user/sven/linux.git/scripts/link-vmlinux.sh, branch v6.10.6

kbuild: explicitly run mksysmap as sed script from link-vmlinux.sh

2024-06-06T23:42:14Z

In commit b18b047002b7 ("kbuild: change scripts/mksysmap into sed script"), the mksysmap script was transformed into a sed script, made directly executable with "#!/bin/sed -f". Apparently, the path to sed is different on NixOS. The shebang can't use the env command, otherwise the "sed -f" command would be treated as a single argument. This can be solved with the -S flag, but that is a GNU extension. Explicitly use sed instead of relying on the executable shebang to fix NixOS builds without breaking build environments using Busybox. Fixes: b18b047002b7 ("kbuild: change scripts/mksysmap into sed script") Reported-by: Kent Overstreet Signed-off-by: Richard Acayan Reviewed-by: Nathan Chancellor Tested-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: Masahiro Yamada

kbuild: remove a stale comment about cleaning in link-vmlinux.sh

2024-05-29T07:40:03Z

Remove the left-over of commit 51eb95e2da41 ("kbuild: Don't remove link-vmlinux temporary files on exit/signal"). Signed-off-by: Masahiro Yamada

kbuild: fix short log for AS in link-vmlinux.sh

2024-05-29T07:40:03Z

In convention, short logs print the output file, not the input file. Let's change the suffix for 'AS' since it assembles *.S into *.o. [Before] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.S LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.S LD vmlinux [After] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.o LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.o LD vmlinux Signed-off-by: Masahiro Yamada

kbuild: change scripts/mksysmap into sed script

2024-05-29T07:40:03Z

The previous commit removed the subshell execution from scripts/mksysmap, which is now simple enough to become a sed script. Signed-off-by: Masahiro Yamada

kbuild: avoid unneeded kallsyms step 3

2024-05-29T07:40:03Z

Since commit 951bcae6c5a0 ("kallsyms: Avoid weak references for kallsyms symbols"), the kallsyms step 3 always occurs. You can compare the build logs. [Before 951bcae6c5a0] $ git checkout 951bcae6c5a0^ $ make defconfig all [ snip ] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.S LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.S LD vmlinux [After 951bcae6c5a0] $ git checkout 951bcae6c5a0 $ make defconfig all [ snip ] LD .tmp_vmlinux.kallsyms1 NM .tmp_vmlinux.kallsyms1.syms KSYMS .tmp_vmlinux.kallsyms1.S AS .tmp_vmlinux.kallsyms1.S LD .tmp_vmlinux.kallsyms2 NM .tmp_vmlinux.kallsyms2.syms KSYMS .tmp_vmlinux.kallsyms2.S AS .tmp_vmlinux.kallsyms2.S LD .tmp_vmlinux.kallsyms3 # should not happen NM .tmp_vmlinux.kallsyms3.syms # should not happen KSYMS .tmp_vmlinux.kallsyms3.S # should not happen AS .tmp_vmlinux.kallsyms3.S # should not happen LD vmlinux The resulting vmlinux is correct, but it always requires an additional linking step. The symbols produced by kallsyms are excluded from kallsyms itself because they were previously missing in step 1. With those symbols excluded, the symbol lists matched between step 1 and step 2, eliminating the need for step 3. Now, this has a negative effect. Since 951bcae6c5a0, the PROVIDE() directives provide the fallback definitions, which are not trimmed from the sysbol list in step 1 because ${kallsymso_prev} is empty at this point. In step 2, ${kallsymso_prev} is set, and the kallsyms_* symbols are trimmed from the symbol list. Due to the table size difference between step 1 and step 2 (the former is larger due to the presence of kallsyms_*), step 3 is triggered. Now that the kallsyms_* symbols are always linked, let's stop omitting them from kallsyms. This avoids unnecessary step 3. Fixes: 951bcae6c5a0 ("kallsyms: Avoid weak references for kallsyms symbols") Signed-off-by: Masahiro Yamada

