Adjust runtime schedt.nmspinning offset for go1.26

https://go.dev/cl/714800 changes the size of schedt.midle.

PiperOrigin-RevId: 831765475

Author: gvisor-bot

pkg/sync/runtime_spinning_amd64.s

@@ -13,7 +13,8 @@
 // limitations under the License.
 
 // https://go.dev/cl/669235 (1.25) adds a new schedt field prior to nmspinning.
-//go:build amd64 && !go1.25
+// https://go.dev/cl/714800 (1.26) changes size of the schedt.midle field.
+//go:build amd64 && !go1.25 && !go1.26
 
 #include "textflag.h"
 

pkg/sync/runtime_spinning_go125_amd64.s

@@ -13,7 +13,8 @@
 // limitations under the License.
 
 // https://go.dev/cl/669235 (1.25) adds a new schedt field prior to nmspinning.
-//go:build amd64 && go1.25
+// https://go.dev/cl/714800 (1.26) changes size of the schedt.midle field.
+//go:build amd64 && go1.25 && !go1.26
 
 #include "textflag.h"
 

pkg/sync/runtime_spinning_go126_amd64.s

@@ -0,0 +1,28 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// https://go.dev/cl/669235 (1.25) adds a new schedt field prior to nmspinning.
+// https://go.dev/cl/714800 (1.26) changes size of the schedt.midle field.
+//go:build amd64 && go1.25 && lgo1.26
+
+
+#include "textflag.h"
+
+#define NMSPINNING_OFFSET 116 // +checkoffset runtime schedt.nmspinning
+
+TEXT ·addrOfSpinning(SB),NOSPLIT|NOFRAME,$0-8
+	LEAQ runtime·sched(SB), AX
+	ADDQ $NMSPINNING_OFFSET, AX
+	MOVQ AX, ret+0(FP)
+	RET