2598ac6ec4
The 0-day bot reports that arm64 builds with CONFIG_CFI_CLANG + CONFIG_FTRACE are broken when CONFIG_FUNCTION_GRAPH_TRACER is not enabled: ld.lld: error: undefined symbol: __kcfi_typeid_ftrace_stub_graph >>> referenced by entry-ftrace.S:299 (arch/arm64/kernel/entry-ftrace.S:299) >>> arch/arm64/kernel/entry-ftrace.o:(.text+0x48) in archive vmlinux.a This is caused by ftrace_stub_graph using SYM_TYPE_FUNC_START when the address of the function is not taken in any C translation unit. Fix the build by only defining ftrace_stub_graph when it's actually needed, i.e. with CONFIG_FUNCTION_GRAPH_TRACER. Link: https://lore.kernel.org/lkml/202210251659.tRMs78RH-lkp@intel.com/ Fixes: 883bbbffa5a4 ("ftrace,kcfi: Separate ftrace_stub() and ftrace_stub_graph()") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20221109192831.3057131-1-samitolvanen@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.