[PATCH 1/5] efi_loader: increase eventlog buffer size

[Masahisa Kojima]

On Wed, 7 Jul 2021 at 22:47, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
>
>
> On 7/7/21 3:36 PM, Masahisa Kojima wrote:
> > This is a preperation to add eventlog support
> > described in TCG PC Client PFP spec.
> >
> > Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> > ---
> >   lib/efi_loader/Kconfig | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
> > index b2ab48a048..a87bf3cc98 100644
> > --- a/lib/efi_loader/Kconfig
> > +++ b/lib/efi_loader/Kconfig
> > @@ -327,7 +327,7 @@ config EFI_TCG2_PROTOCOL
> >   config EFI_TCG2_PROTOCOL_EVENTLOG_SIZE
> >       int "EFI_TCG2_PROTOCOL EventLog size"
> >       depends on EFI_TCG2_PROTOCOL
> > -     default 4096
> > +     default 16384
>
> I found this text in EDK II:
>
> Minimum length(in bytes) of the system preboot TCG event log area(LAML)
> -----------------------------------------------------------------------
>
> For PC Client Implementation spec up to and including 1.2 the minimum
> log size is 64KB. (SecurityPkg/SecurityPkg.dec)

Thank you for your feedback.
I have not checked this.
TCG spec also says "The Log Area Minimum Length for the TCG event log
MUST be at least 64KB." in ACPI chapter.
I will update to set 64KB as default.

Thanks,
Masahisa Kojima

>
> Why should ours be smaller?
>
> Best regards
>
> Heinrich
>
> >       help
> >               Define the size of the EventLog for EFI_TCG2_PROTOCOL. Note that
> >               this is going to be allocated twice. One for the eventlog it self
> >