Re: [BUG] ohci_enable() fails during resume

[Clemens Ladisch <clemens@ladisch.de>]

Lukasz Stelmach wrote:
> A bit, suddenly by desktop PC started to fail to resume. [...]
> The failing code is somewhere around line 2400 of
> drivers/firewire/ohci.c (the latest mainline).

>    0x000000000000003f <+31>: callq  0xffffffffffffb037 <copy_config_rom>
>    0x0000000000000044 <+36>: mov    0x898(%rbx),%rax
> -->0x000000000000004b <+43>: mov    (%rax),%edx       <--

(The copy_config_rom call was not actually executed; the else branch
jumped to 44.)

ohci->next_config_rom is NULL because ohci->config_rom is NULL.

> The code around the line 2400 appears to handle multiple
> firewire ports (if I recognise variable names correctly, e.g.
> next_config_rom).

No, this code handles multiple versions of the same data structure.

> Hardware bug in the on-board firewire controller *and* a bug in the
> driver.

Indeed; this appears to be the culprit:
> [  232.855042] firewire_ohci 0000:04:03.0: added OHCI v1.0 device as card 0, 8 IR + 8 IT contexts, quirks 0x0
> [  232.864724] firewire_ohci 0000:04:03.0: bad self ID 0/1 (00000000 != ~00000000)

With the "bad self ID", bus_reset_work() just aborts, and the controller
is never completely initialized (therefore the unexpected NULL).

Try unloading and reloading the firewire-ohci module to see if you can
ever avoid the "bad self ID" error.  But if it stays, your hardware
indeed appears to be broken.


Regards,
Clemens