diff options
author | Paul Mackerras <paulus@ozlabs.org> | 2016-05-05 16:17:10 +1000 |
---|---|---|
committer | Paul Mackerras <paulus@samba.org> | 2016-05-11 21:19:10 +1000 |
commit | eb8b0560160d8363bc40ca05a75ef144cebaae72 (patch) | |
tree | 6f550cfc3b32b335984bbd7f8ed6760ff799364b /arch/powerpc/kvm/powerpc.c | |
parent | ade3ac660a1813344bcf4fe58b9ac5fbe7c0ed4b (diff) |
KVM: PPC: Fix emulated MMIO sign-extension
When the guest does a sign-extending load instruction (such as lha
or lwa) to an emulated MMIO location, it results in a call to
kvmppc_handle_loads() in the host. That function sets the
vcpu->arch.mmio_sign_extend flag and calls kvmppc_handle_load()
to do the rest of the work. However, kvmppc_handle_load() sets
the mmio_sign_extend flag to 0 unconditionally, so the sign
extension never gets done.
To fix this, we rename kvmppc_handle_load to __kvmppc_handle_load
and add an explicit parameter to indicate whether sign extension
is required. kvmppc_handle_load() and kvmppc_handle_loads() then
become 1-line functions that just call __kvmppc_handle_load()
with the extra parameter.
Reported-by: Bin Lu <lblulb@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/kvm/powerpc.c')
-rw-r--r-- | arch/powerpc/kvm/powerpc.c | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 6a68730774ee..02416fea7653 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -800,9 +800,9 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, } } -int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, - unsigned int rt, unsigned int bytes, - int is_default_endian) +static int __kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, + unsigned int rt, unsigned int bytes, + int is_default_endian, int sign_extend) { int idx, ret; bool host_swabbed; @@ -827,7 +827,7 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, vcpu->arch.mmio_host_swabbed = host_swabbed; vcpu->mmio_needed = 1; vcpu->mmio_is_write = 0; - vcpu->arch.mmio_sign_extend = 0; + vcpu->arch.mmio_sign_extend = sign_extend; idx = srcu_read_lock(&vcpu->kvm->srcu); @@ -844,6 +844,13 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, return EMULATE_DO_MMIO; } + +int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, + unsigned int rt, unsigned int bytes, + int is_default_endian) +{ + return __kvmppc_handle_load(run, vcpu, rt, bytes, is_default_endian, 0); +} EXPORT_SYMBOL_GPL(kvmppc_handle_load); /* Same as above, but sign extends */ @@ -851,12 +858,7 @@ int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned int rt, unsigned int bytes, int is_default_endian) { - int r; - - vcpu->arch.mmio_sign_extend = 1; - r = kvmppc_handle_load(run, vcpu, rt, bytes, is_default_endian); - - return r; + return __kvmppc_handle_load(run, vcpu, rt, bytes, is_default_endian, 1); } int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu, |