kernel.git/drivers/firmware/efi/libstub, branch linux-6.16.y

arm64: fix unnecessary rebuilding when CONFIG_DEBUG_EFI=y

2025-08-15T14:38:44Z

[ Upstream commit 344b6580472451390d070c65c27f59716a1deecb ] When CONFIG_DEBUG_EFI is enabled, some objects are needlessly rebuilt. [Steps to reproduce] Enable CONFIG_DEBUG_EFI and run 'make' twice in a clean source tree. On the second run, arch/arm64/kernel/head.o is rebuilt even though no files have changed. $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- clean $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- [ snip ] $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- CALL scripts/checksyscalls.sh AS arch/arm64/kernel/head.o AR arch/arm64/kernel/built-in.a AR arch/arm64/built-in.a AR built-in.a [ snip ] The issue is caused by the use of the $(realpath ...) function. At the time arch/arm64/kernel/Makefile is parsed on the first run, $(objtree)/vmlinux does not exist. As a result, $(realpath $(objtree)/vmlinux) expands to an empty string. On the second run of Make, $(objtree)/vmlinux already exists, so $(realpath $(objtree)/vmlinux) expands to the absolute path of vmlinux. However, this change in the command line causes arch/arm64/kernel/head.o to be rebuilt. To address this issue, use $(abspath ...) instead, which does not require the file to exist. While $(abspath ...) does not resolve symlinks, this should be fine from a debugging perspective. The GNU Make manual [1] clearly explains the difference between the two: $(realpath names...) For each file name in names return the canonical absolute name. A canonical name does not contain any . or .. components, nor any repeated path separators (/) or symlinks. In case of a failure the empty string is returned. Consult the realpath(3) documentation for a list of possible failure causes. $(abspath namees...) For each file name in names return an absolute name that does not contain any . or .. components, nor any repeated path separators (/). Note that, in contrast to realpath function, abspath does not resolve symlinks and does not require the file names to refer to an existing file or directory. Use the wildcard function to test for existence. The same problem exists in drivers/firmware/efi/libstub/Makefile.zboot. On the first run of Make, $(obj)/vmlinuz.efi.elf does not exist when the Makefile is parsed, so -DZBOOT_EFI_PATH is set to an empty string. Replace $(realpath ...) with $(abspath ...) there as well. [1]: https://www.gnu.org/software/make/manual/make.html#File-Name-Functions Fixes: 757b435aaabe ("efi: arm64: Add vmlinux debug link to the Image binary") Fixes: a050910972bb ("efi/libstub: implement generic EFI zboot") Signed-off-by: Masahiro Yamada Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250625125555.2504734-1-masahiroy@kernel.org Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

efi: Fix .data section size calculations when .sbat is present

2025-06-20T11:36:14Z

Commit 0f9a1739dd0e ("efi: zboot specific mechanism for embedding SBAT section") neglected to adjust the sizes of the .data section when CONFIG_EFI_SBAT_FILE is set. As the result, the produced PE binary is incorrect and some tools complain about it. E.g. 'sbsign' reports: # sbsign --key my.key --cert my.crt arch/arm64/boot/vmlinuz.efi warning: file-aligned section .data extends beyond end of file warning: checksum areas are greater than image size. Invalid section table? Note, '__data_size' is also used in the PE optional header and it is not entirely clear whether .sbat needs to be accounted as part of SizeOfInitializedData or not. As the header seems to be unused by the real world firmware, keeping the field equal to __data_size. Fixes: 0f9a1739dd0e ("efi: zboot specific mechanism for embedding SBAT section") Reported-by: Heinrich Schuchardt Signed-off-by: Vitaly Kuznetsov Signed-off-by: Ard Biesheuvel

efi: Drop preprocessor directives from zboot.lds

2025-06-10T16:47:55Z

Older versions of `ld` don't seem to support preprocessor directives in linker scripts, e.g. on RHEL9's ld-2.35.2-63.el9 the build fails with: ld:./drivers/firmware/efi/libstub/zboot.lds:32: ignoring invalid character `#' in expression ld:./drivers/firmware/efi/libstub/zboot.lds:33: syntax error We don't seem to need these '#ifdef', no empty .sbat section is created when CONFIG_EFI_SBAT_FILE="": # objdump -h arch/arm64/boot/vmlinuz.efi arch/arm64/boot/vmlinuz.efi: file format pei-aarch64-little Sections: Idx Name Size VMA LMA File off Algn 0 .text 00b94000 0000000000001000 0000000000001000 00001000 2**2 CONTENTS, ALLOC, LOAD, READONLY, CODE 1 .data 00000200 0000000000b95000 0000000000b95000 00b95000 2**2 CONTENTS, ALLOC, LOAD, DATA Fixes: 0f9a1739dd0e ("efi: zboot specific mechanism for embedding SBAT section") Signed-off-by: Vitaly Kuznetsov Signed-off-by: Ard Biesheuvel

Merge tag 'kbuild-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2025-06-07T17:05:35Z

Pull Kbuild updates from Masahiro Yamada: - Add support for the EXPORT_SYMBOL_GPL_FOR_MODULES() macro, which exports a symbol only to specified modules - Improve ABI handling in gendwarfksyms - Forcibly link lib-y objects to vmlinux even if CONFIG_MODULES=n - Add checkers for redundant or missing inclusion - Deprecate the extra-y syntax - Fix a genksyms bug when including enum constants from *.symref files * tag 'kbuild-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (28 commits) genksyms: Fix enum consts from a reference affecting new values arch: use always-$(KBUILD_BUILTIN) for vmlinux.lds kbuild: set y instead of 1 to KBUILD_{BUILTIN,MODULES} efi/libstub: use 'targets' instead of extra-y in Makefile module: make __mod_device_table__* symbols static scripts/misc-check: check unnecessary #include when W=1 scripts/misc-check: check missing #include when W=1 scripts/misc-check: add double-quotes to satisfy shellcheck kbuild: move W=1 check for scripts/misc-check to top-level Makefile scripts/tags.sh: allow to use alternative ctags implementation kconfig: introduce menu type enum docs: symbol-namespaces: fix reST warning with literal block kbuild: link lib-y objects to vmlinux forcibly even when CONFIG_MODULES=n tinyconfig: enable CONFIG_LD_DEAD_CODE_DATA_ELIMINATION docs/core-api/symbol-namespaces: drop table of contents and section numbering modpost: check forbidden MODULE_IMPORT_NS("module:") at compile time kbuild: move kbuild syntax processing to scripts/Makefile.build Makefile: remove dependency on archscripts for header installation Documentation/kbuild: Add new gendwarfksyms kABI rules Documentation/kbuild: Drop section numbers ...

Merge tag 'loongarch-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

2025-06-07T16:56:18Z

Pull LoongArch updates from Huacai Chen: - Adjust the 'make install' operation - Support SCHED_MC (Multi-core scheduler) - Enable ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS - Enable HAVE_ARCH_STACKLEAK - Increase max supported CPUs up to 2048 - Introduce the numa_memblks conversion - Add PWM controller nodes in dts - Some bug fixes and other small changes * tag 'loongarch-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: platform/loongarch: laptop: Unregister generic_sub_drivers on exit platform/loongarch: laptop: Add backlight power control support platform/loongarch: laptop: Get brightness setting from EC on probe LoongArch: dts: Add PWM support to Loongson-2K2000 LoongArch: dts: Add PWM support to Loongson-2K1000 LoongArch: dts: Add PWM support to Loongson-2K0500 LoongArch: vDSO: Correctly use asm parameters in syscall wrappers LoongArch: Fix panic caused by NULL-PMD in huge_pte_offset() LoongArch: Preserve firmware configuration when desired LoongArch: Avoid using $r0/$r1 as "mask" for csrxchg LoongArch: Introduce the numa_memblks conversion LoongArch: Increase max supported CPUs up to 2048 LoongArch: Enable HAVE_ARCH_STACKLEAK LoongArch: Enable ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS LoongArch: Add SCHED_MC (Multi-core scheduler) support LoongArch: Add some annotations in archhelp LoongArch: Using generic scripts/install.sh in `make install` LoongArch: Add a default install.sh

efi/libstub: use 'targets' instead of extra-y in Makefile

2025-06-05T20:42:49Z

These objects are built as prerequisites of %.stub.o files. There is no need to use extra-y, which is planned for deprecation. Acked-by: Ard Biesheuvel Signed-off-by: Masahiro Yamada

