[patch 3/3] kvm: allow qemu to set EPT identity mapping address

Marcelo Tosatti
2010-03-09T01:58:20Z

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From: Sheng Yang <sheng@linux.intel.com>

If we use larger BIOS image than current 256KB, we would need move reserved
TSS and EPT identity mapping pages. Currently TSS support this, but not
EPT.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: qemu-kvm/target-i386/kvm.c
===================================================================
--- qemu-kvm.orig/target-i386/kvm.c
+++ qemu-kvm/target-i386/kvm.c
@@ -341,6 +341,24 @@ static int kvm_has_msr_star(CPUState *en
return 0;
}

+static int kvm_init_identity_map_page(KVMState *s)
+{
+#ifdef KVM_CAP_SET_IDENTITY_MAP_ADDR
+ int ret;
+ uint64_t addr = 0xfffbc000;
+
+ if (!kvm_check_extension(s, KVM_CAP_SET_IDENTITY_MAP_ADDR))
+ return 0;
+
+ ret = kvm_vm_ioctl(s, KVM_SET_IDENTITY_MAP_ADDR, &addr);
+ if (ret < 0) {
+ fprintf(stderr, "kvm_set_identity_map_addr: %s\n", strerror(ret));
+ return ret;
+ }
+#endif
+ return 0;
+}
+
int kvm_arch_init(KVMState *s, int smp_cpus)
{
int ret;
@@ -368,7 +386,11 @@ int kvm_arch_init(KVMState *s, int smp_c
perror("e820_add_entry() table is full");
exit(1);
}
- return kvm_vm_ioctl(s, KVM_SET_TSS_ADDR, 0xfffbd000);
+ ret = kvm_vm_ioctl(s, KVM_SET_TSS_ADDR, 0xfffbd000);
+ if (ret < 0)
+ return ret;
+
+ return kvm_init_identity_map_page(s);
}

static void set_v8086_seg(struct kvm_segment *lhs, const SegmentCache *rhs)