From 799647ddb4c0ce1d7084fcf5b524e9a0c7728325 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Tue, 2 Dec 2025 15:01:17 -0800 Subject: objtool: Add more robust signal error handling, detect and warn about stack overflows When the kernel build fails due to an objtool segfault, the error message is a bit obtuse and confusing: make[5]: *** [scripts/Makefile.build:503: drivers/scsi/qla2xxx/qla2xxx.o] Error 139 ^^^^^^^^^ make[5]: *** Deleting file 'drivers/scsi/qla2xxx/qla2xxx.o' make[4]: *** [scripts/Makefile.build:556: drivers/scsi/qla2xxx] Error 2 make[3]: *** [scripts/Makefile.build:556: drivers/scsi] Error 2 make[2]: *** [scripts/Makefile.build:556: drivers] Error 2 make[1]: *** [/home/jpoimboe/git/linux/Makefile:2013: .] Error 2 make: *** [Makefile:248: __sub-make] Error 2 Add a signal handler to objtool which prints an error message like if the local stack has overflown (for which there's a chance as objtool makes heavy use of recursion): drivers/scsi/qla2xxx/qla2xxx.o: error: SIGSEGV: objtool stack overflow! or: drivers/scsi/qla2xxx/qla2xxx.o: error: SIGSEGV: objtool crash! Also, re-raise the signal so the core dump still gets triggered. [ mingo: Applied a build fix, added more comments and prettified the code. ] Suggested-by: Ingo Molnar Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Cc: Alexandre Chartre Cc: David Laight Cc: Linus Torvalds Cc: Nathan Chancellor Cc: Peter Zijlstra Link: https://patch.msgid.link/mi4tihk4dbncn7belrhp6ooudhpw4vdggerktu5333w3gqf3uf@vqlhc3y667mg --- tools/objtool/Build | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/objtool/Build') diff --git a/tools/objtool/Build b/tools/objtool/Build index 9982e665d58d..600da051af12 100644 --- a/tools/objtool/Build +++ b/tools/objtool/Build @@ -18,6 +18,7 @@ objtool-y += libstring.o objtool-y += libctype.o objtool-y += str_error_r.o objtool-y += librbtree.o +objtool-y += signal.o $(OUTPUT)libstring.o: ../lib/string.c FORCE $(call rule_mkdir) -- cgit v1.2.3