Re: [GIT PULL] MM updates for 6.1-rc1
From: Josh Poimboeuf
Date: Tue Oct 11 2022 - 14:44:58 EST
On Tue, Oct 11, 2022 at 10:24:27AM +0200, Peter Zijlstra wrote:
> On Mon, Oct 10, 2022 at 06:20:00PM -0700, Linus Torvalds wrote:
> > The other thing I notice from just doing a build is that I now get
> > vmlinux.o: warning: objtool: kasan_report+0x12: call to
> > stackleak_track_stack() with UACCESS enabled
> So kasan_report() is already marked as being special; and it does the
> mandatory user_access_save() / user_access_restore() things to fix it
> But it looks like kasan code itself is now getting instrumented by the
> stackleak stuff and that inserts a call outside of the
> user_access_save()/restore() thing, and *that* is getting flagged.
> Looking at mm/kasan/Makefile it disables a lot of the instrumentation,
> but perhaps not enough?
I can recreate, but weirdly the below doesn't seem to fix it.
diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile
index d4837bff3b60..a41cf1235032 100644
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
KASAN_SANITIZE := n
+KMSAN_SANITIZE := n
UBSAN_SANITIZE := n
KCOV_INSTRUMENT := n