On Fri, Feb 13, 2026 at 08:05:02PM -0500, Nicholas Vinson wrote:
> The i386-pc kernel image fails to build because of changes made to
> address ld.lld-21 and newer linking issues. Specifically, with
> ld.lld-21, if you try to set the text section address below image base
> address when linking a non-relocatable binary, ld.lld wil fail to link.
>
> Switching to using a customized linker script solves the issue and is a
> more robost solution to supporting multiple linkers than attempting to
> find a set of command-line flags that satisified all supported linkers
> and links the kernel properly. In the worst case, continued use of
> command-line flags could result in having to create code branches to
> support various linkers.
>
> For example, when dealing with just ld.bfd and ld.lld, the behavioral
> differences between the two made finding a proper subset of flags that
> worked impossible. The previous attempt dropped -Ttext for --image-base,
> which has been proven not to work. The simplest correction,
> -Wl,--image-base=0 -Wl,-Ttext, did not work because that option resulted
> in a GRUB kernel that entered into a tight infinite refresh loop.
>
> Moreover, ld.lld does not order the sections the same way ld.bfd does,
> and that results in object files with gaps or holes when sections are
> stripped. I suspect, but did not investigate, that this plays a role in
> the infinite refresh loop I mentioned earlier.
>
> The easiest way to resolve all this is to use customized linker scripts.
> These scripts, by default, override any default configuration the linker
> would otherwise impose, allow for complete control in aligning sections,
> and allows GRUB to specify where in the load segment each section goes.
>
> This change does require linkers to support the --defsym flag, which
> requires its argument to be of the form 'sym=address' as 'sym address'
> is not supported.
>
> Signed-off-by: Nicholas Vinson <[email protected]>
> ---
> conf/Makefile.extra-dist | 1 +
> conf/i386-pc-kernel.lds | 51 +++++++++++++++++++++++++++++++++++++
> grub-core/Makefile.core.def | 31 +++++++++++-----------
> 3 files changed, 68 insertions(+), 15 deletions(-)
> create mode 100644 conf/i386-pc-kernel.lds
>
> diff --git a/conf/Makefile.extra-dist b/conf/Makefile.extra-dist
> index d22b6c862..892df8208 100644
> --- a/conf/Makefile.extra-dist
> +++ b/conf/Makefile.extra-dist
> @@ -17,6 +17,7 @@ EXTRA_DIST += docs/grub.cfg
> EXTRA_DIST += docs/osdetect.cfg
>
> EXTRA_DIST += conf/i386-cygwin-img-ld.sc
> +EXTRA_DIST += conf/i386-pc-kernel.lds
>
> EXTRA_DIST += grub-core/Makefile.core.def
> EXTRA_DIST += grub-core/Makefile.gcry.def
> diff --git a/conf/i386-pc-kernel.lds b/conf/i386-pc-kernel.lds
> new file mode 100644
> index 000000000..d40c7736c
> --- /dev/null
> +++ b/conf/i386-pc-kernel.lds
> @@ -0,0 +1,51 @@
> +ENTRY(_start)
> +
> +/*
> + * Align sections to a 16-byte boundary. This guarantees ABI compatibility
> with
> + * C generated code
> + */
> +SECTION_ALIGN = 0x10;
> +
> +PHDRS {
> + text PT_LOAD FLAGS(7) /* PF_R | PF_W | PF_X */;
> +}
> +
> +SECTIONS
> +{
> + /*
> + * Set section alignment to 1. This allows sections to be aligned without
> + * creating holes in the VMA space or gaps in the file.
> + */
> + . = _grub_text_base;
> + .text ALIGN(0x1) : {
> + _start = .;
> + *(.text .text.*)
> + . = ALIGN(SECTION_ALIGN);
> + } :text
> + .rodata ALIGN(0x1) : {
> + *(.rodata .rodata.*)
> + . = ALIGN(SECTION_ALIGN);
> + } :text
> + .module_license ALIGN(0x1) : {
> + *(.module_license)
> + . = ALIGN(SECTION_ALIGN);
> + } :text
> + .data ALIGN(0x1) : {
> + *(.data .data.*)
> + . = ALIGN(SECTION_ALIGN);
> + _edata = .;
> + } :text
> + .bss ALIGN(0x1) : {
> + __bss_start = .;
> + *(.bss .bss.*)
> + *(COMMON)
> + . = ALIGN(SECTION_ALIGN);
> + _end = .;
> + } :text
> + /DISCARD/ : {
> + *(.interp)
> + *(.note*)
> + *(.comment)
> + *(.build-id)
> + }
> +}
> diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
> index 0cf155128..1a91e53d6 100644
> --- a/grub-core/Makefile.core.def
> +++ b/grub-core/Makefile.core.def
> @@ -10,6 +10,7 @@ transform_data = {
> installdir = noinst;
> name = genmod.sh;
> common = genmod.sh.in;
> + i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
I think everything below belongs to patch #7.
