summaryrefslogtreecommitdiff
path: root/arch/arm64
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64')
-rw-r--r--arch/arm64/include/asm/kvm_host.h12
-rw-r--r--arch/arm64/kvm/reset.c43
2 files changed, 46 insertions, 9 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 5ecd457bce7d..f008f8866b2a 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -442,15 +442,7 @@ int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
-static inline void __cpu_init_stage2(void)
-{
- u32 ps;
-
- /* Sanity check for minimum IPA size support */
- ps = id_aa64mmfr0_parange_to_phys_shift(read_sysreg(id_aa64mmfr0_el1) & 0x7);
- WARN_ONCE(ps < 40,
- "PARange is %d bits, unsupported configuration!", ps);
-}
+static inline void __cpu_init_stage2(void) {}
/* Guest/host FPSIMD coordination helpers */
int kvm_arch_vcpu_run_map_fp(struct kvm_vcpu *vcpu);
@@ -513,6 +505,8 @@ static inline int kvm_arm_have_ssbd(void)
void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu);
void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu);
+void kvm_set_ipa_limit(void);
+
#define __KVM_HAVE_ARCH_VM_ALLOC
struct kvm *kvm_arch_alloc_vm(void);
void kvm_arch_free_vm(struct kvm *kvm);
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 2bf41e007390..96b3f50101bc 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -34,6 +34,9 @@
#include <asm/kvm_coproc.h>
#include <asm/kvm_mmu.h>
+/* Maximum phys_shift supported for any VM on this host */
+static u32 kvm_ipa_limit;
+
/*
* ARMv8 Reset Values
*/
@@ -135,6 +138,46 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
return kvm_timer_vcpu_reset(vcpu);
}
+void kvm_set_ipa_limit(void)
+{
+ unsigned int ipa_max, pa_max, va_max, parange;
+
+ parange = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1) & 0x7;
+ pa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
+
+ /* Clamp the IPA limit to the PA size supported by the kernel */
+ ipa_max = (pa_max > PHYS_MASK_SHIFT) ? PHYS_MASK_SHIFT : pa_max;
+ /*
+ * Since our stage2 table is dependent on the stage1 page table code,
+ * we must always honor the following condition:
+ *
+ * Number of levels in Stage1 >= Number of levels in Stage2.
+ *
+ * So clamp the ipa limit further down to limit the number of levels.
+ * Since we can concatenate upto 16 tables at entry level, we could
+ * go upto 4bits above the maximum VA addressible with the current
+ * number of levels.
+ */
+ va_max = PGDIR_SHIFT + PAGE_SHIFT - 3;
+ va_max += 4;
+
+ if (va_max < ipa_max)
+ ipa_max = va_max;
+
+ /*
+ * If the final limit is lower than the real physical address
+ * limit of the CPUs, report the reason.
+ */
+ if (ipa_max < pa_max)
+ pr_info("kvm: Limiting the IPA size due to kernel %s Address limit\n",
+ (va_max < pa_max) ? "Virtual" : "Physical");
+
+ WARN(ipa_max < KVM_PHYS_SHIFT,
+ "KVM IPA limit (%d bit) is smaller than default size\n", ipa_max);
+ kvm_ipa_limit = ipa_max;
+ kvm_info("IPA Size Limit: %dbits\n", kvm_ipa_limit);
+}
+
/*
* Configure the VTCR_EL2 for this VM. The VTCR value is common
* across all the physical CPUs on the system. We use system wide