Re: [kvmtool PATCH v6 22/18] kvmtool: arm: Add support for creating VM with PA size

From: Marc Zyngier
Date: Mon Oct 01 2018 - 10:13:22 EST


On 26/09/18 17:32, Suzuki K Poulose wrote:
Specify the physical size for the VM encoded in the vm type.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
arm/include/arm-common/kvm-arch.h | 6 +++++-
arm/kvm.c | 32 +++++++++++++++++++++++++++++++
2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/arm/include/arm-common/kvm-arch.h b/arm/include/arm-common/kvm-arch.h
index b29b4b1..d77f3ac 100644
--- a/arm/include/arm-common/kvm-arch.h
+++ b/arm/include/arm-common/kvm-arch.h
@@ -44,7 +44,11 @@
#define KVM_IRQ_OFFSET GIC_SPI_IRQ_BASE
-#define KVM_VM_TYPE 0
+extern unsigned long kvm_arm_type;
+extern void kvm__arch_init_hyp(struct kvm *kvm);
+
+#define KVM_VM_TYPE kvm_arm_type
+#define kvm__arch_init_hyp kvm__arch_init_hyp
#define VIRTIO_DEFAULT_TRANS(kvm) \
((kvm)->cfg.arch.virtio_trans_pci ? VIRTIO_PCI : VIRTIO_MMIO)
diff --git a/arm/kvm.c b/arm/kvm.c
index eac2ad2..c8db6b3 100644
--- a/arm/kvm.c
+++ b/arm/kvm.c
@@ -11,6 +11,8 @@
#include <linux/kvm.h>
#include <linux/sizes.h>
+unsigned long kvm_arm_type;
+
struct kvm_ext kvm_req_ext[] = {
{ DEFINE_KVM_EXT(KVM_CAP_IRQCHIP) },
{ DEFINE_KVM_EXT(KVM_CAP_ONE_REG) },
@@ -18,6 +20,36 @@ struct kvm_ext kvm_req_ext[] = {
{ 0, 0 },
};
+#ifndef KVM_CAP_ARM_VM_IPA_SIZE
+#define KVM_CAP_ARM_VM_IPA_SIZE 159
+#endif

Note that when merged on top of 4.19-rc5, this is already 160. I assume this will be even different once this lands in mainline.

Thanks,

M.

+
+#ifndef KVM_VM_TYPE_ARM_IPA_SIZE
+#define KVM_VM_TYPE_ARM_IPA_SIZE_MASK 0xffULL
+#define KVM_VM_TYPE_ARM_IPA_SIZE(x) \
+ ((x) & KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
+#endif
+
+void kvm__arch_init_hyp(struct kvm *kvm)
+{
+ int max_ipa;
+
+ if (!kvm->cfg.arch.phys_shift)
+ kvm->cfg.arch.phys_shift = 40;
+ if (kvm->cfg.arch.phys_shift == 40)
+ return;
+ max_ipa = ioctl(kvm->sys_fd,
+ KVM_CHECK_EXTENSION, KVM_CAP_ARM_VM_IPA_SIZE);
+ if (!max_ipa)
+ die("Kernel doesn't support IPA size configuration\n");
+ if ((kvm->cfg.arch.phys_shift > max_ipa) ||
+ (kvm->cfg.arch.phys_shift < 32))
+ die("Requested PA size (%u) is not supported by the host"
+ " [32 - %u]bit\n",
+ kvm->cfg.arch.phys_shift, max_ipa);
+ kvm_arm_type = KVM_VM_TYPE_ARM_IPA_SIZE(kvm->cfg.arch.phys_shift);
+}
+
bool kvm__arch_cpu_supports_vm(void)
{
/* The KVM capability check is enough. */



--
Jazz is not dead. It just smells funny...