diff options
| author | Thomas Huth <thuth@redhat.com> | 2016-05-18 22:01:20 +0300 |
|---|---|---|
| committer | Paul Mackerras <paulus@ozlabs.org> | 2016-06-20 07:11:25 +0300 |
| commit | 708e75a3ee750dce1072134e630d66c4e6eaf63c (patch) | |
| tree | 7827ed2ebc0d34d0421fb3e822fb82c080b920be /arch/powerpc/kvm/emulate.c | |
| parent | 64672c95ea4c2f7096e519e826076867e8ef0938 (diff) | |
| download | linux-708e75a3ee750dce1072134e630d66c4e6eaf63c.tar.xz | |
KVM: PPC: Book3S PR: Fix illegal opcode emulation
If kvmppc_handle_exit_pr() calls kvmppc_emulate_instruction() to emulate
one instruction (in the BOOK3S_INTERRUPT_H_EMUL_ASSIST case), it calls
kvmppc_core_queue_program() afterwards if kvmppc_emulate_instruction()
returned EMULATE_FAIL, so the guest gets an program interrupt for the
illegal opcode.
However, the kvmppc_emulate_instruction() also tried to inject a
program exception for this already, so the program interrupt gets
injected twice and the return address in srr0 gets destroyed.
All other callers of kvmppc_emulate_instruction() are also injecting
a program interrupt, and since the callers have the right knowledge
about the srr1 flags that should be used, it is the function
kvmppc_emulate_instruction() that should _not_ inject program
interrupts, so remove the kvmppc_core_queue_program() here.
This fixes the issue discovered by Laurent Vivier with kvm-unit-tests
where the logs are filled with these messages when the test tries
to execute an illegal instruction:
Couldn't emulate instruction 0x00000000 (op 0 xop 0)
kvmppc_handle_exit_pr: emulation at 700 failed (00000000)
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'arch/powerpc/kvm/emulate.c')
| -rw-r--r-- | arch/powerpc/kvm/emulate.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index 5cc2e7af3a7b..b379146de55b 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -302,7 +302,6 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) advance = 0; printk(KERN_ERR "Couldn't emulate instruction 0x%08x " "(op %d xop %d)\n", inst, get_op(inst), get_xop(inst)); - kvmppc_core_queue_program(vcpu, 0); } } |