diff mbox series

[5.10,010/289] kvm: Cap halt polling at kvm->max_halt_poll_ns

Message ID 20210517140305.525322001@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH May 17, 2021, 1:58 p.m. UTC 
From: David Matlack <dmatlack@google.com>

commit 258785ef08b323bddd844b4926a32c2b2045a1b0 upstream.

When growing halt-polling, there is no check that the poll time exceeds
the per-VM limit. It's possible for vcpu->halt_poll_ns to grow past
kvm->max_halt_poll_ns and stay there until a halt which takes longer
than kvm->halt_poll_ns.

Signed-off-by: David Matlack <dmatlack@google.com>
Signed-off-by: Venkatesh Srinivas <venkateshs@chromium.org>
Message-Id: <20210506152442.4010298-1-venkateshs@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 virt/kvm/kvm_main.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2717,8 +2717,8 @@  static void grow_halt_poll_ns(struct kvm
 	if (val < grow_start)
 		val = grow_start;
 
-	if (val > halt_poll_ns)
-		val = halt_poll_ns;
+	if (val > vcpu->kvm->max_halt_poll_ns)
+		val = vcpu->kvm->max_halt_poll_ns;
 
 	vcpu->halt_poll_ns = val;
 out: