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6 daysMerge tag 'efi-next-for-v6.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: "The usual trickle of EFI contributions: - Parse SMBIOS tables in memory directly on Macbooks that do not implement the EFI SMBIOS protocol - Obtain EDID information from the primary display while running in the EFI stub, and expose it via bootparams on x86 (generic method is in the works, and will likely land during the next cycle) - Bring CPER handling for ARM systems up to data with the latest EFI spec changes - Various cosmetic changes" * tag 'efi-next-for-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: docs: efi: add CPER functions to driver-api efi/cper: align ARM CPER type with UEFI 2.9A/2.10 specs efi/cper: Add a new helper function to print bitmasks efi/cper: Adjust infopfx size to accept an extra space RAS: Report all ARM processor CPER information to userspace efi/libstub: x86: Store EDID in boot_params efi/libstub: gop: Add support for reading EDID efi/libstub: gop: Initialize screen_info in helper function efi/libstub: gop: Find GOP handle instead of GOP data efi: Fix trailing whitespace in header file efi/memattr: Convert efi_memattr_init() return type to void efi: stmm: fix kernel-doc "bad line" warnings efi/riscv: Remove the useless failure return message print efistub/x86: Add fallback for SMBIOS record lookup
8 daysMerge tag 'x86_mm_for_v6.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Borislav Petkov: - Use the proper accessors when reading CR3 as part of the page level transitions (5-level to 4-level, the use case being kexec) so that only the physical address in CR3 is picked up and not flags which are above the physical mask shift - Clean up and unify __phys_addr_symbol() definitions * tag 'x86_mm_for_v6.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi/libstub: Fix page table access in 5-level to 4-level paging transition x86/boot: Fix page table access in 5-level to 4-level paging transition x86/mm: Unify __phys_addr_symbol()
2025-11-18efi/libstub: x86: Store EDID in boot_paramsThomas Zimmermann
Retrieve the GOP device's EDID information in the kernel's boot parameters. Makes the data avaialble to kernel graphics code and drives, such as efidrm. With efidrm, the EDID is now also available to user-space compositors via standard DRM interfaces. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-11-18efi/libstub: gop: Add support for reading EDIDThomas Zimmermann
Add support for EFI_EDID_DISCOVERED_PROTOCOL and EFI_EDID_ACTIVE_PROTOCOL as defined in UEFI 2.8, sec 12.9. Define GUIDs and data structures in the rsp header files. In the GOP setup function, read the EDID of the primary GOP device. First try EFI_EDID_ACTIVE_PROTOCOL, which supports user-specified EDID data. Or else try EFI_EDID_DISCOVERED_PROTOCOL, which returns the display device's native EDID. If no EDID could be retrieved, clear the storage. Rename efi_setup_gop() to efi_setup_graphics() to reflect the changes Let callers pass an optional instance of struct edid_data, if they are interested. While screen_info and edid_info come from the same device handle, they should be considered indendent data. The former refers to the graphics mode, the latter refers to the display device. GOP devices might not provide both. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-11-18efi/libstub: gop: Initialize screen_info in helper functionThomas Zimmermann
Move initialization of screen_info into a single helper function. Frees up space in the main setup helper for adding EDID support. No functional changes. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-11-18efi/libstub: gop: Find GOP handle instead of GOP dataThomas Zimmermann
The device handle of the GOP device is required to retrieve the correct EDID data. Find the handle instead of the GOP data. Still return the GOP data in the function arguments, as we already looked it up. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-11-06efistub/x86: Add fallback for SMBIOS record lookupFrancesco Pompo
