__u64 cookie_value;
 };
 
+static bool is_cgroup1;
+static int target_hid;
+
+#define CGROUP_MODE_SET(skel)                  \
+{                                              \
+       skel->bss->is_cgroup1 = is_cgroup1;     \
+       skel->bss->target_hid = target_hid;     \
+}
+
+static void cgroup_mode_value_init(bool cgroup, int hid)
+{
+       is_cgroup1 = cgroup;
+       target_hid = hid;
+}
+
 static void test_tp_btf(int cgroup_fd)
 {
        struct cgrp_ls_tp_btf *skel;
        if (!ASSERT_OK_PTR(skel, "skel_open_and_load"))
                return;
 
+       CGROUP_MODE_SET(skel);
+
        /* populate a value in map_b */
        err = bpf_map_update_elem(bpf_map__fd(skel->maps.map_b), &cgroup_fd, &val1, BPF_ANY);
        if (!ASSERT_OK(err, "map_update_elem"))
        if (!ASSERT_OK_PTR(skel, "skel_open_and_load"))
                return;
 
+       CGROUP_MODE_SET(skel);
+
        err = cgrp_ls_recursion__attach(skel);
        if (!ASSERT_OK(err, "skel_attach"))
                goto out;
        if (!ASSERT_OK_PTR(skel, "skel_open"))
                return;
 
+       CGROUP_MODE_SET(skel);
+
        bpf_program__set_autoload(skel->progs.cgroup_iter, true);
        err = cgrp_ls_sleepable__load(skel);
        if (!ASSERT_OK(err, "skel_load"))
        if (!ASSERT_OK_PTR(skel, "skel_open"))
                return;
 
+       CGROUP_MODE_SET(skel);
        skel->bss->target_pid = syscall(SYS_gettid);
 
        bpf_program__set_autoload(skel->progs.yes_rcu_lock, true);
        if (!ASSERT_OK_PTR(skel, "skel_open"))
                return;
 
+       CGROUP_MODE_SET(skel);
+
        bpf_program__set_autoload(skel->progs.no_rcu_lock, true);
        err = cgrp_ls_sleepable__load(skel);
        ASSERT_ERR(err, "skel_load");
        cgrp_ls_sleepable__destroy(skel);
 }
 
-void test_cgrp_local_storage(void)
+static void test_cgrp1_no_rcu_lock(void)
+{
+       struct cgrp_ls_sleepable *skel;
+       int err;
+
+       skel = cgrp_ls_sleepable__open();
+       if (!ASSERT_OK_PTR(skel, "skel_open"))
+               return;
+
+       CGROUP_MODE_SET(skel);
+
+       bpf_program__set_autoload(skel->progs.cgrp1_no_rcu_lock, true);
+       err = cgrp_ls_sleepable__load(skel);
+       ASSERT_OK(err, "skel_load");
+
+       cgrp_ls_sleepable__destroy(skel);
+}
+
+static void cgrp2_local_storage(void)
 {
        __u64 cgroup_id;
        int cgroup_fd;
        if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /cgrp_local_storage"))
                return;
 
+       cgroup_mode_value_init(0, -1);
+
        cgroup_id = get_cgroup_id("/cgrp_local_storage");
        if (test__start_subtest("tp_btf"))
                test_tp_btf(cgroup_fd);
 
