[PATCH v2 2/9] tpm: Avoid code bloat when not using EFI_TCG2_PROTOCOL
Tom Rini
trini at konsulko.com
Fri Jun 21 21:19:15 CEST 2024
On Fri, Jun 21, 2024 at 11:55:42AM -0600, Simon Glass wrote:
> Hi Tom,
>
> On Fri, 21 Jun 2024 at 10:05, Tom Rini <trini at konsulko.com> wrote:
[snip]
> > Yes, I very much do not like guessing about 3 numbers instead of
> > guessing about 1 number and using the standard mechanism we already
> > have. Please use BOARD_SIZE_LIMIT as this is the standard mechanism to
> > enforce size limits on U-Boot itself.
>
> If it were that easy I would have sent a patch :-)
>
> Here is the map for this board:
>
> ImagePos Offset Size Name
> 00000000 00000000 00800000 rom
> ff800000 ff800000 00001000 intel-descriptor
> ff801000 ff801000 001ff000 intel-me
> ffef0000 ffef0000 000999f0 u-boot-with-ucode-ptr
> fff899f0 fff899f0 00005554 u-boot-dtb-with-ucode
> fff8ef50 fff8ef50 00000000 u-boot-ucode
> fff8ef50 fff8ef50 00000571 fdtmap
> fff90000 fff90000 00010000 intel-vga
> fffa0000 fffa0000 0002fc94 intel-mrc
> fffcfc94 fffcfc94 00000000 private-files
> fffff800 fffff800 00000070 x86-start16
> fffffff0 fffffff0 00000005 x86-reset16
> fffffff8 fffffff8 00000008 image-header
>
> What limit should I set on what?
Is this a trick question?
$ printf %d\\n $(( 0xfff90000 - 0xffef0000))
655360
Of course since we're less than that today, you can reduce it by
whatever other magic numbers I'm not seeing but are part of your assumed
sizes.
> - the U-Boot is the thing you are wanting to limit
> - the dtb has microcode added
> - the ucode is empty in this case
> - the fdtmap is variable in size
>
> So this all seems a bit backwards. The actual limit is that
> (u-boot-with-ucode-ptr + u-boot-dtb-with-ucode + u-boot-ucode +
> fdtmap) fits in the space available. Note that some boards don't have
> intel-vga or intel-mrc.
>
> With the other patch I sent I can have a sensible limit for all x86 boards.
And you can set the same sensible limit with the existing mechanism with
the bonus of it not making x86 different from the rest?
--
Tom
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 659 bytes
Desc: not available
URL: <https://lists.denx.de/pipermail/u-boot/attachments/20240621/b7cfd44f/attachment.sig>
More information about the U-Boot
mailing list