kernel/arch/arm/boot/compressed/vmlinux.lds.S, branch linux-6.19.y

kbuild: Split .modinfo out from ELF_DETAILS

2026-03-12T11:09:39Z

commit 8678591b47469fe16357234efef9b260317b8be4 upstream. Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") added .modinfo to ELF_DETAILS while removing it from COMMON_DISCARDS, as it was needed in vmlinux.unstripped and ELF_DETAILS was present in all architecture specific vmlinux linker scripts. While this shuffle is fine for vmlinux, ELF_DETAILS and COMMON_DISCARDS may be used by other linker scripts, such as the s390 and x86 compressed boot images, which may not expect to have a .modinfo section. In certain circumstances, this could result in a bootloader failing to load the compressed kernel [1]. Commit ddc6cbef3ef1 ("s390/boot/vmlinux.lds.S: Ensure bzImage ends with SecureBoot trailer") recently addressed this for the s390 bzImage but the same bug remains for arm, parisc, and x86. The presence of .modinfo in the x86 bzImage was the root cause of the issue worked around with commit d50f21091358 ("kbuild: align modinfo section for Secureboot Authenticode EDK2 compat"). misc.c in arch/x86/boot/compressed includes lib/decompress_unzstd.c, which in turn includes lib/xxhash.c and its MODULE_LICENSE / MODULE_DESCRIPTION macros due to the STATIC definition. Split .modinfo out from ELF_DETAILS into its own macro and handle it in all vmlinux linker scripts. Discard .modinfo in the places where it was previously being discarded from being in COMMON_DISCARDS, as it has never been necessary in those uses. Cc: stable@vger.kernel.org Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") Reported-by: Ed W Closes: https://lore.kernel.org/587f25e0-a80e-46a5-9f01-87cb40cfa377@wildgooses.com/ [1] Tested-by: Ed W # x86_64 Link: https://patch.msgid.link/20260225-separate-modinfo-from-elf-details-v1-1-387ced6baf4b@kernel.org Signed-off-by: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION

2024-06-10T11:01:33Z

The current arm32 architecture does not yet support the HAVE_LD_DEAD_CODE_DATA_ELIMINATION feature. arm32 is widely used in embedded scenarios, and enabling this feature would be beneficial for reducing the size of the kernel image. In order to make this work, we keep the necessary tables by annotating them with KEEP, also it requires further changes to linker script to KEEP some tables and wildcard compiler generated sections into the right place. When using ld.lld for linking, KEEP is not recognized within the OVERLAY command, and Ard proposed a concise method to solve this problem. It boots normally with defconfig, vexpress_defconfig and tinyconfig. The size comparison of zImage is as follows: defconfig vexpress_defconfig tinyconfig 5137712 5138024 424192 no dce 5032560 4997824 298384 dce 2.0% 2.7% 29.7% shrink When using smaller config file, there is a significant reduction in the size of the zImage. We also tested this patch on a commercially available single-board computer, and the comparison is as follows: a15eb_config 2161384 no dce 2092240 dce 3.2% shrink The zImage size has been reduced by approximately 3.2%, which is 70KB on 2.1M. Signed-off-by: Yuntao Liu Tested-by: Arnd Bergmann Reviewed-by: Arnd Bergmann Reviewed-by: Linus Walleij Signed-off-by: Russell King (Oracle)

ARM: decompressor: Include .data.rel.ro.local

2022-09-22T03:16:14Z

The .data.rel.ro.local section has the same semantics as .data.rel.ro here, so include it in the .rodata section of the decompressor. Additionally since the .printk_index section isn't usable outside of the core kernel, discard it in the decompressor. Avoids these warnings: arm-linux-gnueabi-ld: warning: orphan section `.data.rel.ro.local' from `arch/arm/boot/compressed/fdt_rw.o' being placed in section `.data.rel.ro.local' arm-linux-gnueabi-ld: warning: orphan section `.printk_index' from `arch/arm/boot/compressed/fdt_rw.o' being placed in section `.printk_index' Reported-by: kernel test robot Link: https://lore.kernel.org/linux-mm/202209080545.qMIVj7YM-lkp@intel.com Cc: Russell King Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Kees Cook

Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

2020-10-20T16:18:31Z

Pull ARM updates from Russell King: - handle inexact watchpoint addresses (Douglas Anderson) - decompressor serial debug cleanups (Linus Walleij) - update L2 cache prefetch bits (Guillaume Tucker) - add text offset and malloc size to the decompressor kexec data * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: add malloc size to decompressor kexec size structure ARM: add TEXT_OFFSET to decompressor kexec image structure ARM: 9007/1: l2c: fix prefetch bits init in L2X0_AUX_CTRL using DT values ARM: 9010/1: uncompress: Print the location of appended DTB ARM: 9009/1: uncompress: Enable debug in head.S ARM: 9008/1: uncompress: Drop excess whitespace print ARM: 9006/1: uncompress: Wait for ready and busy in debug prints ARM: 9005/1: debug: Select flow control for all debug UARTs ARM: 9004/1: debug: Split waituart to CTS and TXRDY ARM: 9003/1: uncompress: Delete unused debug macros ARM: 8997/2: hw_breakpoint: Handle inexact watchpoint addresses

