| Message ID | 20230208164011.2287122-2-arnd@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/4] kasan: mark addr_has_metadata __always_inline | expand |
On Wed, 8 Feb 2023 at 17:40, Arnd Bergmann <arnd@kernel.org> wrote: > > From: Arnd Bergmann <arnd@arndb.de> > > objtool warns about some suspicous code inside of kmsan: > > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_n+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_n+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_1+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_1+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_2+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_2+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_4+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_4+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_load_8+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_metadata_ptr_for_store_8+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_instrument_asm_store+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_chain_origin+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_poison_alloca+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_warning+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: __msan_get_context_state+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_copy_to_user+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_unpoison_memory+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_unpoison_entry_regs+0x4: call to __fentry__() with UACCESS enabled > vmlinux.o: warning: objtool: kmsan_report+0x4: call to __fentry__() with UACCESS enabled > > Similar code already exists in kasan, which avoids this by skipping > ftrace annotations, so do the same thing here. > > Fixes: f80be4571b19 ("kmsan: add KMSAN runtime core") > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > mm/kmsan/Makefile | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/mm/kmsan/Makefile b/mm/kmsan/Makefile > index 98eab2856626..389fd767a11f 100644 > --- a/mm/kmsan/Makefile > +++ b/mm/kmsan/Makefile > @@ -16,6 +16,14 @@ CC_FLAGS_KMSAN_RUNTIME += -DDISABLE_BRANCH_PROFILING > > CFLAGS_REMOVE.o = $(CC_FLAGS_FTRACE) That means this CFLAGS_REMOVE.o didn't work, right? Can it be removed? > +# Disable ftrace to avoid recursion. > +CFLAGS_REMOVE_core.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_hooks.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_init.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_instrumentation.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_report.o = $(CC_FLAGS_FTRACE) > +CFLAGS_REMOVE_shadow.o = $(CC_FLAGS_FTRACE) > + > CFLAGS_core.o := $(CC_FLAGS_KMSAN_RUNTIME) > CFLAGS_hooks.o := $(CC_FLAGS_KMSAN_RUNTIME) > CFLAGS_init.o := $(CC_FLAGS_KMSAN_RUNTIME) > -- > 2.39.1 >
On Wed, Feb 8, 2023, at 18:00, Marco Elver wrote: >> CFLAGS_REMOVE.o = $(CC_FLAGS_FTRACE) > > That means this CFLAGS_REMOVE.o didn't work, right? Can it be removed? > Ah, I missed this. Adjusted the patch and description accordingly. Arnd
On Wed, Feb 8, 2023 at 8:32 PM Arnd Bergmann <arnd@arndb.de> wrote: > > On Wed, Feb 8, 2023, at 18:00, Marco Elver wrote: > > >> CFLAGS_REMOVE.o = $(CC_FLAGS_FTRACE) > > > > That means this CFLAGS_REMOVE.o didn't work, right? Can it be removed? > > > > Ah, I missed this. Adjusted the patch and description accordingly. > > Arnd Acked-by: Alexander Potapenko <glider@google.com> (assuming you did, b/c I couldn't find the new version)
diff --git a/mm/kmsan/Makefile b/mm/kmsan/Makefile index 98eab2856626..389fd767a11f 100644 --- a/mm/kmsan/Makefile +++ b/mm/kmsan/Makefile @@ -16,6 +16,14 @@ CC_FLAGS_KMSAN_RUNTIME += -DDISABLE_BRANCH_PROFILING CFLAGS_REMOVE.o = $(CC_FLAGS_FTRACE) +# Disable ftrace to avoid recursion. +CFLAGS_REMOVE_core.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_hooks.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_init.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_instrumentation.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_report.o = $(CC_FLAGS_FTRACE) +CFLAGS_REMOVE_shadow.o = $(CC_FLAGS_FTRACE) + CFLAGS_core.o := $(CC_FLAGS_KMSAN_RUNTIME) CFLAGS_hooks.o := $(CC_FLAGS_KMSAN_RUNTIME) CFLAGS_init.o := $(CC_FLAGS_KMSAN_RUNTIME)