On Fri, Jan 15, 2021 at 5:51 AM Sedat Dilek <sedat.di...@gmail.com> wrote: > > On Thu, Jan 14, 2021 at 8:40 PM Josh Poimboeuf <jpoim...@redhat.com> wrote: > > > > Add support for proper vmlinux.o validation, which will be needed for > > Sami's upcoming x86 LTO set. (And vmlinux validation is the future for > > objtool anyway, for other reasons.) > > > > This isn't 100% done -- most notably, crypto still needs to be supported > > -- but I think this gets us most of the way there. > > > > This can also be found at > > > > git://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linux.git > > objtool-vmlinux > > > > And for more testing it can be combined with Sami's x86 LTO patches: > > > > https://github.com/samitolvanen/linux clang-lto > > > > > > > > Josh Poimboeuf (21): > > objtool: Fix seg fault in BT_FUNC() with fake jump > > objtool: Fix error handling for STD/CLD warnings > > objtool: Fix retpoline detection in asm code > > objtool: Fix ".cold" section suffix check for newer versions of GCC > > objtool: Support retpoline jump detection for vmlinux.o > > x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub > > objtool: Assume only ELF functions do sibling calls > > objtool: Add asm version of STACK_FRAME_NON_STANDARD > > objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNC > > objtool: Add xen_start_kernel() to noreturn list > > objtool: Move unsuffixed symbol conversion to a helper function > > objtool: Add CONFIG_CFI_CLANG support > > x86/xen: Support objtool validation in xen-asm.S > > x86/xen: Support objtool vmlinux.o validation in xen-head.S > > x86/xen/pvh: Convert indirect jump to retpoline > > x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.S > > x86/acpi: Convert indirect jump to retpoline > > x86/acpi: Support objtool validation in wakeup_64.S > > x86/power: Convert indirect jumps to retpolines > > x86/power: Move restore_registers() to top of the file > > x86/power: Support objtool validation in hibernate_asm_64.S > > > > arch/x86/include/asm/unwind_hints.h | 13 +--- > > arch/x86/kernel/acpi/Makefile | 1 - > > arch/x86/kernel/acpi/wakeup_64.S | 5 +- > > arch/x86/kernel/ftrace_64.S | 8 +-- > > arch/x86/lib/retpoline.S | 2 +- > > arch/x86/platform/pvh/head.S | 3 +- > > arch/x86/power/Makefile | 1 - > > arch/x86/power/hibernate_asm_64.S | 105 ++++++++++++++-------------- > > arch/x86/xen/Makefile | 1 - > > arch/x86/xen/xen-asm.S | 29 +++++--- > > arch/x86/xen/xen-head.S | 5 +- > > include/linux/objtool.h | 13 +++- > > tools/include/linux/objtool.h | 13 +++- > > tools/objtool/arch/x86/decode.c | 4 +- > > tools/objtool/arch/x86/special.c | 2 +- > > tools/objtool/check.c | 91 +++++++++++++----------- > > tools/objtool/check.h | 12 +++- > > tools/objtool/elf.c | 87 +++++++++++++++++------ > > tools/objtool/elf.h | 2 +- > > 19 files changed, 241 insertions(+), 156 deletions(-) > > > > -- > > 2.29.2 > > > > I tried this series on top of clang-cfi and it segfaults here. > > + info OBJTOOL vmlinux.o > + [ != silent_ ] > + printf %-7s %s\n OBJTOOL vmlinux.o > OBJTOOL vmlinux.o > + tools/objtool/objtool orc generate --duplicate --mcount --vmlinux > --no-fp --no-unreachable --retpoline --uaccess vmlinux.o > Segmentation fault > + on_exit > + [ 139 -ne 0 ] > + cleanup > + rm -f .btf.* > + rm -f .tmp_System.map > + rm -f .tmp_initcalls.lds > + rm -f .tmp_symversions.lds > + rm -f .tmp_vmlinux* > + rm -f System.map > + rm -f vmlinux > + rm -f vmlinux.o > make[3]: *** [Makefile:1213: vmlinux] Error 139 >
I re-tried with the latest clang-lto Git and switched to Debian's LLVM-11.0.1. This build was successful. No objtool-vmlinux warnings observed. In the next step I try with my selfmade LLVM-11.1.0-rc1 (to see if it's broken). - Sedat
