(Yes, I use grub2.) Actually, grub-mkconfig is just a bunch of scripts, I should be able to grep and cut fstab and generate rootflags from that, shouldn't I? :) Is the cmdline size still limited to 255 characters? On 20 January 2016 at 21:48, Garmine 42 <mikro001@xxxxxxxxx> wrote: > I would like to avoid modifying rootflags inside grub config so if I > change anything in fstab I don't have to change that in other places > as well. Unless grub-mkconfig can somehow be taught to parse fstab and > set the rootflags according to it. > > On 20 January 2016 at 21:43, Devon Smith <devo8604@xxxxxxxxx> wrote: >> Garmine, >> If you are using grub2 you should be able to add that option in >> your grub config, then regenerate it, that will make that option >> permanent and you wont have to add it every time at boot. Also, if >> 'ro' is in your kernel params at boot, then im pretty sure masking the >> remount service will ensure that your root remains mounted ro... >> >> Devon >> >> On Wed, Jan 20, 2016 at 1:34 PM, Garmine 42 <mikro001@xxxxxxxxx> wrote: >>> On 20 January 2016 at 21:18, Leonid Isaev >>> <leonid.isaev@xxxxxxxxxxxxxxxxx> wrote: >>>> On Wed, Jan 20, 2016 at 09:01:22PM +0100, Garmine 42 wrote: >>>>> There was a discussion on the linux-btrfs mailing list about this, and >>>>> for example the btrfs space_cache option can not be changed with a >>>>> remount - this causes the fstab file's space_cache option to be >>>>> basically ignored. I want to eliminate this kind of issue on my setup, >>>>> that's why I need to avoid root being remounted. Instead I want root >>>>> to be mounted with the options specified in fstab the first (and only) >>>>> time. >>>> >>>> Why is it ignored? >>>> /dev/sda4 on / type btrfs (ro,nodev,relatime,compress=zlib,ssd,space_cache,autodefrag,subvolid=257,subvol=/_root) >>>> ^^^^^^^^^^^ >>> >>> The linux-btrfs discussion suggests that some mount options might be >>> unchanged after a remount even if it should change based on the fstab. >>> >>> Although that particular discussion's exact problem was something else >>> in my opinion, so they might be wrong on that. The fix for that >>> problem was including the problematic option (space_cache=v2) in the >>> rootflags parameter. Considering the cmdline size is limited and I >>> want to avoid modifying that all the time, I want to mount the root >>> volume with the correct flags in the first place. >>> >>>> Also, there is fstab in the initramfs: >>>> $ lsinitcpio /boot/initramfs-linux.img | grep fstab >>>> etc/fstab >>> >>> That fstab is an empty file (ran in an uncompreseed initrd): >>> % wc -c etc/fstab >>> 0 etc/fstab >>> >>>> Have you tried masking the systemd-remount-fs.service? >>> >>> First I will try to exclude root= and rootflags= parameters from the >>> cmdline and include the fstab via mkinitcpio and see if it finds the >>> root. Do I want to mask remount-fs in this case? >>> >>>> Cheers, >>>> -- >>>> Leonid Isaev >>>> GPG fingerprints: DA92 034D B4A8 EC51 7EA6 20DF 9291 EE8A 043C B8C4 >>>> C0DF 20D0 C075 C3F1 E1BE 775A A7AE F6CB 164B 5A6D
