Hi Christophe,

quoted

@@ -101,14 +129,20 @@ static bool is_ptrace_bp(struct perf_event *bp)

   */
  void arch_unregister_hw_breakpoint(struct perf_event *bp)
  {
+    int i;
+

This declaration should be in the block using it.

quoted

      /*
       * If the breakpoint is unregistered between a hw_breakpoint_handler()
       * and the single_step_dabr_instruction(), then cleanup the breakpoint
       * restoration variables to prevent dangling pointers.
       * FIXME, this should not be using bp->ctx at all! Sayeth peterz.
       */
-    if (bp->ctx && bp->ctx->task && bp->ctx->task != ((void *)-1L))
-        bp->ctx->task->thread.last_hit_ubp = NULL;
+    if (bp->ctx && bp->ctx->task && bp->ctx->task != ((void *)-1L)) {

Add declaration of 'int i' here.

How will that help? Keeping declaration at the start of function is also
common practice and I don't see any recommendation to move them inside
conditional block.

Thanks,
Ravi