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: <20201118220731.925424-1-samitolvanen@google.com>
 <20201118220731.925424-16-samitolvanen@google.com> <20201123102149.ogl642tw234qod62@google.com>
In-Reply-To: <20201123102149.ogl642tw234qod62@google.com>
From:   Sami Tolvanen <samitolvanen@google.com>
Date:   Mon, 23 Nov 2020 10:34:16 -0800
Message-ID: <CABCJKudwt6xDUMADRjXU04bxZFFWOFOs_26TJGHV_vnP8Qs5Jw@mail.gmail.com>
Subject: Re: [PATCH v7 15/17] KVM: arm64: disable LTO for the nVHE directory
To:     David Brazdil <dbrazdil@google.com>
Cc:     Masahiro Yamada <masahiroy@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Will Deacon <will@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        clang-built-linux <clang-built-linux@googlegroups.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        linux-arch <linux-arch@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        linux-kbuild <linux-kbuild@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, linux-pci@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, Nov 23, 2020 at 2:21 AM David Brazdil <dbrazdil@google.com> wrote:
>
> Hey Sami,
>
> On Wed, Nov 18, 2020 at 02:07:29PM -0800, Sami Tolvanen wrote:
> > We use objcopy to manipulate ELF binaries for the nVHE code,
> > which fails with LTO as the compiler produces LLVM bitcode
> > instead. Disable LTO for this code to allow objcopy to be used.
>
> We now partially link the nVHE code (generating machine code) before objcopy,
> so I think you should be able to drop this patch now. Tried building your
> branch without it, ran a couple of unit tests and all seems fine.

Great, thanks for testing this, David! I'll drop this patch from v8.

Sami