Changes in Makefile.postlink

ac4f0678 - kbuild: Create intermediate vmlinux build with relocations preserved

Tue, 11 Mar 2025 11:06:20 +0000

kbuild: Create intermediate vmlinux build with relocations preservedThe imperative paradigm used to build vmlinux, extract some info from itor perform some checks on it, and subsequently modify it again goesagainst the declarative paradigm that is usually employed for definingmake rules.In particular, the Makefile.postlink files that consume their input viaan output rule result in some dodgy logic in the decompressor makefilesfor RISC-V and x86, given that the vmlinux.relocs input file needed togenerate the arch-specific relocation tables may not exist or be out ofdate, but cannot be constructed using the ordinary Make dependency basedrules, because the info needs to be extracted while vmlinux is in itsephemeral, non-stripped form.So instead, for architectures that require the static relocations thatare emitted into vmlinux when passing --emit-relocs to the linker, andare subsequently stripped out again, introduce an intermediate vmlinuxtarget called vmlinux.unstripped, and organize the reset of the buildlogic accordingly:- vmlinux.unstripped is created only once, and not updated again- build rules under arch/*/boot can depend on vmlinux.unstripped without running the risk of the data disappearing or being out of date- the final vmlinux generated by the build is not bloated with static relocations that are never needed again after the build completes.Signed-off-by: Ard Biesheuvel Signed-off-by: Masahiro Yamada List of files: /linux-6.15/arch/riscv/Makefile.postlink

71d815bf - kbuild: Strip runtime const RELA sections correctly

Mon, 13 Jan 2025 15:53:07 +0000

kbuild: Strip runtime const RELA sections correctlyDue to the fact that runtime const ELF sections are named without aleading period or double underscore, the RSTRIP logic that removes thestatic RELA sections from vmlinux fails to identify them. This resultsin a situation like below, where some sections that were supposed to getremoved are left behind. [Nr] Name Type Address Off Size ES Flg Lk Inf Al [58] runtime_shift_d_hash_shift PROGBITS ffffffff83500f50 2900f50 000014 00 A 0 0 1 [59] .relaruntime_shift_d_hash_shift RELA 0000000000000000 55b6f00 000078 18 I 70 58 8 [60] runtime_ptr_dentry_hashtable PROGBITS ffffffff83500f68 2900f68 000014 00 A 0 0 1 [61] .relaruntime_ptr_dentry_hashtable RELA 0000000000000000 55b6f78 000078 18 I 70 60 8 [62] runtime_ptr_USER_PTR_MAX PROGBITS ffffffff83500f80 2900f80 000238 00 A 0 0 1 [63] .relaruntime_ptr_USER_PTR_MAX RELA 0000000000000000 55b6ff0 000d50 18 I 70 62 8So tweak the match expression to strip all sections starting with .rel.While at it, consolidate the logic used by RISC-V, s390 and x86 into asingle shared Makefile library command.Link: https://lore.kernel.org/all/CAHk-=wjk3ynjomNvFN8jf9A1k=qSc=JFF591W00uXj-qqNUxPQ@mail.gmail.com/Signed-off-by: Ard Biesheuvel Reviewed-by: Charlie Jenkins Tested-by: Charlie Jenkins Tested-by: Alexander Gordeev Signed-off-by: Masahiro Yamada List of files: /linux-6.15/arch/riscv/Makefile.postlink

7f6d8f7e - kbuild: remove ARCH_POSTLINK from module builds

Wed, 18 Oct 2023 15:19:47 +0000

kbuild: remove ARCH_POSTLINK from module buildsThe '%.ko' rule in arch/*/Makefile.postlink does nothing but call the'true' command.Remove the unneeded code.Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier List of files: /linux-6.15/arch/riscv/Makefile.postlink

559d1e45 - riscv: Use --emit-relocs in order to move .rela.dyn in init

Wed, 29 Mar 2023 04:53:29 +0000

riscv: Use --emit-relocs in order to move .rela.dyn in initTo circumvent an issue where placing the relocations inside the initsections produces empty relocations, use --emit-relocs. But to avoidcarrying those relocations in vmlinux, use an intermediatevmlinux.relocs file which is a copy of vmlinux *before* stripping itsrelocations.Suggested-by: Björn Töpel Suggested-by: Nick Desaulniers Signed-off-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20230329045329.64565-7-alexghiti@rivosinc.comSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/Makefile.postlink

c2dea0bc - riscv: Check relocations at compile time

Wed, 29 Mar 2023 04:53:28 +0000

riscv: Check relocations at compile timeRelocating kernel at runtime is done very early in the boot process, soit is not convenient to check for relocations there and react in case arelocation was not expected.There exists a script in scripts/ that extracts the relocations fromvmlinux that is then used at postlink to check the relocations.Signed-off-by: Alexandre Ghiti Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20230329045329.64565-6-alexghiti@rivosinc.comSigned-off-by: Palmer Dabbelt List of files: /linux-6.15/arch/riscv/Makefile.postlink