# Build linux kernel ### Get a copy of source code Take a copy of the linux kernel source repository via `git` software ``` git clone --depth=1 https://github.com/torvalds/linux ``` or download a zip file from this link - ### Generate `.config` file ``` make menuconfig ``` #### menuconfig options Here are the images of the some menuconfig options chosen. ![menuconfig](/files/RIUHdJ1Pw0QjoCdK2xgG) ![Options](/files/hOxKxCWdjxL4uCVQby9T) ![kernel .config support](/files/oLNHDoXzUJkc9Fa5fhYU) ![Module unloading](/files/FU3CFgDt3uv6iwpCZqN0) ![Kernel Function Tracer](/files/zoDjdkKFqRutqMBwLpNJ) Run `make help` to get the hints and options for building. ### build a image After that do, `make bzImage`. ```bash /workspace/linux (master) $ make bzImage SYSHDR arch/x86/include/generated/uapi/asm/unistd_32.h ... GZIP arch/x86/boot/compressed/vmlinux.bin.gz HOSTCC arch/x86/boot/compressed/mkpiggy MKPIGGY arch/x86/boot/compressed/piggy.S AS arch/x86/boot/compressed/piggy.o CC arch/x86/boot/compressed/cpuflags.o CC arch/x86/boot/compressed/early_serial_console.o CC arch/x86/boot/compressed/kaslr.o CC arch/x86/boot/compressed/ident_map_64.o CC arch/x86/boot/compressed/idt_64.o AS arch/x86/boot/compressed/idt_handlers_64.o AS arch/x86/boot/compressed/mem_encrypt.o CC arch/x86/boot/compressed/pgtable_64.o CC arch/x86/boot/compressed/acpi.o AS arch/x86/boot/compressed/efi_thunk_64.o LD arch/x86/boot/compressed/vmlinux ZOFFSET arch/x86/boot/zoffset.h AS arch/x86/boot/header.o CC arch/x86/boot/main.o CC arch/x86/boot/memory.o CC arch/x86/boot/pm.o AS arch/x86/boot/pmjump.o CC arch/x86/boot/printf.o CC arch/x86/boot/regs.o CC arch/x86/boot/string.o CC arch/x86/boot/tty.o CC arch/x86/boot/video.o CC arch/x86/boot/video-mode.o CC arch/x86/boot/version.o CC arch/x86/boot/video-vga.o CC arch/x86/boot/video-vesa.o CC arch/x86/boot/video-bios.o LD arch/x86/boot/setup.elf OBJCOPY arch/x86/boot/setup.bin OBJCOPY arch/x86/boot/vmlinux.bin HOSTCC arch/x86/boot/tools/build BUILD arch/x86/boot/bzImage Kernel: arch/x86/boot/bzImage is ready (#1) /workspace/linux (master) $ ``` Note **Kernel: arch/x86/boot/bzImage is ready (#1)**. ### Errors fatal error: libelf.h: No such file or directory ```bash /workspace/linux (master) $ make SYSHDR arch/x86/include/generated/uapi/asm/unistd_32.h ... DESCEND objtool :1:10: fatal error: libelf.h: No such file or directory compilation terminated. HOSTCC /workspace/linux/tools/objtool/fixdep.o ... AR /workspace/linux/tools/objtool/libsubcmd.a CC /workspace/linux/tools/objtool/arch/x86/special.o In file included from /workspace/linux/tools/objtool/include/objtool/objtool.h:13, from /workspace/linux/tools/objtool/include/objtool/arch.h:11, from /workspace/linux/tools/objtool/include/objtool/check.h:11, from /workspace/linux/tools/objtool/include/objtool/special.h:10, from arch/x86/special.c:4: /workspace/linux/tools/objtool/include/objtool/elf.h:10:10: fatal error: gelf.h: No such file or directory 10 | #include | ^~~~~~~~ compilation terminated. make[4]: *** [/workspace/linux/tools/build/Makefile.build:97: /workspace/linux/tools/objtool/arch/x86/special.o] Error 1 make[3]: *** [/workspace/linux/tools/build/Makefile.build:139: arch/x86] Error 2 make[2]: *** [Makefile:56: /workspace/linux/tools/objtool/objtool-in.o] Error 2 make[1]: *** [Makefile:69: objtool] Error 2 make: *** [Makefile:1337: tools/objtool] Error 2 ``` Install `libelf-dev` package ``` /workspace/linux (master) $ make bzImage SYNC include/config/auto.conf.cmd LEX scripts/kconfig/lexer.lex.c YACC scripts/kconfig/parser.tab.[ch] HOSTCC scripts/kconfig/lexer.lex.o HOSTCC scripts/kconfig/menu.o HOSTCC scripts/kconfig/parser.tab.o HOSTCC scripts/kconfig/preprocess.o HOSTCC scripts/kconfig/symbol.o HOSTCC scripts/kconfig/util.o HOSTLD scripts/kconfig/conf * * Restart config... * * * Control Group support * Control Group support (CGROUPS) [Y/n/?] y Favor dynamic modification latency reduction by default (CGROUP_FAVOR_DYNMODS) [N/y/?] (NEW) y ``` aa ``` /workspace/linux (master) $ make bzImage SYNC include/config/auto.conf.cmd LEX scripts/kconfig/lexer.lex.c YACC scripts/kconfig/parser.tab.[ch] HOSTCC scripts/kconfig/lexer.lex.o HOSTCC scripts/kconfig/menu.o HOSTCC scripts/kconfig/parser.tab.o HOSTCC scripts/kconfig/preprocess.o HOSTCC scripts/kconfig/symbol.o HOSTCC scripts/kconfig/util.o HOSTLD scripts/kconfig/conf * * Restart config... * * * Control Group support * Control Group support (CGROUPS) [Y/n/?] y Favor dynamic modification latency reduction by default (CGROUP_FAVOR_DYNMODS) [N/y/?] (NEW) y ``` ## Video {% embed url="" %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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