While chasing a regression I noticed we potentially patch the wrong
code in native_patch().

If we do not select the native code sequence, we must use the default
patcher, not fall-through the switch case.

Fixes: 3cded4179481 ("x86/paravirt: Optimize native 
pv_lock_ops.vcpu_is_preempted()")
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
---
 arch/x86/kernel/paravirt_patch_32.c |    4 ++++
 arch/x86/kernel/paravirt_patch_64.c |    4 ++++
 2 files changed, 8 insertions(+)

--- a/arch/x86/kernel/paravirt_patch_32.c
+++ b/arch/x86/kernel/paravirt_patch_32.c
@@ -56,15 +56,19 @@ unsigned native_patch(u8 type, u16 clobb
                                end   = end_pv_lock_ops_queued_spin_unlock;
                                goto patch_site;
                        }
+                       goto patch_default;
+
                case PARAVIRT_PATCH(pv_lock_ops.vcpu_is_preempted):
                        if (pv_is_native_vcpu_is_preempted()) {
                                start = start_pv_lock_ops_vcpu_is_preempted;
                                end   = end_pv_lock_ops_vcpu_is_preempted;
                                goto patch_site;
                        }
+                       goto patch_default;
 #endif
 
        default:
+patch_default:
                ret = paravirt_patch_default(type, clobbers, ibuf, addr, len);
                break;
 
--- a/arch/x86/kernel/paravirt_patch_64.c
+++ b/arch/x86/kernel/paravirt_patch_64.c
@@ -68,15 +68,19 @@ unsigned native_patch(u8 type, u16 clobb
                                end   = end_pv_lock_ops_queued_spin_unlock;
                                goto patch_site;
                        }
+                       goto patch_default;
+
                case PARAVIRT_PATCH(pv_lock_ops.vcpu_is_preempted):
                        if (pv_is_native_vcpu_is_preempted()) {
                                start = start_pv_lock_ops_vcpu_is_preempted;
                                end   = end_pv_lock_ops_vcpu_is_preempted;
                                goto patch_site;
                        }
+                       goto patch_default;
 #endif
 
        default:
+patch_default:
                ret = paravirt_patch_default(type, clobbers, ibuf, addr, len);
                break;
 



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