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| author | Mihai Caraman <mihai.caraman@freescale.com> | 2014-07-23 19:06:21 +0300 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2014-07-28 15:23:14 +0200 |
| commit | 51f047261e717b74b226f837a16455994b61ae30 (patch) | |
| tree | e94a57703fed176a72acef425cea442a8395746b /arch/powerpc/kvm/emulate.c | |
| parent | 9a26af64d6bba72c9dfd62cc0cab0e79f8a66d7b (diff) | |
| download | blackbird-obmc-linux-51f047261e717b74b226f837a16455994b61ae30.tar.gz blackbird-obmc-linux-51f047261e717b74b226f837a16455994b61ae30.zip | |
KVM: PPC: Allow kvmppc_get_last_inst() to fail
On book3e, guest last instruction is read on the exit path using load
external pid (lwepx) dedicated instruction. This load operation may fail
due to TLB eviction and execute-but-not-read entries.
This patch lay down the path for an alternative solution to read the guest
last instruction, by allowing kvmppc_get_lat_inst() function to fail.
Architecture specific implmentations of kvmppc_load_last_inst() may read
last guest instruction and instruct the emulation layer to re-execute the
guest in case of failure.
Make kvmppc_get_last_inst() definition common between architectures.
Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'arch/powerpc/kvm/emulate.c')
| -rw-r--r-- | arch/powerpc/kvm/emulate.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index da86d9ba3476..c5c64b6e7eb2 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -224,19 +224,25 @@ static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) * from opcode tables in the future. */ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) { - u32 inst = kvmppc_get_last_inst(vcpu); - int ra = get_ra(inst); - int rs = get_rs(inst); - int rt = get_rt(inst); - int sprn = get_sprn(inst); - enum emulation_result emulated = EMULATE_DONE; + u32 inst; + int ra, rs, rt, sprn; + enum emulation_result emulated; int advance = 1; /* this default type might be overwritten by subcategories */ kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS); + emulated = kvmppc_get_last_inst(vcpu, false, &inst); + if (emulated != EMULATE_DONE) + return emulated; + pr_debug("Emulating opcode %d / %d\n", get_op(inst), get_xop(inst)); + ra = get_ra(inst); + rs = get_rs(inst); + rt = get_rt(inst); + sprn = get_sprn(inst); + switch (get_op(inst)) { case OP_TRAP: #ifdef CONFIG_PPC_BOOK3S |