Some Apple EFI firmwares do not provide the SMBIOS Protocol, causing efi_get_smbios_record() to fail. This prevents retrieval of system information such as product name, which is needed by apple_set_os() to enable the integrated GPU on dual-graphics Intel MacBooks. Add a fallback that directly parses the SMBIOS entry point table when the protocol is unavailable. Signed-off-by: Francesco Pompo <francescopompo2@gmail.com> [ardb: cosmetic tweaks] Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-11-05efi/libstub: Fix page table access in 5-level to 4-level paging transitionUsama Arif
When transitioning from 5-level to 4-level paging, the existing code incorrectly accesses page table entries by directly dereferencing CR3 and applying PAGE_MASK. This approach has several issues: - __native_read_cr3() returns the raw CR3 register value, which on x86_64 includes not just the physical address but also flags Bits above the physical address width of the system (i.e. above __PHYSICAL_MASK_SHIFT) are also not masked. - The pgd value is masked by PAGE_SIZE which doesn't take into account the higher bits such as _PAGE_BIT_NOPTISHADOW. Replace this with proper accessor functions: - native_read_cr3_pa(): Uses CR3_ADDR_MASK to additionally mask metadata out of CR3 (like SME or LAM bits). All remaining bits are real address bits or reserved and must be 0. - mask pgd value with PTE_PFN_MASK instead of PAGE_MASK, accounting for flags above bit 51 (_PAGE_BIT_NOPTISHADOW in particular). Bits below 51, but above the max physical address are reserved and must be 0. Fixes: cb1c9e02b0c1 ("x86/efistub: Perform 4/5 level paging switch from the stub") Reported-by: Michael van der Westhuizen <rmikey@meta.com> Reported-by: Tobias Fleig <tfleig@meta.com> Co-developed-by: Kiryl Shutsemau <kas@kernel.org> Signed-off-by: Kiryl Shutsemau <kas@kernel.org> Signed-off-by: Usama Arif <usamaarif642@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://patch.msgid.link/20251103141002.2280812-3-usamaarif642@gmail.com
2025-10-30kbuild: Add '-fms-extensions' to areas with dedicated CFLAGSNathan Chancellor
This is a follow up to commit c4781dc3d1cf ("Kbuild: enable -fms-extensions") but in a separate change due to being substantially different from the initial submission. There are many places within the kernel that use their own CFLAGS instead of the main KBUILD_CFLAGS, meaning code written with the main kernel's use of '-fms-extensions' in mind that may be tangentially included in these areas will result in "error: declaration does not declare anything" messages from the compiler. Add '-fms-extensions' to all these areas to ensure consistency, along with -Wno-microsoft-anon-tag to silence clang's warning about use of the extension that the kernel cares about using. parisc does not build with clang so it does not need this warning flag. LoongArch does not need it either because -W flags from KBUILD_FLAGS are pulled into cflags-vdso. Reported-by: Christian Brauner <brauner@kernel.org> Closes: https://lore.kernel.org/20251030-meerjungfrau-getrocknet-7b46eacc215d@brauner/ Reviewed-by: Christian Brauner <brauner@kernel.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2025-10-05Merge tag 'efi-next-for-v6.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: - Document what OVMF stands for (Open Virtual Machine Firmware) - Clear NX restrictions also from 'more reliable' type memory when using the DXE service API * tag 'efi-next-for-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi/x86: Memory protection on EfiGcdMemoryTypeMoreReliable efi: Explain OVMF acronym in OVMF_DEBUG_LOG help text
2025-09-29efi/x86: Memory protection on EfiGcdMemoryTypeMoreReliableLenny Szubowicz
Check for needed memory protection changes on EFI DXE GCD memory space descriptors with type EfiGcdMemoryTypeMoreReliable in addition to EfiGcdMemoryTypeSystemMemory. This fixes a fault on entry into the decompressed kernel from the EFI stub that occurs when the memory allocated for the decompressed kernel is more reliable memory, has NX/XP set, and the kernel needs to use the EFI DXE protocol to adjust memory protections. The memory descriptors returned by the DXE protocol GetMemorySpaceDescriptor() service use a different GCD memory type to distinguish more reliable memory ranges from their conventional counterparts. This is in contrast to the EFI memory descriptors returned by the EFI GetMemoryMap() service which use the EFI_MEMORY_MORE_RELIABLE memory attributes flag to identify EFI_CONVENTIONAL_MEMORY type regions that have this additional property. Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-09-03efistub/x86: Remap inittext read-execute when neededArd Biesheuvel
