Comment 6 for bug 1469218

For #5's log, the fault happened in the following code snippet of kernel/sched/cputime.c:

                for_each_thread(tsk, t) {
ffffffc0000d3dc0: f9445760 ldr x0, [x27,#2216]
ffffffc0000d3dc4: f8410c03 ldr x3, [x0,#16]!
ffffffc0000d3dc8: f90037a3 str x3, [x29,#104]
ffffffc0000d3dcc: f94037b4 ldr x20, [x29,#104]
ffffffc0000d3dd0: eb00029f cmp x20, x0
ffffffc0000d3dd4: d10ee294 sub x20, x20, #0x3b8
ffffffc0000d3dd8: 54000081 b.ne ffffffc0000d3de8 <thread_group_cputime+0x90>
ffffffc0000d3ddc: 14000015 b ffffffc0000d3e30 <thread_group_cputime+0xd8>
ffffffc0000d3de0: f9400261 ldr x1, [x19]
ffffffc0000d3de4: f9400662 ldr x2, [x19,#8]
                                cputime_t *utime, cputime_t *stime)
{
        if (utime)
                *utime = t->utime;
        if (stime)
                *stime = t->stime;
ffffffc0000d3de8: f941f684 ldr x4, [x20,#1000] #fault instruction