Comment 16 for bug 1625805

Revision history for this message
Paolo Pisati (p-pisati) wrote : Re: arm64 kernel panic for l2 mmu with unity8 session snap

Kevin, the oops above is just the history-daemon process that dereferences a stray pointer: i can reproduce it on every arm64 installation where i tried running the history-daemon (classic or snappy), or a test.c prg like the one below.

(here is my raspberrypi3 in arm64 mode dereferencing a foobar ptr)

$ cat test.c
int main(void) {

        ((void(*)(void))0x18)();
}

$ gcc test.c
$ ./a.out

dmesg:
...
[ 783.753484] a.out[447]: unhandled level 2 translation fault (11) at 0x00000018, esr 0x82000006
[ 783.753495] pgd = ffffffc037a7e000
[ 783.757090] [00000018] *pgd=0000000036fdd003, *pud=0000000036fdd003, *pmd=0000000000000000

[ 783.765693] CPU: 3 PID: 447 Comm: a.out Not tainted 4.8.0-1016-raspi2 #18~ufaultfd
[ 783.765698] Hardware name: Raspberry Pi 3 Model B Rev 1.2 (DT)
[ 783.765704] task: ffffffc036dc8000 task.stack: ffffffc0356e4000
[ 783.765711] PC is at 0x18
[ 783.765716] LR is at 0x400580
[ 783.765721] pc : [<0000000000000018>] lr : [<0000000000400580>] pstate: 60000000
[ 783.765725] sp : 0000007fc9fc7090
[ 783.765729] x29: 0000007fc9fc7090 x28: 0000000000000000
[ 783.765738] x27: 0000000000000000 x26: 0000000000000000
[ 783.765747] x25: 0000000000000000 x24: 0000000000000000
[ 783.765756] x23: 0000000000000000 x22: 0000000000000000
[ 783.765765] x21: 0000000000000000 x20: 0000000000000000
[ 783.765774] x19: 0000000000400590 x18: 0000000000000a03
[ 783.765783] x17: 0000000000411000 x16: 0000007f8ca7c7c0
[ 783.765792] x15: 0000007f8cbcf000 x14: 0000000000000000
[ 783.765801] x13: 0000000000000402 x12: 0000007f8cbd0028
[ 783.765810] x11: 0000000000000020 x10: 0101010101010101
[ 783.765819] x9 : 000000ffffffffff x8 : ffffffffffffffff
[ 783.765829] x7 : 0000000004000000 x6 : 0000000000000000
[ 783.765837] x5 : 0000000000000000 x4 : 0000007fc9fc7108
[ 783.765846] x3 : 0000000000400570 x2 : 0000007fc9fc71f8
[ 783.765855] x1 : 0000007fc9fc71e8 x0 : 0000000000000018

$ uname -a
Linux raspi64 4.8.0-1016-raspi2 #18 SMP Fri Oct 14 13:29:38 UTC 2016 aarch64 aarch64 aarch64 GNU/Linux