Recent EFI x86 systems are more strict when it comes to mapping boot images, and require that mappings are either read-write or read-execute. Now that the boot code is being cleaned up and refactored, most of it is being moved into .init.text [where it arguably belongs] but that implies that when booting on such strict EFI firmware, we need to take care to map .init.text (and the .altinstr_aux section that follows it) read-execute as well. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250828102202.1849035-44-ardb+git@google.com
2025-08-09Merge tag 'efi-next-for-v6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: - Expose the OVMF firmware debug log via sysfs - Lower the default log level for the EFI stub to avoid corrupting any splash screens with unimportant diagnostic output * tag 'efi-next-for-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi: add API doc entry for ovmf_debug_log efistub: Lower default log level efi: add ovmf debug log driver
2025-07-29Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "A quick summary: perf support for Branch Record Buffer Extensions (BRBE), typical PMU hardware updates, small additions to MTE for store-only tag checking and exposing non-address bits to signal handlers, HAVE_LIVEPATCH enabled on arm64, VMAP_STACK forced on. There is also a TLBI optimisation on hardware that does not require break-before-make when changing the user PTEs between contiguous and non-contiguous. More details: Perf and PMU updates: - Add support for new (v3) Hisilicon SLLC and DDRC PMUs - Add support for Arm-NI PMU integrations that share interrupts between clock domains within a given instance - Allow SPE to be configured with a lower sample period than the minimum recommendation advertised by PMSIDR_EL1.Interval - Add suppport for Arm's "Branch Record Buffer Extension" (BRBE) - Adjust the perf watchdog period according to cpu frequency changes - Minor driver fixes and cleanups Hardware features: - Support for MTE store-only checking (FEAT_MTE_STORE_ONLY) - Support for reporting the non-address bits during a synchronous MTE tag check fault (FEAT_MTE_TAGGED_FAR) - Optimise the TLBI when folding/unfolding contiguous PTEs on hardware with FEAT_BBM (break-before-make) level 2 and no TLB conflict aborts Software features: - Enable HAVE_LIVEPATCH after implementing arch_stack_walk_reliable() and using the text-poke API for late module relocations - Force VMAP_STACK always on and change arm64_efi_rt_init() to use arch_alloc_vmap_stack() in order to avoid KASAN false positives ACPI: - Improve SPCR handling and messaging on systems lacking an SPCR table Debug: - Simplify the debug exception entry path - Drop redundant DBG_MDSCR_* macros Kselftests: - Cleanups and improvements for SME, SVE and FPSIMD tests Miscellaneous: - Optimise loop to reduce redundant operations in contpte_ptep_get() - Remove ISB when resetting POR_EL0 during signal handling - Mark the kernel as tainted on SEA and SError panic - Remove redundant gcs_free() call" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits) arm64/gcs: task_gcs_el0_enable() should use passed task arm64: Kconfig: Keep selects somewhat alphabetically ordered arm64: signal: Remove ISB when resetting POR_EL0 kselftest/arm64: Handle attempts to disable SM on SME only systems kselftest/arm64: Fix SVE write data generation for SME only systems kselftest/arm64: Test SME on SME only systems in fp-ptrace kselftest/arm64: Test FPSIMD format data writes via NT_ARM_SVE in fp-ptrace kselftest/arm64: Allow sve-ptrace to run on SME only systems arm64/mm: Drop redundant addr increment in set_huge_pte_at() kselftest/arm4: Provide local defines for AT_HWCAP3 arm64: Mark kernel as tainted on SAE and SError panic arm64/gcs: Don't call gcs_free() when releasing task_struct drivers/perf: hisi: Support PMUs with no interrupt drivers/perf: hisi: Relax the event number check of v2 PMUs drivers/perf: hisi: Add support for HiSilicon SLLC v3 PMU driver drivers/perf: hisi: Use ACPI driver_data to retrieve SLLC PMU information drivers/perf: hisi: Add support for HiSilicon DDRC v3 PMU driver drivers/perf: hisi: Simplify the probe process for each DDRC version perf/arm-ni: Support sharing IRQs within an NI instance perf/arm-ni: Consolidate CPU affinity handling ...
