diff options
author | Thomas Huth <thuth@redhat.com> | 2016-09-21 15:06:45 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-10-16 17:36:14 +0200 |
commit | 418fdccd410e34e358368b5439a20dd08d75c3c2 (patch) | |
tree | 4a197bbcd4009eda5179cfcc703f8d4971552b0e /arch/powerpc/kvm | |
parent | 5a4a45686a87f29aadf462c605df5f9361b56310 (diff) |
KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register
commit fa73c3b25bd8d0d393dc6109a1dba3c2aef0451e upstream.
The MMCR2 register is available twice, one time with number 785
(privileged access), and one time with number 769 (unprivileged,
but it can be disabled completely). In former times, the Linux
kernel was using the unprivileged register 769 only, but since
commit 8dd75ccb571f3c92c ("powerpc: Use privileged SPR number
for MMCR2"), it uses the privileged register 785 instead.
The KVM-PR code then of course also switched to use the SPR 785,
but this is causing older guest kernels to crash, since these
kernels still access 769 instead. So to support older kernels
with KVM-PR again, we have to support register 769 in KVM-PR, too.
Fixes: 8dd75ccb571f3c92c48014b3dabd3d51a115ab41
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/powerpc/kvm')
-rw-r--r-- | arch/powerpc/kvm/book3s_emulate.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c index 2afdb9c0937d..729f8faa95c5 100644 --- a/arch/powerpc/kvm/book3s_emulate.c +++ b/arch/powerpc/kvm/book3s_emulate.c @@ -498,6 +498,7 @@ int kvmppc_core_emulate_mtspr_pr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val) case SPRN_MMCR0: case SPRN_MMCR1: case SPRN_MMCR2: + case SPRN_UMMCR2: #endif break; unprivileged: @@ -640,6 +641,7 @@ int kvmppc_core_emulate_mfspr_pr(struct kvm_vcpu *vcpu, int sprn, ulong *spr_val case SPRN_MMCR0: case SPRN_MMCR1: case SPRN_MMCR2: + case SPRN_UMMCR2: case SPRN_TIR: #endif *spr_val = 0; |