        close(cgroup_fd);
 }
+
+static void cgrp1_local_storage(void)
+{
+       int cgrp1_fd, cgrp1_hid, cgrp1_id, err;
+
+       /* Setup cgroup1 hierarchy */
+       err = setup_classid_environment();
+       if (!ASSERT_OK(err, "setup_classid_environment"))
+               return;
+
+       err = join_classid();
+       if (!ASSERT_OK(err, "join_cgroup1"))
+               goto cleanup;
+
+       cgrp1_fd = open_classid();
+       if (!ASSERT_GE(cgrp1_fd, 0, "cgroup1 fd"))
+               goto cleanup;
+
+       cgrp1_id = get_classid_cgroup_id();
+       if (!ASSERT_GE(cgrp1_id, 0, "cgroup1 id"))
+               goto close_fd;
+
+       cgrp1_hid = get_cgroup1_hierarchy_id("net_cls");
+       if (!ASSERT_GE(cgrp1_hid, 0, "cgroup1 hid"))
+               goto close_fd;
+
+       cgroup_mode_value_init(1, cgrp1_hid);
+
+       if (test__start_subtest("cgrp1_tp_btf"))
+               test_tp_btf(cgrp1_fd);
+       if (test__start_subtest("cgrp1_recursion"))
+               test_recursion(cgrp1_fd);
+       if (test__start_subtest("cgrp1_negative"))
+               test_negative();
+       if (test__start_subtest("cgrp1_iter_sleepable"))
+               test_cgroup_iter_sleepable(cgrp1_fd, cgrp1_id);
+       if (test__start_subtest("cgrp1_yes_rcu_lock"))
+               test_yes_rcu_lock(cgrp1_id);
+       if (test__start_subtest("cgrp1_no_rcu_lock"))
+               test_cgrp1_no_rcu_lock();
+
+close_fd:
+       close(cgrp1_fd);
+cleanup:
+       cleanup_classid_environment();
+}
+
+void test_cgrp_local_storage(void)
+{
+       cgrp2_local_storage();
+       cgrp1_local_storage();
+}
 
        __type(value, long);
 } map_b SEC(".maps");
 
+int target_hid = 0;
+bool is_cgroup1 = 0;
+
+struct cgroup *bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id) __ksym;
+void bpf_cgroup_release(struct cgroup *cgrp) __ksym;
+
+static void __on_lookup(struct cgroup *cgrp)
+{
+       bpf_cgrp_storage_delete(&map_a, cgrp);
+       bpf_cgrp_storage_delete(&map_b, cgrp);
+}
+
 SEC("fentry/bpf_local_storage_lookup")
 int BPF_PROG(on_lookup)
 {
        struct task_struct *task = bpf_get_current_task_btf();
+       struct cgroup *cgrp;
+
+       if (is_cgroup1) {
+               cgrp = bpf_task_get_cgroup1(task, target_hid);
+               if (!cgrp)
+                       return 0;
 
-       bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp);
-       bpf_cgrp_storage_delete(&map_b, task->cgroups->dfl_cgrp);
+               __on_lookup(cgrp);
+               bpf_cgroup_release(cgrp);
+               return 0;
+       }
+
+       __on_lookup(task->cgroups->dfl_cgrp);
        return 0;
 }
 
-SEC("fentry/bpf_local_storage_update")
-int BPF_PROG(on_update)
+static void __on_update(struct cgroup *cgrp)
 {
-       struct task_struct *task = bpf_get_current_task_btf();
        long *ptr;
 
-       ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0,
-                                  BPF_LOCAL_STORAGE_GET_F_CREATE);
+       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE);
        if (ptr)
                *ptr += 1;
 
-       ptr = bpf_cgrp_storage_get(&map_b, task->cgroups->dfl_cgrp, 0,
-                                  BPF_LOCAL_STORAGE_GET_F_CREATE);
+       ptr = bpf_cgrp_storage_get(&map_b, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE);
        if (ptr)
                *ptr += 1;
+}
 
+SEC("fentry/bpf_local_storage_update")
+int BPF_PROG(on_update)
+{
+       struct task_struct *task = bpf_get_current_task_btf();
+       struct cgroup *cgrp;
+
+       if (is_cgroup1) {
+               cgrp = bpf_task_get_cgroup1(task, target_hid);
+               if (!cgrp)
+                       return 0;
+
+               __on_update(cgrp);
+               bpf_cgroup_release(cgrp);
+               return 0;
+       }
+
+       __on_update(task->cgroups->dfl_cgrp);
        return 0;
 }
 
