Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <34ca6034-331c-7c6c-ddd4-f774dc8f22ce@kernel.org>
Date:   Tue, 15 Nov 2022 07:36:08 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.4.1
Subject: Re: [PATCH 02/46] kbuild: pass jobserver to cmd_ld_vmlinux.o
Content-Language: en-US
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     linux-kernel@vger.kernel.org, Jiri Slaby <jslaby@suse.cz>,
        Sedat Dilek <sedat.dilek@gmail.com>,
        Michal Marek <michal.lkml@markovi.net>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Martin Liska <mliska@suse.cz>
References: <20221114114344.18650-1-jirislaby@kernel.org>
 <20221114114344.18650-3-jirislaby@kernel.org>
 <CAK7LNASUb0PLiZahw46c0qBUn_caMWm2SrtY1Hb8Vd7RzsAwzg@mail.gmail.com>
From:   Jiri Slaby <jirislaby@kernel.org>
In-Reply-To: <CAK7LNASUb0PLiZahw46c0qBUn_caMWm2SrtY1Hb8Vd7RzsAwzg@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 14. 11. 22, 18:57, Masahiro Yamada wrote:
> On Mon, Nov 14, 2022 at 8:44 PM Jiri Slaby (SUSE) <jirislaby@kernel.org> wrote:
>>
>> From: Jiri Slaby <jslaby@suse.cz>
>>
>> Until the link-vmlinux.sh split (cf. the commit below), the linker was
>> run with jobserver set in MAKEFLAGS. After the split, the command in
>> Makefile.vmlinux_o is not prefixed by "+" anymore, so this information
>> is lost.
>>
>> Restore it as linkers working in parallel (namely gcc LTO) make a use of
>> it. Actually, they complain, if jobserver is not set:
>>    lto-wrapper: warning: jobserver is not available: '--jobserver-auth=' is not present in 'MAKEFLAGS'
>>
>> Fixes: 5d45950dfbb1 (kbuild: move vmlinux.o link to scripts/Makefile.vmlinux_o)
> 
> 
> This Fixes is wrong since GCC LTO is not in upstream code.

Yup, this is a left-over. Now dropped from both.

thanks,
-- 
js