Re: git: bcd763b642ab - main - Move the arm64 DMAP creation to C

From: Kyle Evans <kevans_at_freebsd.org>
Date: Sat, 09 Apr 2022 05:44:55 UTC
On Sat, Apr 9, 2022 at 12:43 AM Kyle Evans <kevans@freebsd.org> wrote:
>
> On Sat, Apr 9, 2022 at 12:31 AM Kyle Evans <kevans@freebsd.org> wrote:
> >
> > On Wed, Apr 6, 2022 at 8:24 AM Andrew Turner <andrew@freebsd.org> wrote:
> > >
> > > The branch main has been updated by andrew:
> > >
> > > URL: https://cgit.FreeBSD.org/src/commit/?id=bcd763b642abb4b236902e84184c579225265fb7
> > >
> > > commit bcd763b642abb4b236902e84184c579225265fb7
> > > Author:     Andrew Turner <andrew@FreeBSD.org>
> > > AuthorDate: 2022-03-15 17:05:48 +0000
> > > Commit:     Andrew Turner <andrew@FreeBSD.org>
> > > CommitDate: 2022-04-06 13:09:49 +0000
> > >
> > >     Move the arm64 DMAP creation to C
> > >
> > >     To simplify the creation of the direct map (DMAP) region on arm64 move
> > >     it from the pre-C code into pmap. This simplifies the DMAP creation
> > >     as we can use the notmal index macros, and should reduce the number
> > >     of pages needed to hold the level 1 tables to just those needed.
> > >
> > >     Reviewed by:    alc, dch
> > >     Tested by:      dch, kevans
> > >     Sponsored by:   The FreeBSD Foundation
> > >     Differential Revision: https://reviews.freebsd.org/D34568
> >
> > Our Ampere boxes were fine with this, but this seems to tickle
> > something on this M1 mini that I have. Specifically, we end up dying
> > while probing UEFI stuff, here:
> >
> > https://cgit.freebsd.org/src/tree/sys/dev/efidev/efirt.c#n183
> >
> > efi_systbl_phys == 0x9e0979f30, efi_systbl == 0xffffa001e0979f30
> > Fatal data abort:
> > ...
> >   sp: ffff000000fb79b0
> >   lr: ffff000000157ae0 (efirt_modevents + 94)
> >  elr: ffff000000157ae8 (efirt_modevents + 9c)
> > spsr:         604000c5
> >  far: ffffa001e0979f30
> >  esr:         96000007
> > panic: vm_fault failed: ffff000000157ae8 error 1
> > cpuid = 0
> > time = 1
> > KDB: stack backtrace:
> > db_trace_self() at db_trace_self
> > db_trace_self_wrapper() at db_trace_self_wrapper+0x30
> > vpanic() at vpanic+0x174
> > panic() at panic+0x44
> > data_abort() at data_abort+0x2f0
> > handle_el1h_sync() at handle_el1h_sync+0x10
> > --- exception, esr 0x96000007
> > efirt_modevents() at efirt_modevents+0x9c
> > module_register_init() at module_register_init+0xc4
> > mi_startup() at mi_startup+0x284
> > virtdone() at virtdone+0x7c
>
> Er, maybe helpful:
>
> Physical memory chunk(s):
>   0x8010a8000 - 0x803ecbfff,    46 MB (  11812 pages)
>   0x803f8c000 - 0x8053e7fff,    20 MB (   5212 pages)
>   0x805402000 - 0x808f99fff,    59 MB (  15256 pages)
>   0x808fb6000 - 0x80d5fffff,    70 MB (  17994 pages)
>   0x80dc73000 - 0x9e096ffff,  7468 MB (1912061 pages)
>   0x9e0980000 - 0x9e0a33fff,     0 MB (    180 pages)
Excluded memory regions:
  0x803ecc000 - 0x803f8bfff,     0 MB (    192 pages) NoAlloc
  0x8053e8000 - 0x805401fff,     0 MB (     26 pages) NoAlloc
  0x808f9a000 - 0x808fb5fff,     0 MB (     28 pages) NoAlloc
  0x80d600000 - 0x80dc72fff,     6 MB (   1651 pages) NoAlloc
  0x9d3800000 - 0x9d4d20fff,    21 MB (   5409 pages) NoAlloc
  0x9db93c000 - 0x9db93efff,     0 MB (      3 pages) NoAlloc
  0x9db940000 - 0x9db943fff,     0 MB (      4 pages) NoAlloc
  0x9e0970000 - 0x9e097ffff,     0 MB (     16 pages) NoAlloc
  0x9e3a5c000 - 0x9e3d21fff,     2 MB (    710 pages) NoAlloc