Re: r336921 broke booting on MBP 2017, EFIRT related

On Wed, Aug 29, 2018 at 8:20 AM Rainer Hurling <rhurlin_at_gwdg.de> wrote:
>
> Am 29.08.18 um 11:37 schrieb Yuri Pankov:
> > Hi,
> >
> > I've noticed that all recent snapshots (ALPHA3, ALPHA2, ALPHA1,
> > 20180802) fail to boot on MBP 2017:
> >
> > kbd0 at kbdmux0
> > netmap: loaded module
> > nexus0
> >
> > Fatal trap 12: page fault while in kernel mode
> > cpuid = 2: apic id = 02
> > fault virtual address  = 0x74c64a50
> > fault code             = supervisor read data, page not present
> > instruction pointer    = 0x20: 0x7abece31
> > stack pointer          = 0x28: 0xffffffff82b2f7c0
> > frame pointer          = 0x28: 0xffffffff82b2f810
> > code segment           = base 0x0, limit 0xfffff, type 0x1b
> >                        = DPL 0, pres 1, long 1, def32 0, gran 1
> > processor eflags       = interrupt enabled, resume, IOPL = 0
> > current process        = 0 (swapper)
> > [ thread pid 0 tid 100000 ]
> > Stopped at      0x7abece31:    calll   *0x18(%rax)
> > db>
> >
> > Sadly, there's no support for internal keyboard yet (it's connected via
> > SPI), and external USB one stops working.
> >
> > A (not so quick) bisect is pointing at r336921, which enabled EFIRT.
> >
> > Some questions here:
> > - is this something that can/should be fixed?
> > - can we print some "enabling EFIRT" message to the console to make
> >   guesses about the problem source a bit easier?
>
>
> I have almost exactly the same trap on a DELL Latitude E6520 with ALPHA3.

Hmm... that's a good data point. I might have a nearby Dell on-hand
with same firmware to reproduce with, then.

> Only _with_ 'OPTIONS EFIRT' enabled in the kernel _and_ deactivating it
> via efi.rt.disabled=1 in /boot/loader.conf, it works for me.
>
> An oddity is, that the spelling of the loader tuneable has to be
> efi.rt.disabled, not efi.rt_disabled (note the dot instead of an
> underscore!). The one with the underscore, as mentioned in UPDATING,
> does not work for me. Isn't this a typo somewhere in the code?
>

The UPDATING entry was later amended to reflect the new spelling
("efi.rt.disabled")

Thanks,

Kyle Evans