Re: [ 12/75] USB: EHCI: work around silicon bug in Intels EHCI controllers

Sven Joachim
2013-03-20T20:14:51Z

On 2013-03-20 21:08 +0100, Greg Kroah-Hartman wrote:

> On Tue, Mar 19, 2013 at 10:44:30PM +0100, Sven Joachim wrote:
>> On 2013-03-19 22:00 +0100, Alan Stern wrote:
>>
>> > On Tue, 19 Mar 2013, Sven Joachim wrote:
>> >
>> >> On 2013-03-19 21:10 +0100, Alan Stern wrote:
>> >>
>> >> > On Tue, 19 Mar 2013, Sven Joachim wrote:
>> >> >
>> >> >> > In what way is resume broken?
>> >> >>
>> >> >> The kernel comes back, but the screen is black. Manually switching VT's
>> >> >> is possible, and if I type something I can see it on the screen, but
>> >> >> there is no response and the cursor does not blink. It looks as if the
>> >> >> VT is not switched backed on resume, and userspace tasks are not
>> >> >> restarted. Sysrq combinations apparently work, but produce no output.
>> >> >
>> >> > Are there any other problems? For example, even before you do a
>> >> > suspend, if you type Alt-SysRq-W do you see any processes listed?
>> >>
>> >> No.
>> >>
>> >> > There was another report on the linux-usb mailing list today of this
>> >> > same patch causing the khubd task to hang. I'm thinking that you might
>> >> > be facing a similar problem.
>> >>
>> >> Maybe, but before the suspend everything seems to be normal.
>> >
>> > Just out of curiosity, does the patch posted here:
>> >
>> > http://marc.info/?l=linux-usb&m=136361874807411&w=2
>> >
>> > make any difference?
>>
>> It fixes the problem for me, thanks. :-)
>
> Ok, I'll postpone this patch for the next stable release, in time for
> the fix to be put in at the same time.

I think patch 13/75 ("USB: EHCI: dont check DMA values in QH overlays")
should also be postponed then, at least Alan said so in
<Pine.LNX.4.44L0.1303191125100.15684-100000@netrider.rowland.org>.

Cheers,
Sven