ARM: add malloc size to decompressor kexec size structure

2020-09-15T13:36:26Z

Add the required malloc size to the decompressor kexec size structure. Signed-off-by: Russell King

ARM: add TEXT_OFFSET to decompressor kexec image structure

2020-09-15T13:36:25Z

Add the TEXT_OFFSET to the decompressor's kexec image structure to kexec knows what offset to use. Signed-off-by: Russell King

arm/boot: Handle all sections explicitly

2020-09-01T08:03:18Z

In preparation for warning on orphan sections, use common macros for debug sections, discards, and text stubs. Add discards for unwanted .note, and .rel sections. Signed-off-by: Kees Cook Signed-off-by: Ingo Molnar Cc: Russell King Link: https://lore.kernel.org/r/20200821194310.3089815-21-keescook@chromium.org

Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

2020-06-01T22:36:32Z

Pull ARM updates from Russell King: - remove a now unnecessary usage of the KERNEL_DS for sys_oabi_epoll_ctl() - update my email address in a number of drivers - decompressor EFI updates from Ard Biesheuvel - module unwind section handling updates - sparsemem Kconfig cleanups - make act_mm macro respect THREAD_SIZE * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 8980/1: Allow either FLATMEM or SPARSEMEM on the multiplatform build ARM: 8979/1: Remove redundant ARCH_SPARSEMEM_DEFAULT setting ARM: 8978/1: mm: make act_mm() respect THREAD_SIZE ARM: decompressor: run decompressor in place if loaded via UEFI ARM: decompressor: move GOT into .data for EFI enabled builds ARM: decompressor: defer loading of the contents of the LC0 structure ARM: decompressor: split off _edata and stack base into separate object ARM: decompressor: move headroom variable out of LC0 ARM: 8976/1: module: allow arch overrides for .init section names ARM: 8975/1: module: fix handling of unwind init sections ARM: 8974/1: use SPARSMEM_STATIC when SPARSEMEM is enabled ARM: 8971/1: replace the sole use of a symbol with its definition ARM: 8969/1: decompressor: simplify libfdt builds Update rmk's email address in various drivers ARM: compat: remove KERNEL_DS usage in sys_oabi_epoll_ctl()

Merge tag 'efi-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-06-01T20:35:27Z

Pull EFI updates from Ingo Molnar: "The EFI changes for this cycle are: - preliminary changes for RISC-V - Add support for setting the resolution on the EFI framebuffer - Simplify kernel image loading for arm64 - Move .bss into .data via the linker script instead of relying on symbol annotations. - Get rid of __pure getters to access global variables - Clean up the config table matching arrays - Rename pr_efi/pr_efi_err to efi_info/efi_err, and use them consistently - Simplify and unify initrd loading - Parse the builtin command line on x86 (if provided) - Implement printk() support, including support for wide character strings - Simplify GDT handling in early mixed mode thunking code - Some other minor fixes and cleanups" * tag 'efi-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits) efi/x86: Don't blow away existing initrd efi/x86: Drop the special GDT for the EFI thunk efi/libstub: Add missing prototype for PE/COFF entry point efi/efivars: Add missing kobject_put() in sysfs entry creation error path efi/libstub: Use pool allocation for the command line efi/libstub: Don't parse overlong command lines efi/libstub: Use snprintf with %ls to convert the command line efi/libstub: Get the exact UTF-8 length efi/libstub: Use %ls for filename efi/libstub: Add UTF-8 decoding to efi_puts efi/printf: Add support for wchar_t (UTF-16) efi/gop: Add an option to list out the available GOP modes efi/libstub: Add definitions for console input and events efi/libstub: Implement printk-style logging efi/printf: Turn vsprintf into vsnprintf efi/printf: Abort on invalid format efi/printf: Refactor code to consolidate padding and output efi/printf: Handle null string input efi/printf: Factor out integer argument retrieval efi/printf: Factor out width/precision parsing ...

ARM: decompressor: move GOT into .data for EFI enabled builds

2020-05-19T16:23:22Z

We will be running the decompressor in place after a future patch, instead of copying it around first. This means we no longer have to disable and re-enable the MMU and caches either. However, this means we will be loaded with the restricted permissions set by the UEFI firmware, which means that we have to move the GOT table into the data section in order for the contents to be writable by the code itself. Signed-off-by: Ard Biesheuvel Reviewed-by: Nicolas Pitre