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| author | Peter Zijlstra <peterz@infradead.org> | 2018-01-31 12:18:28 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-02-21 11:05:05 +0300 |
| commit | ca41b97ed9124fd62323a162de5852f6e28f94b8 (patch) | |
| tree | 834e3ba681fc038c7570acf9fe7ae17991a981fe | |
| parent | b5bc2231b8ad4387c9641f235ca0ad8cd300b6df (diff) | |
| download | linux-ca41b97ed9124fd62323a162de5852f6e28f94b8.tar.xz | |
objtool: Add module specific retpoline rules
David allowed retpolines in .init.text, except for modules, which will
trip up objtool retpoline validation, fix that.
Requested-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | scripts/Makefile.build | 2 | ||||
| -rw-r--r-- | tools/objtool/builtin-check.c | 3 | ||||
| -rw-r--r-- | tools/objtool/builtin.h | 2 | ||||
| -rw-r--r-- | tools/objtool/check.c | 9 |
4 files changed, 14 insertions, 2 deletions
diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 53d862aee335..ce0fc4dd68c6 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -256,6 +256,8 @@ __objtool_obj := $(objtree)/tools/objtool/objtool objtool_args = $(if $(CONFIG_UNWINDER_ORC),orc generate,check) +objtool_args += $(if $(part-of-module), --module,) + ifndef CONFIG_FRAME_POINTER objtool_args += --no-fp endif diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index dd6bcd6097f5..694abc628e9b 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -29,7 +29,7 @@ #include "builtin.h" #include "check.h" -bool no_fp, no_unreachable, retpoline; +bool no_fp, no_unreachable, retpoline, module; static const char * const check_usage[] = { "objtool check [<options>] file.o", @@ -40,6 +40,7 @@ const struct option check_options[] = { OPT_BOOLEAN('f', "no-fp", &no_fp, "Skip frame pointer validation"), OPT_BOOLEAN('u', "no-unreachable", &no_unreachable, "Skip 'unreachable instruction' warnings"), OPT_BOOLEAN('r', "retpoline", &retpoline, "Validate retpoline assumptions"), + OPT_BOOLEAN('m', "module", &module, "Indicates the object will be part of a kernel module"), OPT_END(), }; diff --git a/tools/objtool/builtin.h b/tools/objtool/builtin.h index 7b6addfce045..28ff40e19a14 100644 --- a/tools/objtool/builtin.h +++ b/tools/objtool/builtin.h @@ -20,7 +20,7 @@ #include <subcmd/parse-options.h> extern const struct option check_options[]; -extern bool no_fp, no_unreachable, retpoline; +extern bool no_fp, no_unreachable, retpoline, module; extern int cmd_check(int argc, const char **argv); extern int cmd_orc(int argc, const char **argv); diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 5e5db7b4d77b..472e64e95891 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1958,6 +1958,15 @@ static int validate_retpoline(struct objtool_file *file) if (insn->retpoline_safe) continue; + /* + * .init.text code is ran before userspace and thus doesn't + * strictly need retpolines, except for modules which are + * loaded late, they very much do need retpoline in their + * .init.text + */ + if (!strcmp(insn->sec->name, ".init.text") && !module) + continue; + WARN_FUNC("indirect %s found in RETPOLINE build", insn->sec, insn->offset, insn->type == INSN_JUMP_DYNAMIC ? "jump" : "call"); |