceeds the limit. It's possible for vcpu->halt_poll_ns grow once past halt_poll_ns, and stay there until a halt which takes longer than vcpu->halt_poll_ns. For example, booting a Linux guest with halt_poll_ns=11000: ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 0 (shrink 10000) ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 10000 (grow 0) ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (grow 10000) Signed-off-by: David Matlack <dmatlack@google.com> --- virt/kvm/kvm_main.c | 3 +++ 1 file changed, 3 insertions(+)