-SEC("tp_btf/sys_enter")
-int BPF_PROG(on_enter, struct pt_regs *regs, long id)
+static void __on_enter(struct pt_regs *regs, long id, struct cgroup *cgrp)
 {
-       struct task_struct *task;
        long *ptr;
 
-       task = bpf_get_current_task_btf();
-       ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0,
-                                  BPF_LOCAL_STORAGE_GET_F_CREATE);
+       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE);
        if (ptr)
                *ptr = 200;
 
-       ptr = bpf_cgrp_storage_get(&map_b, task->cgroups->dfl_cgrp, 0,
-                                  BPF_LOCAL_STORAGE_GET_F_CREATE);
+       ptr = bpf_cgrp_storage_get(&map_b, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE);
        if (ptr)
                *ptr = 100;
+}
+
+SEC("tp_btf/sys_enter")
+int BPF_PROG(on_enter, struct pt_regs *regs, long id)
+{
+       struct task_struct *task = bpf_get_current_task_btf();
+       struct cgroup *cgrp;
+
+       if (is_cgroup1) {
+               cgrp = bpf_task_get_cgroup1(task, target_hid);
+               if (!cgrp)
+                       return 0;
+
+               __on_enter(regs, id, cgrp);
+               bpf_cgroup_release(cgrp);
+               return 0;
+       }
+
+       __on_enter(regs, id, task->cgroups->dfl_cgrp);
        return 0;
 }
 
 
 __u32 target_pid;
 __u64 cgroup_id;
+int target_hid;
+bool is_cgroup1;
 
+struct cgroup *bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id) __ksym;
+void bpf_cgroup_release(struct cgroup *cgrp) __ksym;
 void bpf_rcu_read_lock(void) __ksym;
 void bpf_rcu_read_unlock(void) __ksym;
 
        return 0;
 }
 
+static void __no_rcu_lock(struct cgroup *cgrp)
+{
+       long *ptr;
+
+       /* Note that trace rcu is held in sleepable prog, so we can use
+        * bpf_cgrp_storage_get() in sleepable prog.
+        */
+       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0,
+                                  BPF_LOCAL_STORAGE_GET_F_CREATE);
+       if (ptr)
+               cgroup_id = cgrp->kn->id;
+}
+
 SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
-int no_rcu_lock(void *ctx)
+int cgrp1_no_rcu_lock(void *ctx)
 {
        struct task_struct *task;
        struct cgroup *cgrp;
-       long *ptr;
+
+       task = bpf_get_current_task_btf();
+       if (task->pid != target_pid)
+               return 0;
+
+       /* bpf_task_get_cgroup1 can work in sleepable prog */
+       cgrp = bpf_task_get_cgroup1(task, target_hid);
+       if (!cgrp)
+               return 0;
+
+       __no_rcu_lock(cgrp);
+       bpf_cgroup_release(cgrp);
+       return 0;
+}
+
+SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
+int no_rcu_lock(void *ctx)
+{
+       struct task_struct *task;
 
        task = bpf_get_current_task_btf();
        if (task->pid != target_pid)
                return 0;
 
        /* task->cgroups is untrusted in sleepable prog outside of RCU CS */
-       cgrp = task->cgroups->dfl_cgrp;
-       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0,
-                                  BPF_LOCAL_STORAGE_GET_F_CREATE);
-       if (ptr)
-               cgroup_id = cgrp->kn->id;
+       __no_rcu_lock(task->cgroups->dfl_cgrp);
        return 0;
 }
 
        if (task->pid != target_pid)
                return 0;
 
