On Fri, Apr 16 2021 at 14:49, Sami Tolvanen wrote: > On Fri, Apr 16, 2021 at 2:18 PM Borislav Petkov <b...@alien8.de> wrote: >> In file included from ./include/linux/ftrace.h:22:0, >> from ./include/linux/init_task.h:9, >> from init/init_task.c:2: >> ./include/linux/ftrace.h: In function ‘ftrace_init_nop’: >> ./arch/x86/include/asm/ftrace.h:9:40: error: implicit declaration of >> function ‘function_nocfi’ [-Werror=implicit-function-declaration] > > This is defined in linux-next, but I do see another issue, which I'll > fix in v2. Note that CFI_CLANG itself cannot be selected on 32-bit > x86.
Sure and because of that it's overrated to make sure that it does not break the build. I know, sekurity ... But aside of that when looking at the rest of the series, then I really have to ask whether the only way to address this is to make a large amount of code unreadable like this: - wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64); + wrmsrl(MSR_LSTAR, (unsigned long)function_nocfi(entry_SYSCALL_64)); plus a gazillion of similar changes. This is unreadable garbage. Thanks, tglx