Messages in this thread | | | Date | Thu, 6 Nov 2014 18:04:56 +0100 | From | Johan Hovold <> | Subject | Re: [3.16.1 BISECTED REGRESSION]: Simtec Entropy Key (cdc-acm) broken in 3.16 |
| |
On Thu, Nov 06, 2014 at 01:49:13PM +0000, Nix wrote: > On 5 Nov 2014, Johan Hovold told this: > > On Wed, Nov 05, 2014 at 03:14:49PM +0000, Nix wrote:
> > Could you try two more things (too make sure line control is really the > > culprit): > > > > 1. If you clear HUPCL in ekeyd so that the lines are never lowered, does > > that fix the stability issue? > > Definitely not. I got a hang after the first reboot out of an afflicted > kernel, when using a HUPCLless ekeyd. Weird. (I guess they're lowered on > reboot anyway?)
It's actually only the timings related to the control-lines being raised on open that has changed, so this would seem consistent with that.
> > 2. Can you verify that the patch below works? Did I use the correct > > VID/PID? Could you provide "lsusb -v" output (for the capability flags) > > as well? > > The VID/PID are right. > > The patch seems to work. I tested against the usb testing tree directly, > since that was easier than adjusting it to apply against 3.16. Sixteen > reboots, no failures, looks to be fixed.
Great, thanks for testing.
> > Note that the patch is against the usb-linus branch of the usb tree, > > OK. (I presume this is gregkh's tree, not yours?)
Yes, Greg's tree, could have been more clear about that.
> > which also contains another fix which could affect this device > > (set_termios will now be called an extra time on every open). You also > > need this one, which have not yet been applied: > > > > http://marc.info/?l=linux-usb&m=141520959813505&w=2 > > It had been applied by the time I tested this :)
Greg is fast. :)
Thanks for tracking this down. That bisect cannot have been fun given the low failure rate (sometimes only one in ten reboots?).
Johan
| |