2025-07-28Merge tag 'hardening-v6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - Introduce and start using TRAILING_OVERLAP() helper for fixing embedded flex array instances (Gustavo A. R. Silva) - mux: Convert mux_control_ops to a flex array member in mux_chip (Thorsten Blum) - string: Group str_has_prefix() and strstarts() (Andy Shevchenko) - Remove KCOV instrumentation from __init and __head (Ritesh Harjani, Kees Cook) - Refactor and rename stackleak feature to support Clang - Add KUnit test for seq_buf API - Fix KUnit fortify test under LTO * tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits) sched/task_stack: Add missing const qualifier to end_of_stack() kstack_erase: Support Clang stack depth tracking kstack_erase: Add -mgeneral-regs-only to silence Clang warnings init.h: Disable sanitizer coverage for __init and __head kstack_erase: Disable kstack_erase for all of arm compressed boot code x86: Handle KCOV __init vs inline mismatches arm64: Handle KCOV __init vs inline mismatches s390: Handle KCOV __init vs inline mismatches arm: Handle KCOV __init vs inline mismatches mips: Handle KCOV __init vs inline mismatch powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON configs/hardening: Enable CONFIG_KSTACK_ERASE stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth stackleak: Rename STACKLEAK to KSTACK_ERASE seq_buf: Introduce KUnit tests string: Group str_has_prefix() and strstarts() kunit/fortify: Add back "volatile" for sizeof() constants acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings ...
2025-07-21stackleak: Rename STACKLEAK to KSTACK_ERASEKees Cook
In preparation for adding Clang sanitizer coverage stack depth tracking that can support stack depth callbacks: - Add the new top-level CONFIG_KSTACK_ERASE option which will be implemented either with the stackleak GCC plugin, or with the Clang stack depth callback support. - Rename CONFIG_GCC_PLUGIN_STACKLEAK as needed to CONFIG_KSTACK_ERASE, but keep it for anything specific to the GCC plugin itself. - Rename all exposed "STACKLEAK" names and files to "KSTACK_ERASE" (named for what it does rather than what it protects against), but leave as many of the internals alone as possible to avoid even more churn. While here, also split "prev_lowest_stack" into CONFIG_KSTACK_ERASE_METRICS, since that's the only place it is referenced from. Suggested-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250717232519.2984886-1-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>
2025-07-15efistub: Lower default log levelAaron Kling
Some uefi implementations will write the efistub logs to the display over a splash image. This is not desirable for debug and info logs, so lower the default efi log level to exclude them. Suggested-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Aaron Kling <webgeek1234@gmail.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-07-08arm64: fix unnecessary rebuilding when CONFIG_DEBUG_EFI=yMasahiro Yamada
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 <masahiroy@kernel.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250625125555.2504734-1-masahiroy@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2025-06-20efi: Fix .data section size calculations when .sbat is presentVitaly Kuznetsov
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 <heinrich.schuchardt@gmx.de> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-06-10efi: Drop preprocessor directives from zboot.ldsVitaly Kuznetsov
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 <vkuznets@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-06-07Merge tag 'kbuild-v6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild 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 <linux/export.h> 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 <linux/export.h> when W=1 scripts/misc-check: check missing #include <linux/export.h> 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 ...
