[PATCH v4 06/11] KVM: arm/arm64: vgic-its: Check GITS_CBASER validity before processing commands

From: Eric Auger
Date: Tue Oct 17 2017 - 03:10:59 EST


At the moment vgic_its_process_commands() does not
check the CBASER is valid before processing any command.
Let's fix that.

Also rename cbaser local variable into cbaser_pa to avoid
any confusion with the full register.

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
virt/kvm/arm/vgic/vgic-its.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 3b539d4..e18f1e4 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1301,17 +1301,20 @@ static void vgic_mmio_write_its_cbaser(struct kvm *kvm, struct vgic_its *its,
/* Must be called with the cmd_lock held. */
static void vgic_its_process_commands(struct kvm *kvm, struct vgic_its *its)
{
- gpa_t cbaser;
+ gpa_t cbaser_pa;
u64 cmd_buf[4];

- /* Commands are only processed when the ITS is enabled. */
- if (!its->enabled)
+ /*
+ * Commands are only processed when the ITS is enabled and
+ * CBASER is valid
+ */
+ if (!its->enabled || (!(its->cbaser & GITS_CBASER_VALID)))
return;

- cbaser = CBASER_ADDRESS(its->cbaser);
+ cbaser_pa = CBASER_ADDRESS(its->cbaser);

while (its->cwriter != its->creadr) {
- int ret = kvm_read_guest(kvm, cbaser + its->creadr,
+ int ret = kvm_read_guest(kvm, cbaser_pa + its->creadr,
cmd_buf, ITS_CMD_SIZE);
/*
* If kvm_read_guest() fails, this could be due to the guest
--
2.5.5