+       if (is_cgroup1) {
+               bpf_rcu_read_lock();
+               cgrp = bpf_task_get_cgroup1(task, target_hid);
+               if (!cgrp) {
+                       bpf_rcu_read_unlock();
+                       return 0;
+               }
+
+               ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE);
+               if (ptr)
+                       cgroup_id = cgrp->kn->id;
+               bpf_cgroup_release(cgrp);
+               bpf_rcu_read_unlock();
+               return 0;
+       }
+
        bpf_rcu_read_lock();
        cgrp = task->cgroups->dfl_cgrp;
        /* cgrp is trusted under RCU CS */
 
 int mismatch_cnt = 0;
 int enter_cnt = 0;
 int exit_cnt = 0;
+int target_hid = 0;
+bool is_cgroup1 = 0;
 
-SEC("tp_btf/sys_enter")
-int BPF_PROG(on_enter, struct pt_regs *regs, long id)
+struct cgroup *bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id) __ksym;
+void bpf_cgroup_release(struct cgroup *cgrp) __ksym;
+
+static void __on_enter(struct pt_regs *regs, long id, struct cgroup *cgrp)
 {
-       struct task_struct *task;
        long *ptr;
        int err;
 
-       task = bpf_get_current_task_btf();
-       if (task->pid != target_pid)
-               return 0;
-
        /* populate value 0 */
-       ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0,
+       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0,
                                   BPF_LOCAL_STORAGE_GET_F_CREATE);
        if (!ptr)
-               return 0;
+               return;
 
        /* delete value 0 */
-       err = bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp);
+       err = bpf_cgrp_storage_delete(&map_a, cgrp);
        if (err)
-               return 0;
+               return;
 
        /* value is not available */
-       ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, 0);
+       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0, 0);
        if (ptr)
-               return 0;
+               return;
 
        /* re-populate the value */
-       ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0,
+       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0,
                                   BPF_LOCAL_STORAGE_GET_F_CREATE);
        if (!ptr)
-               return 0;
+               return;
        __sync_fetch_and_add(&enter_cnt, 1);
        *ptr = MAGIC_VALUE + enter_cnt;
-
-       return 0;
 }
 
-SEC("tp_btf/sys_exit")
-int BPF_PROG(on_exit, struct pt_regs *regs, long id)
+SEC("tp_btf/sys_enter")
+int BPF_PROG(on_enter, struct pt_regs *regs, long id)
 {
        struct task_struct *task;
-       long *ptr;
+       struct cgroup *cgrp;
 
        task = bpf_get_current_task_btf();
        if (task->pid != target_pid)
                return 0;
 
-       ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0,
+       if (is_cgroup1) {
+               cgrp = bpf_task_get_cgroup1(task, target_hid);
+               if (!cgrp)
+                       return 0;
+
+               __on_enter(regs, id, cgrp);
+               bpf_cgroup_release(cgrp);
+               return 0;
+       }
+
+       __on_enter(regs, id, task->cgroups->dfl_cgrp);
+       return 0;
+}
+
+static void __on_exit(struct pt_regs *regs, long id, struct cgroup *cgrp)
+{
+       long *ptr;
+
+       ptr = bpf_cgrp_storage_get(&map_a, cgrp, 0,
                                   BPF_LOCAL_STORAGE_GET_F_CREATE);
        if (!ptr)
-               return 0;
+               return;
 
        __sync_fetch_and_add(&exit_cnt, 1);
        if (*ptr != MAGIC_VALUE + exit_cnt)
                __sync_fetch_and_add(&mismatch_cnt, 1);
+}
+
+SEC("tp_btf/sys_exit")
+int BPF_PROG(on_exit, struct pt_regs *regs, long id)
+{
+       struct task_struct *task;
+       struct cgroup *cgrp;
+
+       task = bpf_get_current_task_btf();
+       if (task->pid != target_pid)
+               return 0;
+
+       if (is_cgroup1) {
+               cgrp = bpf_task_get_cgroup1(task, target_hid);
+               if (!cgrp)
+                       return 0;
+
+               __on_exit(regs, id, cgrp);
+               bpf_cgroup_release(cgrp);
+               return 0;
+       }
+
+       __on_exit(regs, id, task->cgroups->dfl_cgrp);
        return 0;
 }