KVM: PPC: Book3S PR: Add emulation for tabort. in privileged state
Currently privileged-state guest will be run with TM disabled.
Although the privileged-state guest cannot initiate a new transaction,
it can use tabort to terminate its problem state's transaction.
So it is still necessary to emulate tabort. for privileged-state guest.
Tested with:
https://github.com/justdoitqd/publicFiles/blob/master/test_tabort.c
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c
index b7530cf..34f910e 100644
--- a/arch/powerpc/kvm/book3s_emulate.c
+++ b/arch/powerpc/kvm/book3s_emulate.c
@@ -50,6 +50,7 @@
#define OP_31_XOP_SLBMFEE 915
#define OP_31_XOP_TBEGIN 654
+#define OP_31_XOP_TABORT 910
#define OP_31_XOP_TRECLAIM 942
#define OP_31_XOP_TRCHKPT 1006
@@ -196,6 +197,47 @@
kvmppc_restore_tm_pr(vcpu);
preempt_enable();
}
+
+/* emulate tabort. at guest privilege state */
+static void kvmppc_emulate_tabort(struct kvm_vcpu *vcpu, int ra_val)
+{
+ /* currently we only emulate tabort. but no emulation of other
+ * tabort variants since there is no kernel usage of them at
+ * present.
+ */
+ unsigned long guest_msr = kvmppc_get_msr(vcpu);
+
+ preempt_disable();
+ tm_enable();
+ tm_abort(ra_val);
+
+ /* CR0 = 0 | MSR[TS] | 0 */
+ vcpu->arch.cr = (vcpu->arch.cr & ~(CR0_MASK << CR0_SHIFT)) |
+ (((guest_msr & MSR_TS_MASK) >> (MSR_TS_S_LG - 1))
+ << CR0_SHIFT);
+
+ vcpu->arch.texasr = mfspr(SPRN_TEXASR);
+ /* failure recording depends on Failure Summary bit,
+ * and tabort will be treated as nops in non-transactional
+ * state.
+ */
+ if (!(vcpu->arch.texasr & TEXASR_FS) &&
+ MSR_TM_ACTIVE(guest_msr)) {
+ vcpu->arch.texasr &= ~(TEXASR_PR | TEXASR_HV);
+ if (guest_msr & MSR_PR)
+ vcpu->arch.texasr |= TEXASR_PR;
+
+ if (guest_msr & MSR_HV)
+ vcpu->arch.texasr |= TEXASR_HV;
+
+ vcpu->arch.tfiar = kvmppc_get_pc(vcpu);
+ mtspr(SPRN_TEXASR, vcpu->arch.texasr);
+ mtspr(SPRN_TFIAR, vcpu->arch.tfiar);
+ }
+ tm_disable();
+ preempt_enable();
+}
+
#endif
int kvmppc_core_emulate_op_pr(struct kvm_run *run, struct kvm_vcpu *vcpu,
@@ -468,6 +510,32 @@
emulated = EMULATE_FAIL;
break;
}
+ case OP_31_XOP_TABORT:
+ {
+ ulong guest_msr = kvmppc_get_msr(vcpu);
+ unsigned long ra_val = 0;
+
+ if (!cpu_has_feature(CPU_FTR_TM))
+ break;
+
+ if (!(kvmppc_get_msr(vcpu) & MSR_TM)) {
+ kvmppc_trigger_fac_interrupt(vcpu, FSCR_TM_LG);
+ emulated = EMULATE_AGAIN;
+ break;
+ }
+
+ /* only emulate for privilege guest, since problem state
+ * guest can run with TM enabled and we don't expect to
+ * trap at here for that case.
+ */
+ WARN_ON(guest_msr & MSR_PR);
+
+ if (ra)
+ ra_val = kvmppc_get_gpr(vcpu, ra);
+
+ kvmppc_emulate_tabort(vcpu, ra_val);
+ break;
+ }
case OP_31_XOP_TRECLAIM:
{
ulong guest_msr = kvmppc_get_msr(vcpu);