2025-06-07Merge tag 'loongarch-6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson 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
2025-06-06efi/libstub: use 'targets' instead of extra-y in MakefileMasahiro Yamada
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 <ardb@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-05-30Merge tag 'efi-next-for-v6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi 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
2025-05-30LoongArch: Enable HAVE_ARCH_STACKLEAKYouling Tang
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 <tangyouling@kylinos.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2025-05-21include: pe.h: Fix PE definitionsPali Rohár
* 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 <pali@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-05-21Merge branch 'efi-sbat' into efi/nextArd Biesheuvel
2025-05-21efi: zboot specific mechanism for embedding SBAT sectionVitaly Kuznetsov
SBAT is a mechanism which improves SecureBoot revocations of UEFI binaries by introducing a generation-based technique. Compromised or vulnerable UEFI binaries can be prevented from booting by bumping the minimal required generation for the specific component in the bootloader. More information on the SBAT can be obtained here: https://github.com/rhboot/shim/blob/main/SBAT.md Upstream Linux kernel does not currently participate in any way in SBAT as there's no existing policy in how SBAT generation number should be defined. Keep the status quo and provide a mechanism for distro vendors and anyone else who signs their kernel for SecureBoot to include their own SBAT data. This leaves the decision on the policy to the vendor. Basically, each distro implementing SecureBoot today, will have an option to inject their own SBAT data during kernel build and before it gets signed by their SecureBoot CA. Different distro do not need to agree on the common SBAT component names or generation numbers as each distro ships its own 'shim' with their own 'vendor_cert'/'vendor_db' Implement support for embedding SBAT data for architectures using zboot (arm64, loongarch, riscv). Put '.sbat' section in between '.data' and '.text' as the former also covers '.bss' and thus must be the last one. Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-05-17x86/mm/64: Make 5-level paging support unconditionalKirill A. Shutemov
Both Intel and AMD CPUs support 5-level paging, which is expected to become more widely adopted in the future. All major x86 Linux distributions have the feature enabled. Remove CONFIG_X86_5LEVEL and related #ifdeffery for it to make it more readable. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250516123306.3812286-4-kirill.shutemov@linux.intel.com
2025-05-09efi/libstub: Describe missing 'out' parameter in efi_load_initrdHans Zhang
The function efi_load_initrd() had a documentation warning due to the missing description for the 'out' parameter. Add the parameter description to the kernel-doc comment to resolve the warning and improve API documentation. Fixes the following compiler warning: drivers/firmware/efi/libstub/efi-stub-helper.c:611: warning: Function parameter or struct member 'out' not described in 'efi_load_initrd' Fixes: f4dc7fffa987 ("efi: libstub: unify initrd loading between architectures") Signed-off-by: Hans Zhang <18255117159@163.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-04-06x86/boot: Move the EFI mixed mode startup code back under arch/x86, into ↵Ard Biesheuvel
startup/ Linus expressed a strong preference for arch-specific asm code (i.e., virtually all of it) to reside under arch/ rather than anywhere else. So move the EFI mixed mode startup code back, and put it under arch/x86/boot/startup/ where all shared x86 startup code is going to live. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20250401133416.1436741-11-ardb+git@google.com
2025-03-29Merge tag 'efi-next-for-v6.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: - Decouple mixed mode startup code from the traditional x86 decompressor - Revert zero-length file hack in efivarfs - Prevent EFI zboot from using the CopyMem/SetMem boot services after ExitBootServices() - Update EFI zboot to use the ZLIB/ZSTD library interfaces directly * tag 'efi-next-for-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi/libstub: Avoid legacy decompressor zlib/zstd wrappers efi/libstub: Avoid CopyMem/SetMem EFI services after ExitBootServices efi: efibc: change kmalloc(size * count, ...) to kmalloc_array() efivarfs: Revert "allow creation of zero length files" x86/efi/mixed: Move mixed mode startup code into libstub x86/efi/mixed: Simplify and document thunking logic x86/efi/mixed: Remove dependency on legacy startup_32 code x86/efi/mixed: Set up 1:1 mapping of lower 4GiB in the stub x86/efi/mixed: Factor out and clean up long mode entry x86/efi/mixed: Check CPU compatibility without relying on verify_cpu() x86/efistub: Merge PE and handover entrypoints
2025-03-14efi/libstub: Avoid legacy decompressor zlib/zstd wrappersArd Biesheuvel
