objtool: Always fail on fatal errors

Objtool writes several object annotations which are used to enable
critical kernel runtime functionalities like static calls and
retpoline/rethunk patching.

In the rare case where it fails to read or write an object, the
annotations don't get written, causing runtime code patching to fail and
code to become corrupted.

Due to the catastrophic nature of such warnings, convert them to errors
which fail the build regardless of CONFIG_OBJTOOL_WERROR.

Reported-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/7d35684ca61eac56eb2424f300ca43c5d257b170.1743481539.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/SJ1PR11MB61295789E25C2F5197EFF2F6B9A72@SJ1PR11MB6129.namprd11.prod.outlook.com

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index c8b3c8e7090c35b1319a100297e6db9f1c92dc60..cde669923b72fef2fbbe7b4d03295b41eb6d44e6 100644 (file)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -4753,6 +4753,9 @@ out:
        if (!ret && !warnings)
                return 0;
 
+       if (opts.werror && warnings)
+               ret = 1;
+
        if (opts.verbose) {
                if (opts.werror && warnings)
                        WARN("%d warning(s) upgraded to errors", warnings);
@@ -4760,15 +4763,5 @@ out:
                disas_warned_funcs(file);
        }
 
-       /*
-        * CONFIG_OBJTOOL_WERROR upgrades all warnings (and errors) to actual
-        * errors.
-        *
-        * Note that even fatal errors don't yet actually return an error
-        * without CONFIG_OBJTOOL_WERROR.  That will be fixed soon-ish.
-        */
-       if (opts.werror)
-               return 1;
-
-       return 0;
+       return ret;
 }