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BUG: KMSAN: uninit-value in mpol_rebind_task+0x2ad/0x2c0
 mpol_rebind_task+0x2ad/0x2c0
 cpuset_attach+0x78b/0x15e0
 cgroup_migrate_execute+0x103c/0x1d50
 cgroup_attach_task+0x544/0x8b0
 __cgroup1_procs_write+0x5f6/0x7e0
 cgroup1_tasks_write+0x98/0xb0
 cgroup_file_write+0x4d7/0xa00
 kernfs_fop_write_iter+0x5ea/0x990
 vfs_write+0x10ab/0x1d40
 ksys_write+0x28f/0x510
 __x64_sys_write+0xdb/0x120
 do_syscall_64+0x3d/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
 kmem_cache_alloc+0xae6/0x1170
 do_set_mempolicy+0x43a/0xf90
 __x64_sys_set_mempolicy+0x3c3/0x430
 do_syscall_64+0x3d/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 1 PID: 16429 Comm: syz-executor.3 Not tainted 5.18.0-syzkaller-16253-g2f3064574275 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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