KVM: PPC: Book3S: Fix compile error that occurs with some gcc versions
authorPaul Mackerras <paulus@ozlabs.org>
Tue, 13 Feb 2018 04:45:21 +0000 (15:45 +1100)
committerPaul Mackerras <paulus@ozlabs.org>
Tue, 13 Feb 2018 04:45:21 +0000 (15:45 +1100)
Some versions of gcc generate a warning that the variable "emulated"
may be used uninitialized in function kvmppc_handle_load128_by2x64().
It would be used uninitialized if kvmppc_handle_load128_by2x64 was
ever called with vcpu->arch.mmio_vmx_copy_nums == 0, but neither of
the callers ever do that, so there is no actual bug.  When gcc
generates a warning, it causes the build to fail because arch/powerpc
is compiled with -Werror.

This silences the warning by initializing "emulated" to EMULATE_DONE.

Fixes: 09f984961c13 ("KVM: PPC: Book3S: Add MMIO emulation for VMX instructions")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
arch/powerpc/kvm/powerpc.c

index 0083142..52c2053 100644 (file)
@@ -1345,7 +1345,7 @@ static int kvmppc_emulate_mmio_vsx_loadstore(struct kvm_vcpu *vcpu,
 int kvmppc_handle_load128_by2x64(struct kvm_run *run, struct kvm_vcpu *vcpu,
                unsigned int rt, int is_default_endian)
 {
-       enum emulation_result emulated;
+       enum emulation_result emulated = EMULATE_DONE;
 
        while (vcpu->arch.mmio_vmx_copy_nums) {
                emulated = __kvmppc_handle_load(run, vcpu, rt, 8,