On 3/5/24 10:00 AM, Ilias Apalodimas wrote: > Hi Ard, > > On Mon, 4 Mar 2024 at 12:44, Ard Biesheuvel <ardb+git@xxxxxxxxxx> wrote: >> From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> >> >> If the virtual firmware implements TPM support, TCG2 protocol will be >> used for kernel measurements and event logging support. But in CC >> environment, not all platforms support or enable the TPM feature. UEFI >> specification [1] exposes protocol and interfaces used for kernel >> measurements in CC platforms without TPM support. >> >> More details about the EFI CC measurements and logging can be found >> in [1]. >> >> Link: https://uefi.org/specs/UEFI/2.10/38_Confidential_Computing.html#efi-cc-measurement-protocol [1] >> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> >> [ardb: Drop code changes, keep typedefs and #define's only] >> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> >> --- >> drivers/firmware/efi/libstub/efistub.h | 79 ++++++++++++++++++++ >> include/linux/efi.h | 1 + >> 2 files changed, 80 insertions(+) >> > [...] > >> + >> +struct efi_cc_event { >> + u32 event_size; >> + struct { >> + u32 header_size; >> + u16 header_version; >> + u32 mr_index; >> + u32 event_type; >> + } __packed event_header; >> + u8 event_data[0]; > We should define this as a flexible array member instead of a zero-length array? > The spec is funny and defines this as event_data[1]. I think we aren't > using the sizeof(struct efi_cc_event) anywhere, so if this struct is > not used as a member of another struct or an array we can omit it > entirely. Flexible array is also fine or we can just add a comment like "u8[] event follows here" like in struct efi_tcg2_event . > > [...] > > Cheers > /Ilias -- Sathyanarayanan Kuppuswamy Linux Kernel Developer
