Re: I'd like to donate a MacBook Pro

From: Alex Henrie
Date: Thu May 11 2017 - 16:21:43 EST


2017-05-11 5:16 GMT-06:00 Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>:
> Looks like there are a few people suffering from macbook xhci related issues
>
> From the bugs linked it looks like there are both some UEFI issues and a
> non-responsive
> usb device at boot. at least one USB device does not respond to a address
> device command,
> and driver times out and aborts the command after 5 second.
>
> I don't think I can do anything about the UEFI or the first 5 second command
> timeout
> from the xhci driver, but after that some improvement could be done.
>
> This timeout code path in the xhci driver is not exercised that often.
> Some minor races were fixed in 4.11 in this area, and better tracing added,
> but unfortunately
> I just discovered there is also has a regression in 4.11
>
> If you can help me debug this by compiling some new kernels and taking logs
> and traces on
> your MacBook we could get this forward.
>
> I set up a branch for this issue, it has the race-fixes, tracing and
> regression fixes:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git xhci-macbook
>
> Remember to check out the xhci-macbook branch.
>
> Can you compile and run that kernel on yout MacBook, and take logs?
>
> Traces can be enabled by adding "trace_event=xhci-hcd" to you kernel command
> line,
> then send me the output of both dmesg and /sys/kernel/debug/tracing/trace
> after the issue is seen.

Thanks for the detailed instructions. Your xhci-macbook branch works
just as well as Linux 4.10: The system boots up with a working
keyboard after a 2-minute delay. Unfortunately, I was not able to save
any logs because I couldn't figure out which kernel option would let
me access the encrypted hard drive. After putting in my password, I
got the error "crypt: unknown target type".

-Alex