The VTTBR initialization code was buggy and hard to read. This code
cleans it up slightly.
Signed-off-by: Christoffer Dall <c.dall@xxxxxxxxxxxxxxxxxxxxxx>
---
arch/arm/include/asm/kvm_arm.h | 4 ++++
arch/arm/kvm/arm.c | 7 ++++---
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index e1e39d6..8f5dd22 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -144,6 +144,10 @@
#else
#define VTTBR_X (5 - VTCR_GUEST_T0SZ)
#endif
+#define VTTBR_BADDR_SHIFT (VTTBR_X - 1)
+#define VTTBR_BADDR_MASK (((1LLU << (40 - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT)
+#define VTTBR_VMID_SHIFT (48LLU)
+#define VTTBR_VMID_MASK (0xffLLU << VTTBR_VMID_SHIFT)
/* Hyp Syndrome Register (HSR) bits */
#define HSR_EC_SHIFT (26)
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 69bec17..e62ba49 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -427,6 +427,7 @@ static bool need_new_vmid_gen(struct kvm *kvm)
static void update_vttbr(struct kvm *kvm)
{
phys_addr_t pgd_phys;
+ u64 vmid;
if (!need_new_vmid_gen(kvm))
return;
@@ -452,9 +453,9 @@ static void update_vttbr(struct kvm *kvm)
/* update vttbr to be used with the new vmid */
pgd_phys = virt_to_phys(kvm->arch.pgd);
- kvm->arch.vttbr = pgd_phys & ((1LLU << 40) - 1)
- & ~((2 << VTTBR_X) - 1);
- kvm->arch.vttbr |= (u64)(kvm->arch.vmid) << 48;
+ vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK;
+ kvm->arch.vttbr = pgd_phys & VTTBR_BADDR_MASK;
+ kvm->arch.vttbr |= vmid;
spin_unlock(&kvm_vmid_lock);
}
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