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Sat, 17 Sep 2022 13:05:39 -0700 (PDT) Message-ID: <5762dfb5-832f-a075-3be9-7d32cb82b661@mind.be> Date: Sat, 17 Sep 2022 22:05:37 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.2.1 Content-Language: en-GB To: Zvi Vered , buildroot@buildroot.org References: From: Arnout Vandecappelle In-Reply-To: X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mind.be; s=google; h=content-transfer-encoding:in-reply-to:from:references:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date; bh=Cf9Fu2hqFkq7qyJD/tpPTcrRF/ZMzpjWCgtRF9ODYiU=; b=h46jmwiFh8pZSTIE7DC5DJT0mn1Bm6A+blQ1U8XznovhL8XZt21UkU0Lq82IA66Ssy QgzyAUvIflCAgXVmRUkijLedB+LaZ6ZTTf/3fz0Lfo/ruDPD1fZoH14xe1b7mTgu9Qr2 xgODh4byLKRpve1zq2A90EanNzdDso5DfVSr8BD2khoDBGhDQ06Jxv6aDCpcZtdWk3qJ uBisZQzYRy+ct5KvB5uxZHhWgad9iQWSE1LYgruANv+3oSCRumfdYFcv0Ioh0YY5zHDk EeOqUvHhW8Juz3LKImaG9FtA+DoZnru9vuQShp/dNwdnjscQ6zhBS77IUIkjV2tFBtNm DwSQ== X-Mailman-Original-Authentication-Results: smtp2.osuosl.org; dkim=pass (2048-bit key) header.d=mind.be header.i=@mind.be header.a=rsa-sha256 header.s=google header.b=h46jmwiF Subject: Re: [Buildroot] 2022.02.1: read-only file system X-BeenThere: buildroot@buildroot.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion and development of buildroot List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: buildroot-bounces@buildroot.org Sender: "buildroot" On 11/09/2022 19:58, Zvi Vered wrote: > Hello, > > I'm using buildroot 2022.02.1 under x86 embedded SBC. > The root file system is located on the on-board disk. > The boot argument contains 'ro' (checked with /proc/cmdline after login) but the > disk is not read-only. There is a buildroot config option BR2_TARGET_GENERIC_REMOUNT_ROOTFS_RW which defaults to enabled. It will remount the rootfs to read-write as part of processing /etc/fstab. So you should probably turn that option off. Note that if you use systemd, you'll need to do a clean rebuild before the option is taken into account. > When I used the same boot args with busybox, it worked fine. > Of course with busybox I had to tailor all other mandatory files and directories. > > I need read-only rootfs to defend this embedded system in case of power-down / > cold reset. Perhaps you're better off then to use an actual readonly filesystem, like erofs or squashfs? You have to make sure the corresponding kernel options are enabled, of course. Regards, Arnout > > Beyond the default configuration, the rootfs also contains ntp client, httpd, > pci tools. > > Thank you, > Zvika > > > > _______________________________________________ > buildroot mailing list > buildroot@buildroot.org > https://lists.buildroot.org/mailman/listinfo/buildroot _______________________________________________ buildroot mailing list buildroot@buildroot.org https://lists.buildroot.org/mailman/listinfo/buildroot