Remove EFI zboot's dependency on the decompression wrappers used by the legacy decompressor boot code, which can only process the input in one go, and this will not work for upcoming support for embedded ELF images. They also do some odd things like providing a barebones malloc() implementation, which is not needed in a hosted environment such as the EFI boot services. So instead, implement GZIP deflate and ZSTD decompression in terms of the underlying libraries. Support for other compression algoritms has already been dropped. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-03-14efi/libstub: Avoid physical address 0x0 when doing random allocationArd Biesheuvel
Ben reports spurious EFI zboot failures on a system where physical RAM starts at 0x0. When doing random memory allocation from the EFI stub on such a platform, a random seed of 0x0 (which means no entropy source is available) will result in the allocation to be placed at address 0x0 if sufficient space is available. When this allocation is subsequently passed on to the decompression code, the 0x0 address is mistaken for NULL and the code complains and gives up. So avoid address 0x0 when doing random allocation, and set the minimum address to the minimum alignment. Cc: <stable@vger.kernel.org> Reported-by: Ben Schneider <ben@bens.haus> Tested-by: Ben Schneider <ben@bens.haus> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-03-13efi/libstub: Avoid CopyMem/SetMem EFI services after ExitBootServicesArd Biesheuvel
Given that memset/memcpy are intrinsics, the compiler might insert calls to these routines unexpectedly, including in code that executes after ExitBootServices(). In this case, the respective boot services are no longer accessible, and calling them will cause a crash. So fall back to a bytewise copy/store if this happens to occur, even though no such occurrences are known to exist in the kernel currently. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-03-07Merge branch 'x86-mixed-mode' into efi/nextArd Biesheuvel
2025-02-21x86/efi/mixed: Move mixed mode startup code into libstubArd Biesheuvel
The EFI mixed mode code has been decoupled from the legacy decompressor, in order to be able to reuse it with generic EFI zboot images for x86. Move the source file into the libstub source directory to facilitate this. Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-02-21x86/efistub: Merge PE and handover entrypointsArd Biesheuvel
The difference between the PE and handover entrypoints in the EFI stub is that the former allocates a struct boot_params whereas the latter expects one from the caller. Currently, these are two completely separate entrypoints, duplicating some logic and both relying of efi_exit() to return straight back to the firmware on an error. Simplify this by making the PE entrypoint call the handover entrypoint with NULL as the argument for the struct boot_params parameter. This makes the code easier to follow, and removes the need to support two different calling conventions in the mixed mode asm code. While at it, move the assignment of boot_params_ptr into the function that actually calls into the legacy decompressor, which is where its value is required. Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-02-04efi: Avoid cold plugged memory for placing the kernelArd Biesheuvel
UEFI 2.11 introduced EFI_MEMORY_HOT_PLUGGABLE to annotate system memory regions that are 'cold plugged' at boot, i.e., hot pluggable memory that is available from early boot, and described as system RAM by the firmware. Existing loaders and EFI applications running in the boot context will happily use this memory for allocating data structures that cannot be freed or moved at runtime, and this prevents the memory from being unplugged. Going forward, the new EFI_MEMORY_HOT_PLUGGABLE attribute should be tested, and memory annotated as such should be avoided for such allocations. In the EFI stub, there are a couple of occurrences where, instead of the high-level AllocatePages() UEFI boot service, a low-level code sequence is used that traverses the EFI memory map and carves out the requested number of pages from a free region. This is needed, e.g., for allocating as low as possible, or for allocating pages at random. While AllocatePages() should presumably avoid special purpose memory and cold plugged regions, this manual approach needs to incorporate this logic itself, in order to prevent the kernel itself from ending up in a hot unpluggable region, preventing it from being unplugged. So add the EFI_MEMORY_HOTPLUGGABLE macro definition, and check for it where appropriate. Cc: stable@vger.kernel.org Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-22efi: libstub: Use '-std=gnu11' to fix build with GCC 15Nathan Chancellor