Merge tag 'efi-next-for-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

2025-05-30T19:42:57Z

Pull EFI updates from Ard Biesheuvel: "Not a lot going on in the EFI tree this cycle. The only thing that stands out is the new support for SBAT metadata, which was a bit contentious when it was first proposed, because in the initial incarnation, it would have required us to maintain a revocation index, and bump it each time a vulnerability affecting UEFI secure boot got fixed. This was shot down for obvious reasons. This time, only the changes needed to emit the SBAT section into the PE/COFF image are being carried upstream, and it is up to the distros to decide what to put in there when creating and signing the build. This only has the EFI zboot bits (which the distros will be using for arm64); the x86 bzImage changes should be arriving next cycle, presumably via the -tip tree. Summary: - Add support for emitting a .sbat section into the EFI zboot image, so that downstreams can easily include revocation metadata in the signed EFI images - Align PE symbolic constant names with other projects - Bug fix for the efi_test module - Log the physical address and size of the EFI memory map when failing to map it - A kerneldoc fix for the EFI stub code" * tag 'efi-next-for-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: include: pe.h: Fix PE definitions efi/efi_test: Fix missing pending status update in getwakeuptime efi: zboot specific mechanism for embedding SBAT section efi/libstub: Describe missing 'out' parameter in efi_load_initrd efi: Improve logging around memmap init

LoongArch: Enable HAVE_ARCH_STACKLEAK

2025-05-30T13:45:42Z

Add support for the stackleak feature. It initializes the stack with the poison value before returning from system calls which improves the kernel security. At the same time, disables the plugin in EFI stub code because EFI stub is out of scope for the protection. Tested on Loongson-3A5000 (enable GCC_PLUGIN_STACKLEAK and LKDTM): # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT # dmesg lkdtm: Performing direct entry STACKLEAK_ERASING lkdtm: stackleak stack usage: high offset: 320 bytes current: 448 bytes lowest: 1264 bytes tracked: 1264 bytes untracked: 208 bytes poisoned: 14528 bytes low offset: 64 bytes lkdtm: OK: the rest of the thread stack is properly erased Signed-off-by: Youling Tang Signed-off-by: Huacai Chen

include: pe.h: Fix PE definitions

2025-05-21T14:46:37Z

* Rename constants to their standard PE names: - MZ_MAGIC -> IMAGE_DOS_SIGNATURE - PE_MAGIC -> IMAGE_NT_SIGNATURE - PE_OPT_MAGIC_PE32_ROM -> IMAGE_ROM_OPTIONAL_HDR_MAGIC - PE_OPT_MAGIC_PE32 -> IMAGE_NT_OPTIONAL_HDR32_MAGIC - PE_OPT_MAGIC_PE32PLUS -> IMAGE_NT_OPTIONAL_HDR64_MAGIC - IMAGE_DLL_CHARACTERISTICS_NX_COMPAT -> IMAGE_DLLCHARACTERISTICS_NX_COMPAT * Import constants and their description from readpe and file projects which contains current up-to-date information: - IMAGE_FILE_MACHINE_* - IMAGE_FILE_* - IMAGE_SUBSYSTEM_* - IMAGE_DLLCHARACTERISTICS_* - IMAGE_DLLCHARACTERISTICS_EX_* - IMAGE_DEBUG_TYPE_* * Add missing IMAGE_SCN_* constants and update their incorrect description * Fix incorrect value of IMAGE_SCN_MEM_PURGEABLE constant * Add description for win32_version and loader_flags PE fields Signed-off-by: Pali Rohár Signed-off-by: Ard Biesheuvel

Merge branch 'efi-sbat' into efi/next

2025-05-21T13:32:06Z