Re: [PATCH 1/2] x86/stacktrace: do not fail when regs on stack for ORC

[Jiri Slaby]

On 05/11/2018, 05:12 PM, Josh Poimboeuf wrote:
> I assume you're going to carry this as
> part of your patches to enable HAVE_RELIABLE_STACKTRACE?

Sure.

> --- a/tools/objtool/orc_dump.c
> +++ b/tools/objtool/orc_dump.c
> @@ -203,7 +203,8 @@ int orc_dump(const char *_objname)
>  
>               print_reg(orc[i].bp_reg, orc[i].bp_offset);
>  
> -             printf(" type:%s\n", orc_type_name(orc[i].type));
> +             printf(" type:%s end:%d\n",
> +                    orc_type_name(orc[i].type), orc[i].end);

Maybe just " type:%s%s\n" and »orc[i].end ? " END" : ""«?

>       }
>  
>       elf_end(elf);
> diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c
> index 18384d9be4e1..229c12e3fcf6 100644
> --- a/tools/objtool/orc_gen.c
> +++ b/tools/objtool/orc_gen.c
> @@ -86,6 +86,7 @@ int create_orc(struct objtool_file *file)
>               orc->sp_offset = cfa->offset;
>               orc->bp_offset = bp->offset;
>               orc->type = insn->state.type;
> +             orc->end = insn->state.end;

So you moved the assignment below of 'if (cfa->base == CFI_UNDEFINED)' –
this assignment will never happen, as I have just verified.

--- a/tools/objtool/orc_gen.c
+++ b/tools/objtool/orc_gen.c
@@ -31,6 +31,8 @@ int create_orc(struct objtool_file *file)
                struct cfi_reg *cfa = &insn->state.cfa;
                struct cfi_reg *bp = &insn->state.regs[CFI_BP];

+               orc->end = insn->state.end;
+
                if (cfa->base == CFI_UNDEFINED) {
                        orc->sp_reg = ORC_REG_UNDEFINED;
                        continue;
@@ -86,7 +88,6 @@ int create_orc(struct objtool_file *file)
                orc->sp_offset = cfa->offset;
                orc->bp_offset = bp->offset;
                orc->type = insn->state.type;
-               orc->end = insn->state.end;
        }

        return 0;


thanks,
-- 
js
suse labs