From 367fe8aba192dc46bf8ac74d6576cfbd3e151912 Mon Sep 17 00:00:00 2001
From: Shailend Chand <shailend@google.com>
Date: Fri, 4 Sep 2026 16:02:18 -0700
Subject: [PATCH] cgroup2fs: Turn the cpuset mu into a lockdep mutex

PiperOrigin-RevId: 976537118
---
 pkg/sentry/fsimpl/cgroup2fs/BUILD     | 8 ++++++++
 pkg/sentry/fsimpl/cgroup2fs/cpuset.go | 3 +--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/pkg/sentry/fsimpl/cgroup2fs/BUILD b/pkg/sentry/fsimpl/cgroup2fs/BUILD
index 49a37e2e8e6..eda5f0ba810 100644
--- a/pkg/sentry/fsimpl/cgroup2fs/BUILD
+++ b/pkg/sentry/fsimpl/cgroup2fs/BUILD
@@ -14,6 +14,7 @@ go_library(
         "cpu.go",
         "cpu_mutex.go",
         "cpuset.go",
+        "cpuset_mutex.go",
         "event.go",
         "filesystem.go",
         "memory.go",
@@ -74,3 +75,10 @@ declare_mutex(
     package = "cgroup2fs",
     prefix = "cpu",
 )
+
+declare_mutex(
+    name = "cpuset_mutex",
+    out = "cpuset_mutex.go",
+    package = "cgroup2fs",
+    prefix = "cpuset",
+)
diff --git a/pkg/sentry/fsimpl/cgroup2fs/cpuset.go b/pkg/sentry/fsimpl/cgroup2fs/cpuset.go
index d2fafef8a9b..13e34389665 100644
--- a/pkg/sentry/fsimpl/cgroup2fs/cpuset.go
+++ b/pkg/sentry/fsimpl/cgroup2fs/cpuset.go
@@ -25,7 +25,6 @@ import (
 	"gvisor.dev/gvisor/pkg/hostarch"
 	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sentry/vfs"
-	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/usermem"
 )
 
@@ -35,7 +34,7 @@ type cpuset struct {
 	parent   *cpuset
 	detached atomicbitops.Bool
 
-	mu sync.Mutex `state:"nosave"`
+	mu cpusetMutex `state:"nosave"`
 
 	cpus *bitmap.Bitmap
 	mems *bitmap.Bitmap