GCC 15 changed the default C standard version to C23, which should not have impacted the kernel because it requests the gnu11 standard via '-std=' in the main Makefile. However, the EFI libstub Makefile uses its own set of KBUILD_CFLAGS for x86 without a '-std=' value (i.e., using the default), resulting in errors from the kernel's definitions of bool, true, and false in stddef.h, which are reserved keywords under C23. ./include/linux/stddef.h:11:9: error: expected identifier before ‘false’ 11 | false = 0, ./include/linux/types.h:35:33: error: two or more data types in declaration specifiers 35 | typedef _Bool bool; Set '-std=gnu11' in the x86 cflags to resolve the error and consistently use the same C standard version for the entire kernel. All other architectures reuse KBUILD_CFLAGS from the rest of the kernel, so this issue is not visible for them. Cc: stable@vger.kernel.org Reported-by: Kostadin Shishmanov <kostadinshishmanov@protonmail.com> Closes: https://lore.kernel.org/4OAhbllK7x4QJGpZjkYjtBYNLd_2whHx9oFiuZcGwtVR4hIzvduultkgfAIRZI3vQpZylu7Gl929HaYFRGeMEalWCpeMzCIIhLxxRhq4U-Y=@protonmail.com/ Reported-by: Jakub Jelinek <jakub@redhat.com> Closes: https://lore.kernel.org/Z4467umXR2PZ0M1H@tucnak/ Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-14efi/libstub: Use __free() helper for pool deallocationsArd Biesheuvel
Annotate some local buffer allocations as __free(efi_pool) and simplify the associated error handling accordingly. This removes a couple of gotos and simplifies the code. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-14efi/libstub: Use cleanup helpers for freeing copies of the memory mapArd Biesheuvel
The EFI stub may obtain the memory map from the firmware numerous times, and this involves doing a EFI pool allocation first, which needs to be freed after use. Streamline this using a cleanup helper, which makes the code easier to follow. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-14efi/libstub: Simplify PCI I/O handle buffer traversalArd Biesheuvel
Use LocateHandleBuffer() and a __free() cleanup helper to simplify the PCI I/O handle buffer traversal code. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-14efi/libstub: Refactor and clean up GOP resolution picker codeArd Biesheuvel
The EFI stub implements various ways of setting the resolution of the EFI framebuffer at boot, and this duplicates a lot of boilerplate for iterating over the supported modes and extracting the resolution and color depth. Refactor this into a single helper that takes a callback, and use it for the 'auto', 'list' and 'res' selection methods. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-14efi/libstub: Simplify GOP handling codeArd Biesheuvel
Use the LocateHandleBuffer() API and a __free() function to simplify the logic that allocates a handle buffer to iterate over all GOP protocols in the EFI database. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-14efi/libstub: Use C99-style for loop to traverse handle bufferArd Biesheuvel
Tweak the for_each_efi_handle() macro in order to avoid the need on the part of the caller to provide a loop counter variable. Also move efi_get_handle_num() to the callers, so that each occurrence can be replaced with the actual number returned by the simplified LocateHandleBuffer API. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2025-01-14x86/efistub: Drop long obsolete UGA supportArd Biesheuvel
UGA is the EFI graphical output protocol that preceded GOP, and has been long obsolete. Drop support for it from the x86 implementation of the EFI stub - other architectures never bothered to implement it (save for ia64) Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-12-19efi/libstub: Bump up EFI_MMAP_NR_SLACK_SLOTS to 32Hamza Mahfooz
Recent platforms require more slack slots than the current value of EFI_MMAP_NR_SLACK_SLOTS, otherwise they fail to boot. The current workaround is to append `efi=disable_early_pci_dma` to the kernel's cmdline. So, bump up EFI_MMAP_NR_SLACK_SLOTS to 32 to allow those platforms to boot with the aforementioned workaround. Signed-off-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Allen Pais <apais@linux.microsoft.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-12-06efi/zboot: Limit compression options to GZIP and ZSTDArd Biesheuvel
For historical reasons, the legacy decompressor code on various architectures supports 7 different compression types for the compressed kernel image. EFI zboot is not a compression library museum, and so the options can be limited to what is likely to be useful in practice: - GZIP is tried and tested, and is still one of the fastest at decompression time, although the compression ratio is not very high; moreover, Fedora is already shipping EFI zboot kernels for arm64 that use GZIP, and QEMU implements direct support for it when booting a kernel without firmware loaded; - ZSTD has a very high compression ratio (although not the highest), and is almost as fast as GZIP at decompression time. Reducing the number of options makes it less of a hassle for other consumers of the EFI zboot format (such as QEMU today, and kexec in the future) to support it transparently without having to carry 7 different decompression libraries. Acked-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-11-17efi/libstub: Take command line overrides into account for loaded filesArd Biesheuvel
When CONFIG_CMDLINE_OVERRIDE or CONFIG_CMDLINE_FORCE are configured, the command line provided by the boot stack should be ignored, and only the built-in command line should be taken into account. Add the required handling of this when dealing with initrd= or dtb= command line options in the EFI stub. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>