From 08f87a93c8ec709698edba66a5167077181fc978 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 8 Mar 2022 16:30:54 +0100 Subject: objtool: Validate IBT assumptions Intel IBT requires that every indirect JMP/CALL targets an ENDBR instructions, failing this #CP happens and we die. Similarly, all exception entries should be ENDBR. Find all code relocations and ensure they're either an ENDBR instruction or ANNOTATE_NOENDBR. For the exceptions look for UNWIND_HINT_IRET_REGS at sym+0 not being ENDBR. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154319.705110141@infradead.org --- tools/objtool/builtin-check.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'tools/objtool/builtin-check.c') diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index 5c2fcaa2c260..fc6975ab8b06 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -20,7 +20,8 @@ #include bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, - lto, vmlinux, mcount, noinstr, backup, sls, dryrun; + lto, vmlinux, mcount, noinstr, backup, sls, dryrun, + ibt; static const char * const check_usage[] = { "objtool check [] file.o", @@ -47,6 +48,7 @@ const struct option check_options[] = { OPT_BOOLEAN('B', "backup", &backup, "create .orig files before modification"), OPT_BOOLEAN('S', "sls", &sls, "validate straight-line-speculation"), OPT_BOOLEAN(0, "dry-run", &dryrun, "don't write the modifications"), + OPT_BOOLEAN(0, "ibt", &ibt, "validate ENDBR placement"), OPT_END(), }; -- cgit v1.2.3