> };
>
> transform_data = {
> @@ -82,21 +83,21 @@ kernel = {
> riscv64_efi_stripflags = '--strip-unneeded -K start -R .note -R .comment
> -R .note.gnu.gold-version -R .eh_frame';
>
> i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_pc_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x9000';
> + i386_pc_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x9000';
> i386_qemu_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_qemu_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x9000';
> + i386_qemu_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x9000';
> i386_coreboot_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_coreboot_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x9000';
> + i386_coreboot_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x9000';
> i386_multiboot_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_multiboot_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x9000';
> + i386_multiboot_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x9000';
> i386_ieee1275_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_ieee1275_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x10000';
> + i386_ieee1275_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x10000';
> i386_xen_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_xen_ldflags = '$(TARGET_IMG_BASE_LDOPT),0';
> + i386_xen_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0';
> x86_64_xen_ldflags = '$(TARGET_IMG_LDFLAGS)';
> x86_64_xen_ldflags = '$(TARGET_IMG_BASE_LDOPT),0';
> i386_xen_pvh_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_xen_pvh_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x100000';
> + i386_xen_pvh_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x100000';
>
> mips_loongson_ldflags = '-Wl,-Ttext,0x80200000';
> powerpc_ieee1275_ldflags = '-Wl,-Ttext,0x200000';
> @@ -450,10 +451,10 @@ image = {
> sparc64_ieee1275 = boot/sparc64/ieee1275/boot.S;
>
> i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_pc_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x7C00';
> + i386_pc_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x7C00';
>
> i386_qemu_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_qemu_ldflags =
> '$(TARGET_IMG_BASE_LDOPT),$(GRUB_BOOT_MACHINE_LINK_ADDR)';
> + i386_qemu_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)$(GRUB_BOOT_MACHINE_LINK_ADDR)';
> i386_qemu_ccasflags =
> '-DGRUB_BOOT_MACHINE_LINK_ADDR=$(GRUB_BOOT_MACHINE_LINK_ADDR)';
>
> /* The entry point for a.out binaries on sparc64 starts
> @@ -478,7 +479,7 @@ image = {
> cppflags = '-DHYBRID_BOOT=1';
>
> i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_pc_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x7C00';
> + i386_pc_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x7C00';
>
> objcopyflags = '-O binary';
> enable = i386_pc;
> @@ -489,7 +490,7 @@ image = {
>
> i386_pc = boot/i386/pc/cdboot.S;
> i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_pc_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x7C00';
> + i386_pc_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x7C00';
>
> sparc64_ieee1275 = boot/sparc64/ieee1275/boot.S;
>
> @@ -509,7 +510,7 @@ image = {
> i386_pc = boot/i386/pc/pxeboot.S;
>
> i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_pc_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x7C00';
> + i386_pc_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x7C00';
>
> objcopyflags = '-O binary';
> enable = i386_pc;
> @@ -520,7 +521,7 @@ image = {
> i386_pc = boot/i386/pc/diskboot.S;
>
> i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_pc_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x8000';
> + i386_pc_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x8000';
>
> sparc64_ieee1275 = boot/sparc64/ieee1275/diskboot.S;
> sparc64_ieee1275_ldflags = '-Wl,-Ttext=0x4200';
> @@ -536,7 +537,7 @@ image = {
> i386_pc = boot/i386/pc/lnxboot.S;
>
> i386_pc_ldflags = '$(TARGET_IMG_LDFLAGS)';
> - i386_pc_ldflags = '$(TARGET_IMG_BASE_LDOPT),0x6000';
> + i386_pc_ldflags =
> '$(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x6000';
>
> objcopyflags = '-O binary';
> enable = i386_pc;
> @@ -578,7 +579,7 @@ image = {
> i386_pc_nodist = rs_decoder.h;
>
> objcopyflags = '-O binary';
> - ldflags = '$(TARGET_IMG_LDFLAGS) $(TARGET_IMG_BASE_LDOPT),0x8200';
> + ldflags = '$(TARGET_IMG_LDFLAGS)
> $(TARGET_IMG_BASE_LDOPT)$(TARGET_IMG_BASE_LDOPT_ARG_SEP)0x8200';
> enable = i386_pc;
> };
Daniel
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