KVM: PPC: Book3S: Compile fix for ppc32 in HIOR access code
Alexander Graf [Tue, 13 Mar 2012 18:59:39 +0000 (19:59 +0100)]
We were failing to compile on book3s_32 with the following errors:

arch/powerpc/kvm/book3s_pr.c:883:45: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
arch/powerpc/kvm/book3s_pr.c:898:79: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]

Fix this by explicity casting the u64 to long before we use it as a pointer.

Also, on PPC32 we can not use get_user/put_user for 64bit wide variables,
as there is no single instruction that could load or store variables that big.

So instead, we have to use copy_from/to_user which works everywhere.

Reported-by: Jörg Sommer <joerg@alea.gnuu.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/kvm/book3s_pr.c

index 642d885..a657c44 100644 (file)
@@ -881,7 +881,8 @@ int kvm_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg)
 
        switch (reg->id) {
        case KVM_REG_PPC_HIOR:
-               r = put_user(to_book3s(vcpu)->hior, (u64 __user *)reg->addr);
+               r = copy_to_user((u64 __user *)(long)reg->addr,
+                               &to_book3s(vcpu)->hior, sizeof(u64));
                break;
        default:
                break;
@@ -896,7 +897,8 @@ int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg)
 
        switch (reg->id) {
        case KVM_REG_PPC_HIOR:
-               r = get_user(to_book3s(vcpu)->hior, (u64 __user *)reg->addr);
+               r = copy_from_user(&to_book3s(vcpu)->hior,
+                                  (u64 __user *)(long)reg->addr, sizeof(u64));
                if (!r)
                        to_book3s(vcpu)->hior_explicit = true;
                break;