On Tue, May 17, 2016 at 10:01:37PM -0700, Florian Fainelli wrote:

Le 17/05/2016 21:37, Guenter Roeck a écrit :

quoted

Hi,

my xtensa qemu tests crash in -next as follows.

[ ... ]

[    9.366256] libphy: ethoc-mdio: probed
[    9.367389]  (null): could not attach to PHY
[    9.368555]  (null): failed to probe MDIO bus
[    9.371540] Unable to handle kernel paging request at virtual address
0000001c
[    9.371540]  pc = d0320926, ra = 903209d1
[    9.375358] Oops: sig: 11 [#1]
[    9.376081] PREEMPT
[    9.377080] CPU: 0 PID: 1 Comm: swapper Not tainted
4.6.0-next-20160517 #1
[    9.378397] task: d7c2c000 ti: d7c30000 task.ti: d7c30000
[    9.379394] a00: 903209d1 d7c31bd0 d7fb5810 00000001 00000000
00000000 d7f45c00 d7c31bd0
[    9.382298] a08: 00000000 00000000 00000000 00000000 00060100
d04b0c10 d7f45dfc d7c31bb0
[    9.385732] pc: d0320926, ps: 00060110, depc: 00000018, excvaddr:
0000001c
[    9.387061] lbeg: d0322e35, lend: d0322e57 lcount: 00000000, sar:
00000011
[    9.388173]
Stack: d7c31be0 00060700 d7f45c00 d7c31bd0 9021d509 d7c31c30 d7f45c00
00000000
       d0485dcc d0485dcc d7fb5810 d7c2c000 00000000 d7c31c30 d7f45c00
d025befc
       d0485dcc d7c30000 d7f45c34 d7c31bf0 9021c985 d7c31c50 d7f45c00
d7f45c34
[    9.396652] Call Trace:
[    9.397469]  [<d021d4d9>] __device_release_driver+0x7d/0x98
[    9.398869]  [<d021d509>] device_release_driver+0x15/0x20
[    9.400247]  [<d021c985>] bus_remove_device+0xc1/0xd4
[    9.401569]  [<d021a935>] device_del+0x109/0x15c
[    9.402794]  [<d025c3f9>] phy_mdio_device_remove+0xd/0x18
[    9.404124]  [<d025d264>] mdiobus_unregister+0x40/0x5c
[    9.405444]  [<d025ff44>] ethoc_probe+0x534/0x5b8
[    9.406742]  [<d021e2e0>] platform_drv_probe+0x28/0x48
[    9.408122]  [<d021d1e5>] driver_probe_device+0x101/0x234
[    9.409499]  [<d021d395>] __driver_attach+0x7d/0x98
[    9.410809]  [<d021bd80>] bus_for_each_dev+0x30/0x5c
[    9.412104]  [<d021cdf0>] driver_attach+0x14/0x18
[    9.413385]  [<d021ca61>] bus_add_driver+0xc9/0x198
[    9.414686]  [<d021d7d4>] driver_register+0x70/0xa0
[    9.416001]  [<d021e2b4>] __platform_driver_register+0x24/0x28
[    9.417463]  [<d04a1d34>] ethoc_driver_init+0x10/0x14
[    9.418824]  [<d00032c8>] do_one_initcall+0x80/0x1ac
[    9.420083]  [<d049386d>] kernel_init_freeable+0x131/0x198
[    9.421504]  [<d03236e8>] kernel_init+0xc/0xb0
[    9.422693]  [<d000482c>] ret_from_kernel_thread+0x8/0xc

Bisect points to commit da47b4572056 ("phy: add support for a reset-gpio
specification").
Bisect log is attached. Reverting the patch fixes the problem.

Aside from what you pointed out, this patch was still in dicussion when
it got merged, since we got a concurrent patch from Sergei which tries
to deal with the same kind of problem.

Do you mind sending a revert, or I can do that first thing in the morning.

I don't think I'll find the time to do that today, and also I would like
to hear from Dave what his preferences are.

Note that this now also affects mainline.

Guenter