** Description changed: SRU Justification Impact: The patch commit cfaa482afb97e3c05d020af80b897b061109d51f Author: Christian Brauner <[email protected]> Date: Tue Apr 14 22:26:53 2020 +0200 - UBUNTU: SAUCE: shiftfs: fix dentry revalidation + UBUNTU: SAUCE: shiftfs: fix dentry revalidation - BugLink: https://bugs.launchpad.net/bugs/1872757 + BugLink: https://bugs.launchpad.net/bugs/1872757 to fix https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1872757 regresses various btrfs + shiftfs users. Creating a btrfs subvolume, deleting it, and then trying to recreate it will cause EEXIST to be returned. It also leaves some files in a half-visible state because they are not revalidated correctly. Faulty behavior such as this can be reproduced via: btrfs subvolume create my-subvol btrfs subvolume delete my-subvol Fix: We need to revert this patch restoring the old behavior. This will briefly resurface https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1872757 which I will fix in a follow-up patch on top of this revert. We basically split the part that fixes https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1872757 out of the revert. Regression Potential: Limited to shiftfs. - Test Case: Build a kernel with fix applied and run above reproducer. + Test Case: + + sudo snap install lxd --edge + sudo snap set lxd shiftfs.enable=true + sudo systemctl restart snap.lxd.daemon + sudo lxd init --auto --storage-backend=btrfs + lxc launch images:ubuntu/focal f1 + lxc shell f1 + apt-get install btrfs-progs + findmnt | grep shiftfs # This should show that the rootfs is a shiftfs mount. + btrfs subvolume create my-subvol + btrfs subvolume delete my-subvol # Fails [1] with current updates kernel + btrfs subvolume create my-subvol + ls -al + + [1] ERROR: Could not statfs: No such file or directory
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1884767 Title: shiftfs: fix btrfs regression To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1884767/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
