mips/kvm: Fix Big endian 32-bit register access

Fix access to 32-bit registers on big endian targets. The pointer passed
to the kernel must be for the actual 32-bit value, not a temporary
64-bit value, otherwise on big endian systems the kernel will only
interpret the upper half.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Leon Alrae <leon.alrae@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: kvm@vger.kernel.org
Cc: qemu-stable@nongnu.org
Message-Id: <1429871214-23514-2-git-send-email-james.hogan@imgtec.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit f8b3e48b2d269551cd40f94770dc20da2f402325)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

diff --git a/target-mips/kvm.c b/target-mips/kvm.c
index 4d1f7ead8142edc22f3c33fa706f9880f2df0a26..1597bbeac17a15fd4c94deffa2ee1081c01b308f 100644 (file)
--- a/target-mips/kvm.c
+++ b/target-mips/kvm.c
@@ -240,10 +240,9 @@ int kvm_mips_set_ipi_interrupt(MIPSCPU *cpu, int irq, int level)
 static inline int kvm_mips_put_one_reg(CPUState *cs, uint64_t reg_id,
                                        int32_t *addr)
 {
-    uint64_t val64 = *addr;
     struct kvm_one_reg cp0reg = {
         .id = reg_id,
-        .addr = (uintptr_t)&val64
+        .addr = (uintptr_t)addr
     };
 
     return kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &cp0reg);
@@ -275,18 +274,12 @@ static inline int kvm_mips_put_one_reg64(CPUState *cs, uint64_t reg_id,
 static inline int kvm_mips_get_one_reg(CPUState *cs, uint64_t reg_id,
                                        int32_t *addr)
 {
-    int ret;
-    uint64_t val64 = 0;
     struct kvm_one_reg cp0reg = {
         .id = reg_id,
-        .addr = (uintptr_t)&val64
+        .addr = (uintptr_t)addr
     };
 
-    ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &cp0reg);
-    if (ret >= 0) {
-        *addr = val64;
-    }
-    return ret;
+    return kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &cp0reg);
 }
 
 static inline int kvm_mips_get_one_ulreg(CPUState *cs, uint64 reg_id,