src/internal/trace/v2/order.go                          |  7 +++++++
 src/internal/trace/v2/testdata/testprog/wait-on-pipe.go | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/internal/trace/v2/trace_test.go                     |  9 +++++++++
 src/runtime/trace2.go                                   |  2 +-

diff --git a/src/internal/trace/v2/order.go b/src/internal/trace/v2/order.go
index 24da41a35e1951918c74f0ae4e130a49f3bc1314..cedb29726ec339b2f13e379dc627e166b19b03a8 100644
--- a/src/internal/trace/v2/order.go
+++ b/src/internal/trace/v2/order.go
@@ -302,6 +302,13 @@ 			// Is the syscall on this thread? If so, bind it to the context.
 			// Otherwise, we're talking about a G sitting in a syscall on an M.
 			// Validate the named M.
 			if mid == curCtx.M {
+				if gen != o.initialGen && curCtx.G != gid {
+					// If this isn't the first generation, we *must* have seen this
+					// binding occur already. Even if the G was blocked in a syscall
+					// for multiple generations since trace start, we would have seen
+					// a previous GoStatus event that bound the goroutine to an M.
+					return curCtx, false, fmt.Errorf("inconsistent thread for syscalling goroutine %d: thread has goroutine %d", gid, curCtx.G)
+				}
 				newCtx.G = gid
 				break
 			}
diff --git a/src/internal/trace/v2/testdata/testprog/wait-on-pipe.go b/src/internal/trace/v2/testdata/testprog/wait-on-pipe.go
new file mode 100644
index 0000000000000000000000000000000000000000..912f5dd3bcae62a97532039bc8140356b62dfc3d
--- /dev/null
+++ b/src/internal/trace/v2/testdata/testprog/wait-on-pipe.go
@@ -0,0 +1,66 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Tests a goroutine sitting blocked in a syscall for
+// an entire generation. This is a regression test for
+// #65196.
+
+//go:build ignore
+
+package main
+
+import (
+	"log"
+	"os"
+	"runtime/trace"
+	"syscall"
+	"time"
+)
+
+func main() {
+	// Create a pipe to block on.
+	var p [2]int
+	if err := syscall.Pipe(p[:]); err != nil {
+		log.Fatalf("failed to create pipe: %v", err)
+	}
+	rfd, wfd := p[0], p[1]
+
+	// Create a goroutine that blocks on the pipe.
+	done := make(chan struct{})
+	go func() {
+		var data [1]byte
+		_, err := syscall.Read(rfd, data[:])
+		if err != nil {
+			log.Fatalf("failed to read from pipe: %v", err)
+		}
+		done <- struct{}{}
+	}()
+
+	// Give the goroutine ample chance to block on the pipe.
+	time.Sleep(10 * time.Millisecond)
+
+	// Start tracing.
+	if err := trace.Start(os.Stdout); err != nil {
+		log.Fatalf("failed to start tracing: %v", err)
+	}
+
+	// This isn't enough to have a full generation pass by default,
+	// but it is generally enough in stress mode.
+	time.Sleep(100 * time.Millisecond)
+
+	// Write to the pipe to unblock it.
+	if _, err := syscall.Write(wfd, []byte{10}); err != nil {
+		log.Fatalf("failed to write to pipe: %v", err)
+	}
+
+	// Wait for the goroutine to unblock and start running.
+	// This is helpful to catch incorrect information written
+	// down for the syscall-blocked goroutine, since it'll start
+	// executing, and that execution information will be
+	// inconsistent.
+	<-done
+
+	// Stop tracing.
+	trace.Stop()
+}
diff --git a/src/internal/trace/v2/trace_test.go b/src/internal/trace/v2/trace_test.go
index 3300c00fe80945df3e83ea207dbb1814567eaed0..65ae3d8362d8ee7486874fc7b06c0272e747589b 100644
--- a/src/internal/trace/v2/trace_test.go
+++ b/src/internal/trace/v2/trace_test.go
@@ -521,6 +521,15 @@ func TestTraceManyStartStop(t *testing.T) {
 	testTraceProg(t, "many-start-stop.go", nil)
 }
 
+func TestTraceWaitOnPipe(t *testing.T) {
+	switch runtime.GOOS {
+	case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
+		testTraceProg(t, "wait-on-pipe.go", nil)
+		return
+	}
+	t.Skip("no applicable syscall.Pipe on " + runtime.GOOS)
+}
+
 func testTraceProg(t *testing.T, progName string, extra func(t *testing.T, trace, stderr []byte, stress bool)) {
 	testenv.MustHaveGoRun(t)
 
diff --git a/src/runtime/trace2.go b/src/runtime/trace2.go
index 5fd09ed1eabf375cbb40561b55433bfae3314641..00ba081b4f4d0829509ab9f111c17dd2d82b32f3 100644
--- a/src/runtime/trace2.go
+++ b/src/runtime/trace2.go
@@ -334,7 +334,7 @@ 			s := suspendG(gp)
 			if !s.dead {
 				ug.goid = s.g.goid
 				if s.g.m != nil {
-					ug.mid = s.g.m.id
+					ug.mid = int64(s.g.m.procid)
 				}
 				ug.status = readgstatus(s.g) &^ _Gscan
 				ug.waitreason = s.g.waitreason