kbuild: Fix changing ELF file type for output of gen_btf for big endian

2024-02-14T21:56:40Z

Commit 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF") changed the ELF type of .btf.vmlinux.bin.o to ET_REL via dd, which works fine for little endian platforms: 00000000 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00 |.ELF............| -00000010 03 00 b7 00 01 00 00 00 00 00 00 80 00 80 ff ff |................| +00000010 01 00 b7 00 01 00 00 00 00 00 00 80 00 80 ff ff |................| However, for big endian platforms, it changes the wrong byte, resulting in an invalid ELF file type, which ld.lld rejects: 00000000 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 |.ELF............| -00000010 00 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| +00000010 01 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| Type: : 103 ld.lld: error: .btf.vmlinux.bin.o: unknown file type Fix this by updating the entire 16-bit e_type field rather than just a single byte, so that everything works correctly for all platforms and linkers. 00000000 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 |.ELF............| -00000010 00 03 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| +00000010 00 01 00 16 00 00 00 01 00 00 00 00 00 10 00 00 |................| Type: REL (Relocatable file) While in the area, update the comment to mention that binutils 2.35+ matches LLD's behavior of rejecting an ET_EXEC input, which occurred after the comment was added. Cc: stable@vger.kernel.org Fixes: 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF") Link: https://github.com/llvm/llvm-project/pull/75643 Suggested-by: Masahiro Yamada Signed-off-by: Nathan Chancellor Reviewed-by: Fangrui Song Reviewed-by: Nicolas Schier Reviewed-by: Kees Cook Reviewed-by: Justin Stitt Signed-off-by: Masahiro Yamada

Merge tag 'kbuild-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2023-04-30T18:32:53Z

Pull Kbuild updates from Masahiro Yamada: - Refactor scripts/kallsyms to make it faster and easier to maintain - Clean up menuconfig - Provide Clang with hard-coded target triple instead of CROSS_COMPILE - Use -z pack-relative-relocs flags instead of --use-android-relr-tags for arm64 CONFIG_RELR - Add srcdeb-pkg target to build only a Debian source package - Add KDEB_SOURCE_COMPRESS option to specify the compression for a Debian source package - Misc cleanups and fixes * tag 'kbuild-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: deb-pkg: specify targets in debian/rules as .PHONY sparc: unify sparc32/sparc64 archhelp kbuild: rpm-pkg: remove kernel-drm PROVIDES kbuild: deb-pkg: add KDEB_SOURCE_COMPRESS to specify source compression kbuild: add srcdeb-pkg target Makefile: use -z pack-relative-relocs kbuild: clang: do not use CROSS_COMPILE for target triple kconfig: menuconfig: reorder functions to remove forward declarations kconfig: menuconfig: remove unused M_EVENT macro kconfig: menuconfig: remove OLD_NCURSES macro kbuild: builddeb: Eliminate debian/arch use scripts/kallsyms: update the usage in the comment block scripts/kallsyms: decrease expand_symbol() / cleanup_symbol_name() calls scripts/kallsyms: change the output order scripts/kallsyms: move compiler-generated symbol patterns to mksysmap scripts/kallsyms: exclude symbols generated by itself dynamically scripts/mksysmap: use sed with in-line comments scripts/mksysmap: remove comments described in nm(1) scripts/kallsyms: remove redundant code for omitting U and N kallsyms: expand symbol name into comment for debugging

scripts/kallsyms: exclude symbols generated by itself dynamically

2023-04-17T02:03:56Z

Drop the symbols generated by scripts/kallsyms itself automatically instead of maintaining the symbol list manually. Pass the kallsyms object from the previous kallsyms step (if it exists) as the third parameter of scripts/mksysmap, which will weed out the generated symbols from the input to the next kallsyms step. Signed-off-by: Masahiro Yamada

scripts/link-vmlinux.sh: fix error message presentation

2023-04-08T20:45:37Z

This comes out as Try make KALLSYMS_EXTRA_PASS=1 as a workaround but we want quotes: Try "make KALLSYMS_EXTRA_PASS=1" as a workaround Link: https://lkml.kernel.org/r/202303042034.Cjc7JTd0-lkp@intel.com Cc: kernel test robot Signed-off-by: Andrew Morton

kallsyms: Correctly sequence symbols when CONFIG_LTO_CLANG=y

2022-11-13T02:47:36Z

LLVM appends various suffixes for local functions and variables, suffixes observed: - foo.llvm.[0-9a-f]+ - foo.[0-9a-f]+ Therefore, when CONFIG_LTO_CLANG=y, kallsyms_lookup_name() needs to truncate the suffix of the symbol name before comparing the local function or variable name. Old implementation code: - if (strcmp(namebuf, name) == 0) - return kallsyms_sym_address(i); - if (cleanup_symbol_name(namebuf) && strcmp(namebuf, name) == 0) - return kallsyms_sym_address(i); The preceding process is traversed by address from low to high. That is, for those with the same name after the suffix is removed, the one with the smallest address is returned first. Therefore, when sorting in the tool, if the raw names are the same, they should be sorted by address in ascending order. ASCII[.] = 2e ASCII[0-9] = 30,39 ASCII[A-Z] = 41,5a ASCII[_] = 5f ASCII[a-z] = 61,7a According to the preceding ASCII code values, the following sorting result is strictly followed. --------------------------------- | main-key | sub-key | |---------------------------------| | | addr_lowest | | | ... | | . | ... | | | addr_highest | |---------------------------------| | ? | | //? is [_A-Za-z0-9] --------------------------------- Signed-off-by: Zhen Lei Signed-off-by: Luis Chamberlain