r0 = openat(0xffffffffffffff9c, &(0x7f0000000040)='./cgroup/cgroup.procs\x00', 0x2, 0x0)
mount$9p_fd(0x0, &(0x7f0000000000)='./cgroup/cgroup.procs\x00', &(0x7f00000000c0), 0x0, &(0x7f0000000100)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r0}})