diff --git a/src/util/perf/u_trace.c b/src/util/perf/u_trace.c
index f2cad023328..7ee737748c8 100644
--- a/src/util/perf/u_trace.c
+++ b/src/util/perf/u_trace.c
@@ -887,11 +887,17 @@ u_trace_clone_append(struct u_trace_iterator begin_it,
       if (from_chunk == end_it.chunk)
          to_copy = MIN2(to_copy, end_it.event_idx - from_idx);
 
+      /* Reserve space in the chunk before emitting the copy as it could also
+       * add its own tracepoints.
+       */
+      unsigned to_chunk_idx = to_chunk->num_traces;
+      to_chunk->num_traces += to_copy;
+
       copy_buffer(begin_it.ut->utctx, cmdstream,
                   from_chunk->timestamps,
                   begin_it.ut->utctx->timestamp_size_bytes * from_idx,
                   to_chunk->timestamps,
-                  begin_it.ut->utctx->timestamp_size_bytes * to_chunk->num_traces,
+                  begin_it.ut->utctx->timestamp_size_bytes * to_chunk_idx,
                   begin_it.ut->utctx->timestamp_size_bytes * to_copy);
 
       if (from_chunk->has_indirect) {
@@ -899,11 +905,11 @@ u_trace_clone_append(struct u_trace_iterator begin_it,
                      from_chunk->indirects,
                      begin_it.ut->utctx->max_indirect_size_bytes * from_idx,
                      to_chunk->indirects,
-                     begin_it.ut->utctx->max_indirect_size_bytes * to_chunk->num_traces,
+                     begin_it.ut->utctx->max_indirect_size_bytes * to_chunk_idx,
                      begin_it.ut->utctx->max_indirect_size_bytes * to_copy);
       }
 
-      memcpy(&to_chunk->traces[to_chunk->num_traces],
+      memcpy(&to_chunk->traces[to_chunk_idx],
              &from_chunk->traces[from_idx],
              to_copy * sizeof(struct u_trace_event));
 
@@ -919,7 +925,6 @@ u_trace_clone_append(struct u_trace_iterator begin_it,
       }
 
       into->num_traces += to_copy;
-      to_chunk->num_traces += to_copy;
       from_idx += to_copy;
 
       assert(from_idx <= from_chunk->num_traces);