Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <CGME20191206125123eucas1p1c1652484cbccef8d8df37e09affe4e25@eucas1p1.samsung.com>
 <20191206125112.11006-1-m.szyprowski@samsung.com>
In-Reply-To: <20191206125112.11006-1-m.szyprowski@samsung.com>
From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Mon, 9 Dec 2019 10:29:32 +0100
Message-ID: <CAMuHMdUsRa2QTDw4oM8SGUqfmsGt3-Mc=AnZoPV8RSqehUxyrg@mail.gmail.com>
Subject: Re: [PATCH] arm: multi_v7_config: Restore debugfs support
To:     Marek Szyprowski <m.szyprowski@samsung.com>
Cc:     linux-samsung-soc <linux-samsung-soc@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Kusanagi Kouichi <slash@ac.auone-net.jp>,
        Arnd Bergmann <arnd@arndb.de>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Olof Johansson <olof@lixom.net>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Marek,

On Fri, Dec 6, 2019 at 1:51 PM Marek Szyprowski
<m.szyprowski@samsung.com> wrote:
> Commit fd7d58f0dbc3 ("ARM: multi_v7_defconfig: renormalize based on recent
> additions") removed explicit enable line for CONFIG_DEBUG_FS, because
> that feature has been selected by other enabled options: CONFIG_TRACING,
> which were enabled by CONFIG_PERF_EVENTS.
>
> In meantime, commit 0e4a459f56c3 ("tracing: Remove unnecessary DEBUG_FS
> dependency") removed the dependency between CONFIG_DEBUG_FS and
> CONFIG_TRACING, so CONFIG_DEBUG_FS is no longer enabled in default builds.
>
> Enable it again explicitly, as debugfs support is essential for various
> automated testing tools.

... and for systemd :-(

E.g. with Debian 9 nfsroot:

    [FAILED] Failed to mount /sys/kernel/debug.
    See 'systemctl status sys-kernel-debug.mount' for details.
    [DEPEND] Dependency failed for Local File Systems.
    ...
    You are in emergGive root password for maintenance
    (or press Control-D to continue):

> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

Thank you!

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>

This is gonna bite lots of people (and defconfigs)...

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds