[RFC PATCH 2/3] kvm: arm/arm64: vgic-vits: free its resource when vm reboot/reset

wanghaibin
2017-09-06T13:04:24Z

This patch fix the migrate save tables failure.

When the virtual machine is in booting and the devices haven't initialized,
the all virtual dte/ite may be invalid. If migrate at this moment, the save
tables interface traversal device list, and check the dte is valid or not.
if not, it will return the -EINVAL.

This patch try to free the its list resource when vm reboot or reset to avoid this.

Signed-off-by: wanghaibin <wanghaibin.wang@huawei.com>
---
virt/kvm/arm/arm.c | 5 ++++-
virt/kvm/arm/vgic/vgic-its.c | 10 ++++++++++
virt/kvm/arm/vgic/vgic.h | 1 +
3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index a39a1e1..db7632d 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -46,6 +46,7 @@
#include <asm/kvm_coproc.h>
#include <asm/kvm_psci.h>
#include <asm/sections.h>
+#include "vgic.h"

#ifdef REQUIRES_VIRT
__asm__(".arch_extension virt");
@@ -901,8 +902,10 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
* Ensure a rebooted VM will fault in RAM pages and detect if the
* guest MMU is turned off and flush the caches as needed.
*/
- if (vcpu->arch.has_run_once)
+ if (vcpu->arch.has_run_once) {
stage2_unmap_vm(vcpu->kvm);
+ vgic_its_free_resource(vcpu->kvm);
+ }

vcpu_reset_hcr(vcpu);

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 25d614f..5c20352 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -2467,6 +2467,16 @@ static int vgic_its_get_attr(struct kvm_device *dev,
.has_attr = vgic_its_has_attr,
};

+void vgic_its_free_resource(struct kvm *kvm)
+{
+ struct kvm_device *dev, *tmp;
+
+ list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
+ if(dev->ops == &kvm_arm_vgic_its_ops)
+ vgic_its_free_list(kvm, dev->private);
+ }
+}
+
int kvm_vgic_register_its_device(void)
{
return kvm_register_device_ops(&kvm_arm_vgic_its_ops,
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index c2be5b7..fbcbdfd 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -222,5 +222,6 @@ int vgic_v3_line_level_info_uaccess(struct kvm_vcpu *vcpu, bool is_write,

bool lock_all_vcpus(struct kvm *kvm);
void unlock_all_vcpus(struct kvm *kvm);
+void vgic_its_free_resource(struct kvm *kvm);

#endif
--
1.8.3.1