Re: [PATCH 3/6] libstub,tpm: provide indication of failure when getting event log

[Ilias Apalodimas]

Hi Gregory,

On Fri, 6 Sept 2024 at 23:28, Gregory Price <gourry@xxxxxxxxxx> wrote:
>
> If get_event_log fails, at least provide an indicator of this failure
> to assist debugging later failures that attempt to interact with it.
>
> Signed-off-by: Gregory Price <gourry@xxxxxxxxxx>
> ---
>  drivers/firmware/efi/libstub/tpm.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c
> index df3182f2e63a..192914e04e0f 100644
> --- a/drivers/firmware/efi/libstub/tpm.c
> +++ b/drivers/firmware/efi/libstub/tpm.c
> @@ -185,8 +185,10 @@ void efi_retrieve_eventlog(void)
>                         get_efi_config_table(EFI_CC_FINAL_EVENTS_TABLE_GUID);
>         }
>
> -       if (status != EFI_SUCCESS || !log_location)
> +       if (status != EFI_SUCCESS || !log_location) {
> +               efi_err("TPM unable to provide Event Log\n");

s/provide/retrieve/ and yes the print is going to be useful.  Do you
know if the EventLog is mandatory. Reading at the spec GetEventlog
only has 2 return values, which implies you can't return "Not
supported", but it's not explicitly stated anywhere

Thanks
/Ilias
>                 return;
> +       }
>
>         efi_retrieve_tcg2_eventlog(version, log_location, log_last_entry,
>                                    truncated, final_events_table);
> --
> 2.43.0
>