[for,3.14.y,stable,39/47] arm/arm64: KVM: Correct KVM_ARM_VCPU_INIT power off option

Message ID 1430704362-6292-40-git-send-email-shannon.zhao@linaro.org
State New
Headers show

Commit Message

Shannon Zhao May 4, 2015, 1:52 a.m.
From: Christoffer Dall <christoffer.dall@linaro.org>

commit 3ad8b3de526a76fbe9466b366059e4958957b88f upstream.

The implementation of KVM_ARM_VCPU_INIT is currently not doing what
userspace expects, namely making sure that a vcpu which may have been
turned off using PSCI is returned to its initial state, which would be
powered on if userspace does not set the KVM_ARM_VCPU_POWER_OFF flag.

Implement the expected functionality and clarify the ABI.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
 Documentation/virtual/kvm/api.txt | 3 ++-
 arch/arm/kvm/arm.c                | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)


diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 6cd63a9..bc6d617 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2344,7 +2344,8 @@  should be created before this ioctl is invoked.
 Possible features:
 	- KVM_ARM_VCPU_POWER_OFF: Starts the CPU in a power-off state.
-	  Depends on KVM_CAP_ARM_PSCI.
+	  Depends on KVM_CAP_ARM_PSCI.  If not set, the CPU will be powered on
+	  and execute guest code when KVM_RUN is called.
 	- KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode.
 	  Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only).
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 4a7f538..9c58125 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -680,6 +680,8 @@  static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
 	if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
 		vcpu->arch.pause = true;
+	else
+		vcpu->arch.pause = false;
 	return 0;