What kind of logfiles do you require? Just install separate /home on btrfs, start watching some porn in browser or some other activity activity writing to files in there and force shutdown your desktop by long-press of power button. Do this several times until the fs is corrupted (you'll notice it due to stuck boot) and try to use recovery mode and liveusb.
** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1452165 Title: currupted btrfs breaks both recovery and boot Status in linux package in Ubuntu: Confirmed Bug description: If btrfs volume is corrupted (separate /home partition, not even / !!!) than not only booting ubuntu in normal AND recovery mode is impossible but even liveusb fails as well. The recovery drops to shell but it's impossible to fix btrfs - there's unkillable mount -t btrfs... process hanging and kernel regularly pukes with "btrfs- transacti blocked for 120 seconds" message. This is beyond horrible - the whole purpose of recovery mode is to fix errors like that, errors on partition which is not used to boot from (e. g. /home) should never ever break it. Alternatively you could add new mode to grub menu - smth like "recovery which actually works" or something like that. The workaround is to add 'break=premount' to grub command line and fix btrfs with 'btrfs check --repair /dev/dm-....' from initramfs. Found on xubuntu 15.04 x86_64. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1452165/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp