Re: kasan patches

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Aug 13, 2018 at 02:25:12PM -0700, Nick Desaulniers wrote:
> On Sat, Aug 11, 2018 at 9:40 AM Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > On Mon, Aug 06, 2018 at 02:08:32PM -0700, Nick Desaulniers wrote:
> > > These patches are needed for kasan+clang support.  I confirmed they
> > > apply cleanly in order (top to bottom):
> > >
> > > 4.9:
> > > commit c5caf21ab0cf8 ("kasan: turn on -fsanitize-address-use-after-scope")
> > > commit 0e410e158e5b ("kasan: don't emit builtin calls when sanitization is off")
> >
> > By applying these, I get a ton of new build warnings, so I can't add
> > them :(
> 
> What? Such innocent patches.
> 
> $ git remote add stable
> git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
> $ git checkout -b 4.9-stable-kasan stable/linux-4.9.y
> <git log shows 4.9.118>
> $ git cherry-pick c5caf21ab0cf8
> $ git cherry-pick 0e410e158e5b
> $ make defconfig
> $ make -j46
> 
> I get -Wstringop-truncation, -Wstringop-overflow=,
> -Wpacked-not-aligned, -Warray-bounds warnings with gcc-8 with or
> without these patches.
> 
> Can you share your config, or what the warning was?  Did I checkout
> the wrong branch?

I used 'make allmodconfig' on a x86 Fedora 27 release which is using gcc
7.3.1.  Adding those patches adds a ton of warnings.  Let me go do a
test build and send you the full log...

thanks,

greg k-h