Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210922205525.570068-1-nathan@kernel.org> <CA+fCnZdfMYvQ1o8n41dDzgJUArsUyhnb9Y_azgCVuzj6_KBifA@mail.gmail.com>
 <YV0NPnUbElw7cTRH@archlinux-ax161>
In-Reply-To: <YV0NPnUbElw7cTRH@archlinux-ax161>
From:   Andrey Konovalov <andreyknvl@gmail.com>
Date:   Wed, 6 Oct 2021 13:57:28 +0200
Message-ID: <CA+fCnZc5=fqM=eEZ3RLqBFaxR72bjxndDdnM_rOkiSBi3+2L6A@mail.gmail.com>
Subject: Re: [PATCH] kasan: Always respect CONFIG_KASAN_STACK
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        Marco Elver <elver@google.com>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Arnd Bergmann <arnd@arndb.de>,
        kasan-dev <kasan-dev@googlegroups.com>,
        LKML <linux-kernel@vger.kernel.org>, llvm@lists.linux.dev
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, Oct 6, 2021 at 4:43 AM Nathan Chancellor <nathan@kernel.org> wrote:
>
> > This part of code always looked weird to me.
> >
> > Shouldn't we be able to pull all these options out of the else section?
> >
> > Then, the code structure would make sense: first, try applying
> > KASAN_SHADOW_OFFSET; if failed, use CFLAGS_KASAN_MINIMAL; and then try
> > applying all these options one by one.
>
> Prior to commit 1a69e7ce8391 ("kasan/Makefile: support LLVM style asan
> parameters"), all the flags were run under one cc-option, meaning that
> if $(KASAN_SHADOW_OFFSET) was not set, the whole call would fail.
> However, after that commit, it is possible to do this but I was not sure
> if that was intentional so I went for the minimal fix.

Ack. Filed https://bugzilla.kernel.org/show_bug.cgi?id=214629 for the rest.

Thanks!