arm64 efi_power_off crash

[Geoff Levand]

Hi,

Got this with v4.0-rc6 and arm64 defconfig on the foundation
model and Linaro's 15.01 firmware when I do a 'poweroff'.
Didn't look into it.

-Geoff

reboot: Power down
Unable to handle kernel paging request at virtual address 1c0100a8
pgd = ffffffc079705000
[1c0100a8] *pgd=00000000f965e003, *pud=00000000f965e003, *pmd=0000000000000000
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 1050 Comm: halt Tainted: G        W       4.0.0-rc6 #1
Hardware name: ARM Arm Versatile Express/Arm Versatile Express, BIOS 09:51:17 Jan 27 2015
task: ffffffc87a076e00 ti: ffffffc0796a4000 task.ti: ffffffc0796a4000
PC is at 0x400f2674
LR is at 0x400f265c
pc : [<00000000400f2674>] lr : [<00000000400f265c>] pstate: 600001c5
sp : ffffffc0796a7c80
x29: ffffffc0796a7d10 x28: ffffffc0796a4000 
x27: ffffffc00056b000 x26: 000000000000008e 
x25: 000000000000011a x24: 0000000000000000 
x23: 0000000000000000 x22: 0000000000000000 
x21: 0000000000000008 x20: ffffffc0796a7cfc 
x19: 000000001c0100a8 x18: 0000000000000000 
x17: 0000007f9bd72b10 x16: ffffffc0000cdf94 
x15: 000000000000021e x14: 0000007f9bcb52b8 
x13: 000000000000021e x12: 0000000000412000 
x11: ffffffc0007a6000 x10: ffffffc0007ea000 
x9 : 0000000000000000 x8 : 0000000000000000 
x7 : ffffffc0007965d8 x6 : ffffffc000391b50 
x5 : ffffffc0796a7cfc x4 : 0000000000000000 
x3 : 0000000000000000 x2 : 0000000000000000 
x1 : 00000000fffffffe x0 : 000000001c0100a8 

Process halt (pid: 1050, stack limit = 0xffffffc0796a4028)
Stack: (0xffffffc0796a7c80 to 0xffffffc0796a8000)
7c80: 40000000 00000000 400f24e4 00000000 796a7d40 ffffffc0 fffffffe 00000000
7ca0: 00809c50 ffffffc0 000001c0 00000000 00000002 00000000 00000002 00000000
7cc0: fee1dead ffffffff 00000015 00000000 400f2634 00000000 000cdef8 ffffffc0
7ce0: 400f2480 00000000 0032562c ffffffc0 796a7d00 ffffffc0 000935b4 00000000
7d00: 00473614 ffffffc0 004735f0 ffffffc0 796a7d60 ffffffc0 00473538 ffffffc0
7d20: 00000000 00000000 4321fedc 00000000 007a3d88 ffffffc0 00090350 ffffffc0
7d40: 796a7d70 ffffffc0 00000000 00000000 00000000 00000000 00000000 00000000
7d60: 796a7d70 ffffffc0 00086a2c ffffffc0 796a7d80 ffffffc0 000cdf04 ffffffc0
7d80: 796a7d90 ffffffc0 000ce0e8 ffffffc0 d21faf10 0000007f 00085c30 ffffffc0
7da0: 00000000 00000000 d21fb0d8 0000007f ffffffff ffffffff 9bd72b2c 0000007f
7dc0: 00000000 00000000 00000015 00000000 796a7df0 ffffffc0 000befbc ffffffc0
7de0: 00000000 00000000 000befa4 00000000 d21faf10 0000007f 00085c30 ffffffc0
7e00: 00000000 00000000 d21fb0d8 0000007f ffffffff ffffffff 9bce4db8 0000007f
7e20: 80000000 00000000 00000015 00000000 0000011a 00000000 001945fc ffffffc0
7e40: 796a7e60 ffffffc0 00194584 ffffffc0 00000014 00000000 00000000 ffffffc0
7e60: 0000041a 00000000 00194634 ffffffc0 00000000 00000000 d21fb0d8 0000007f
7e80: ffffffff ffffffff 9bd6cf20 0000007f 796a7eb0 ffffffc0 00089604 ffffffc0
7ea0: 00000008 00000000 00024800 ffff0000 d21faf10 0000007f 00085b4c ffffffc0
7ec0: 00000000 00000000 00085c30 ffffffc0 fee1dead ffffffff 28121969 00000000
7ee0: 4321fedc 00000000 00000002 00000000 00000000 00000000 00000005 00000000
7f00: d21faf00 0000007f 9be1f000 0000007f 0000008e 00000000 00000000 00000000
7f20: 00000000 00000000 9be24cb0 0000007f 00412000 00000000 0000021e 00000000
7f40: 9bcb52b8 0000007f 0000021e 00000000 00412dd0 00000000 9bd72b10 0000007f
7f60: 00000000 00000000 00000000 00000000 d21fb0d8 0000007f 00000005 00000000
7f80: 004026b4 00000000 00000000 00000000 00412000 00000000 00000001 00000000
7fa0: 00000000 00000000 00000001 00000000 00000000 00000000 d21faf10 0000007f
7fc0: 00401714 00000000 d21faf10 0000007f 9bd72b2c 0000007f 00000000 00000000
7fe0: fee1dead ffffffff 0000008e 00000000 00000000 00000000 00000000 00000000
Call trace:
[<00000000400f2674>] 0x400f2674
[<ffffffc000473534>] efi_power_off+0x20/0x2c
[<ffffffc000086a28>] machine_power_off+0x1c/0x28
[<ffffffc0000cdf00>] kernel_power_off+0x60/0x6c
[<ffffffc0000ce0e4>] SyS_reboot+0x150/0x214
Code: aa1303e0 a9407bf3 910083ff 14000003 (b9400000) 
---[ end trace f890eacf6ac54c75 ]---
note: halt[1050] exited with preempt_count 3
/etc/rc0.d/S90halt: line 27:  1050 Segmentation fault      halt -d -f -p $hddown