| Message ID | 20221129175616.2089294-1-ardb@kernel.org |
|---|---|
| Headers | show |
| Series | efi: Add generic magic number in header | expand |
On Tue, Nov 29, 2022 at 18:56:14 +0100, Ard Biesheuvel wrote: > This is a minimal respin of the RFC patch I sent out a few week ago. No > changes were applied except the /0x30/0x38 typo fix and some additional > wording in the commit log. I also added a patch to make the command line > initrd loader always built-in. > > The purpose of all of this is to create *and document* a common baseline > for EFI booting of Linux. (I know I promised some documentation myself, > but I simply don't have time for that, so if anyone feels so inclined, > please go ahead). > > The idea is that EFI images with the LINUX_PE_MAGIC number are > guaranteed to support: > - initrd loading via LoadFile2 > - initrd loading via the command line > - (on x86) mixed mode boot via the .compat entry point > - other things I missed? > > Architectures such as arm64 and RISC-V already have their own magic > numbers, in which case the PE/COFF major/minor image version should be > inspected, where 1.1 corresponds with the set described above. > > If other architectures want to create hybrid images as well, it would be > better to use a different offset to store the magic number, so that the > generic EFI one can be carried as well. The reason for deviating from > this for arm64 and RISC-V is the simple fact that existing images > already exist, so for those architectures, we have to consider both > anyway. > > Cc: Huacai Chen <chenhuacai@kernel.org> > Cc: Atish Patra <atishp@rivosinc.com> > Cc: Heinrich Schuchardt <heinrich.schuchardt@canonical.com> > Cc: Daniel Kiper <daniel.kiper@oracle.com> > Cc: Leif Lindholm <quic_llindhol@quicinc.com> For the series: Acked-by: Leif Lindholm <quic_llindhol@quicinc.com> Thanks! > > Ard Biesheuvel (2): > efi: libstub: Always enable initrd command line loader and bump > version > efi: Put Linux specific magic number in the DOS header > > arch/loongarch/kernel/head.S | 3 ++- > arch/x86/boot/header.S | 3 ++- > drivers/firmware/efi/Kconfig | 15 --------------- > drivers/firmware/efi/libstub/efi-stub-helper.c | 3 +-- > drivers/firmware/efi/libstub/zboot-header.S | 3 ++- > include/linux/pe.h | 9 ++++++++- > 6 files changed, 15 insertions(+), 21 deletions(-) > > -- > 2.35.1 >
This is a minimal respin of the RFC patch I sent out a few week ago. No changes were applied except the /0x30/0x38 typo fix and some additional wording in the commit log. I also added a patch to make the command line initrd loader always built-in. The purpose of all of this is to create *and document* a common baseline for EFI booting of Linux. (I know I promised some documentation myself, but I simply don't have time for that, so if anyone feels so inclined, please go ahead). The idea is that EFI images with the LINUX_PE_MAGIC number are guaranteed to support: - initrd loading via LoadFile2 - initrd loading via the command line - (on x86) mixed mode boot via the .compat entry point - other things I missed? Architectures such as arm64 and RISC-V already have their own magic numbers, in which case the PE/COFF major/minor image version should be inspected, where 1.1 corresponds with the set described above. If other architectures want to create hybrid images as well, it would be better to use a different offset to store the magic number, so that the generic EFI one can be carried as well. The reason for deviating from this for arm64 and RISC-V is the simple fact that existing images already exist, so for those architectures, we have to consider both anyway. Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Atish Patra <atishp@rivosinc.com> Cc: Heinrich Schuchardt <heinrich.schuchardt@canonical.com> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: Leif Lindholm <quic_llindhol@quicinc.com> Ard Biesheuvel (2): efi: libstub: Always enable initrd command line loader and bump version efi: Put Linux specific magic number in the DOS header arch/loongarch/kernel/head.S | 3 ++- arch/x86/boot/header.S | 3 ++- drivers/firmware/efi/Kconfig | 15 --------------- drivers/firmware/efi/libstub/efi-stub-helper.c | 3 +-- drivers/firmware/efi/libstub/zboot-header.S | 3 ++- include/linux/pe.h | 9 ++++++++- 6 files changed, 15 insertions(+), 21 deletions(-)