Hi!

Hmm. Looks like there's a lot of fun to be had with sysfs.

								Pavel


pavel@n900:~$ uname -a
Linux n900 4.16.0-rc4-59690-g7f84626-dirty #543 Thu Mar 8 19:53:30 CET
2018 armv7l GNU/Linux

[  306.402496] bq2415x: command Timer reset
[  312.761322] adp1653 2-0030: Read Addr:03 Val:00 ok
[  313.264129] Unable to handle kernel NULL pointer dereference at
virtual address 00000
000
[  313.272308] pgd = 01336620
[  313.275146] [00000000] *pgd=800af831, *pte=00000000, *ppte=00000000
[  313.281463] Internal error: Oops: 80000007 [#1] ARM
[  313.286376] Modules linked in:
[  313.289459] CPU: 0 PID: 3584 Comm: grep Tainted: G        W
4.16.0-rc4-59690-g
7f84626-dirty #543
[  313.298919] Hardware name: Nokia RX-51 board
[  313.303222] PC is at   (null)
[  313.306213] LR is at iio_ev_state_show+0x38/0x54
[  313.310852] pc : [<00000000>]    lr : [<c05d69c0>]    psr: a0000013
[  313.317169] sp : c7b47e70  ip : c087bb24  fp : 00000001
[  313.322418] r10: cb19e000  r9 : c0857220  r8 : 00001000
[  313.327667] r7 : 00000fff  r6 : cb711c80  r5 : cb19e000  r4 :
00000000
[  313.334228] r3 : 00000001  r2 : 00000000  r1 : c087b4dc  r0 :
ce584800
[  313.340789] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM
Segment none
[  313.347991] Control: 10c5387d  Table: 87bec019  DAC: 00000051
[  313.353759] Process grep (pid: 3584, stack limit = 0xc4e45eab)
[  313.359619] Stack: (0xc7b47e70 to 0xc7b48000)
[  313.364013] 7e60:                                     c05d6988
cb711b00 ce585c00 c0450d68
[  313.471038] [<c05d69c0>] (iio_ev_state_show) from [<c0450d68>]
(dev_attr_show+0x1c/0x4c)
[  313.479187] [<c0450d68>] (dev_attr_show) from [<c023f934>]
(sysfs_kf_seq_show+0x90/0x108)
[  313.487426] [<c023f934>] (sysfs_kf_seq_show) from [<c023e2f8>]
(kernfs_seq_show+0x24/0x28)
[  313.495758] [<c023e2f8>] (kernfs_seq_show) from [<c01fc954>]
(seq_read+0x1dc/0x500)
[  313.503479] [<c01fc954>] (seq_read) from [<c01d9f80>]
(__vfs_read+0x2c/0x120)
[  313.510681] [<c01d9f80>] (__vfs_read) from [<c01da0fc>]
(vfs_read+0x88/0x114)
[  313.517852] [<c01da0fc>] (vfs_read) from [<c01da584>]
(SyS_read+0x40/0x8c)
[  313.524780] [<c01da584>] (SyS_read) from [<c0101000>]
(ret_fast_syscall+0x0/0x54)
[  313.532318] Exception stack(0xc7b47fa8 to 0xc7b47ff0)
[  313.537414] 7fa0:                   00035330 00042000 00000003
00042000 00008000 00008000


-- 
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