Hello Linus, A bit more going on than usual in the EFI subsystem. The main driver for this has been the introduction of the LoonArch architecture last cycle, which inspired some cleanup and refactoring of the EFI code. Another driver for EFI changes this cycle and in the future is confidential compute. The LoongArch architecture does not use either struct bootparams or DT natively [yet], and so passing information between the EFI stub and the core kernel using either of those is undesirable. And in general, overloading DT has been a source of issues on arm64, so using DT for this on new architectures is a to avoid for the time being (even if we might converge on something DT based for non-x86 architectures in the future). For this reason, in addition to the patch that enables EFI boot for LoongArch, there are a number of refactoring patches applied on top of which separate the DT bits from the generic EFI stub bits. These changes are on a separate topich branch that has been shared with the LoongArch maintainers, who will include it in their pull request as well. This is not ideal, but the best way to manage the conflicts without stalling LoongArch for another cycle. Another development inspired by LoongArch is the newly added support for EFI based decompressors. Instead of adding yet another arch-specific incarnation of this pattern for LoongArch, we are introducing a EFI app based on the existing EFI libstub infrastructure that encapulates the decompression code we use on other architectures, but in a way that is fully generic. This has been developed and tested in collaboration with distro and systemd folks, who are eager to start using this for systemd-boot and also for arm64 secure boot on Fedora. Note that the EFI zimage files this introduces can also be decompressed by non-EFI bootloaders if needed, as the image header describes the location of the payload inside the image, and the type of compression that was used. (Note that Fedora's arm64 GRUB is buggy [0] so you'll need a recent version or switch to systemd-boot in order to use this.) Finally, we are adding TPM measurement of the kernel command line provided by EFI. There is an oversight in the TCG spec which results in a blind spot for command line arguments passed to loaded images, which means that either the loader or the stub needs to take the measurement. Given the combinatorial explosion I am anticipating when it comes to firmware/bootloader stacks and firmware based attestation protocols (SEV-SNP, TDX, DICE, DRTM), it is good to set a baseline now when it comes to EFI measured boot, which is that the kernel measures the initrd and command line. Intermediate loaders can measure additional assets if needed, but with the baseline in place, we can deploy measured boot in a meaningful way even if you boot into Linux straight from the EFI firmware. Please pull the changes below. -- Ard. The following changes since commit 568035b01cfb107af8d2e4bd2fb9aea22cf5b868: Linux 6.0-rc1 (2022-08-14 15:50:18 -0700) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git tags/efi-next-for-v6.1 for you to fetch changes up to d3549a938b73f203ef522562ae9f2d38aa43d234: efi/arm64: libstub: avoid SetVirtualAddressMap() when possible (2022-09-27 13:26:16 +0200) Cc: Huacai Chen <chenhuacai@xxxxxxxxxxx> Cc: Ilias Apalodimas <ilias.apalodimas@xxxxxxxxxx> [0] https://github.com/rhboot/grub2/commit/7710c05ea38995f558a84a27ae0cb89968383420 ---------------------------------------------------------------- EFI updates for v6.1 - implement EFI boot support for LoongArch - implement generic EFI compressed boot support for arm64, RISC-V and LoongArch, none of which implement a decompressor today - measure the kernel command line into the TPM if measured boot is in effect - refactor the EFI stub code in order to isolate DT dependencies for architectures other than x86 - avoid calling SetVirtualAddressMap() on arm64 if the configured size of the VA space guarantees that doing so is unnecessary - move some ARM specific code out of the generic EFI source files - unmap kernel code from the x86 mixed mode 1:1 page tables ---------------------------------------------------------------- Ard Biesheuvel (23): efi/x86-mixed: move unmitigated RET into .rodata Merge tag 'efi-loongarch-for-v6.1' into efi/next efi/libstub: add some missing EFI prototypes efi/libstub: use EFI provided memcpy/memset routines efi/libstub: move efi_system_table global var into separate object efi/libstub: implement generic EFI zboot riscv: efi: enable generic EFI compressed boot loongarch: efi: enable generic EFI compressed boot arm64: efi: enable generic EFI compressed boot efi: libstub: fix type confusion for load_options_size efi: libstub: drop pointless get_memory_map() call efi: libstub: avoid efi_get_memory_map() for allocating the virt map efi: libstub: simplify efi_get_memory_map() and struct efi_boot_memmap efi: libstub: remove pointless goto kludge efi: libstub: unify initrd loading between architectures efi: libstub: remove DT dependency from generic stub efi: libstub: install boot-time memory map as config table efi/loongarch: libstub: remove dependency on flattened DT Merge tag 'efi-loongarch-for-v6.1-2' into HEAD efi/arm: libstub: move ARM specific code out of generic routines efi: libstub: fix up the last remaining open coded boot service call efi: zboot: create MemoryMapped() device path for the parent if needed efi/arm64: libstub: avoid SetVirtualAddressMap() when possible Huacai Chen (1): efi/loongarch: Add efistub booting support Ilias Apalodimas (2): efi/libstub: refactor the initrd measuring functions efi/libstub: measure EFI LoadOptions Documentation/arm/uefi.rst | 4 - arch/arm/include/asm/efi.h | 3 +- arch/arm/kernel/efi.c | 79 +++++++ arch/arm/kernel/setup.c | 2 +- arch/arm64/Makefile | 9 +- arch/arm64/boot/.gitignore | 1 + arch/arm64/boot/Makefile | 6 + arch/arm64/kernel/image-vars.h | 13 -- arch/loongarch/Kconfig | 12 +- arch/loongarch/Makefile | 18 +- arch/loongarch/boot/.gitignore | 1 + arch/loongarch/boot/Makefile | 14 +- arch/loongarch/include/asm/bootinfo.h | 2 +- arch/loongarch/include/asm/efi.h | 11 +- arch/loongarch/kernel/efi-header.S | 99 ++++++++ arch/loongarch/kernel/efi.c | 33 ++- arch/loongarch/kernel/env.c | 13 +- arch/loongarch/kernel/head.S | 22 ++ arch/loongarch/kernel/image-vars.h | 27 +++ arch/loongarch/kernel/setup.c | 15 +- arch/loongarch/kernel/vmlinux.lds.S | 1 + arch/riscv/Makefile | 6 +- arch/riscv/boot/.gitignore | 1 + arch/riscv/boot/Makefile | 6 + arch/riscv/kernel/image-vars.h | 9 - arch/x86/platform/efi/efi_64.c | 18 +- arch/x86/platform/efi/efi_thunk_64.S | 13 +- drivers/firmware/efi/Kconfig | 45 +++- drivers/firmware/efi/efi-init.c | 61 +---- drivers/firmware/efi/efi.c | 15 ++ drivers/firmware/efi/libstub/Makefile | 32 ++- drivers/firmware/efi/libstub/Makefile.zboot | 70 ++++++ drivers/firmware/efi/libstub/arm64-stub.c | 27 ++- drivers/firmware/efi/libstub/efi-stub-helper.c | 290 ++++++++++++++---------- drivers/firmware/efi/libstub/efi-stub.c | 118 ++++------ drivers/firmware/efi/libstub/efistub.h | 69 +++--- drivers/firmware/efi/libstub/fdt.c | 175 +++++++------- drivers/firmware/efi/libstub/file.c | 23 +- drivers/firmware/efi/libstub/intrinsics.c | 30 +++ drivers/firmware/efi/libstub/loongarch-stub.c | 102 +++++++++ drivers/firmware/efi/libstub/mem.c | 93 ++++---- drivers/firmware/efi/libstub/randomalloc.c | 25 +- drivers/firmware/efi/libstub/relocate.c | 21 +- drivers/firmware/efi/libstub/systable.c | 8 + drivers/firmware/efi/libstub/x86-stub.c | 33 +-- drivers/firmware/efi/libstub/zboot-header.S | 143 ++++++++++++ drivers/firmware/efi/libstub/zboot.c | 302 +++++++++++++++++++++++++ drivers/firmware/efi/libstub/zboot.lds | 44 ++++ include/linux/efi.h | 35 +++ include/linux/pe.h | 2 + 50 files changed, 1638 insertions(+), 563 deletions(-) create mode 100644 arch/loongarch/kernel/efi-header.S create mode 100644 arch/loongarch/kernel/image-vars.h create mode 100644 drivers/firmware/efi/libstub/Makefile.zboot create mode 100644 drivers/firmware/efi/libstub/intrinsics.c create mode 100644 drivers/firmware/efi/libstub/loongarch-stub.c create mode 100644 drivers/firmware/efi/libstub/systable.c create mode 100644 drivers/firmware/efi/libstub/zboot-header.S create mode 100644 drivers/firmware/efi/libstub/zboot.c create mode 100644 drivers/firmware/efi/libstub/zboot.lds
