xenial 4.4.0-49.70 kernel breaks LXD userspace

The verification of the Stable Release Update for linux-lts-xenial has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

This bug was fixed in the package linux - 4.4.0-51.72

---------------
linux (4.4.0-51.72) xenial; urgency=low

  [ Luis Henriques ]

  * Release Tracking Bug
    - LP: #1644611

  * 4.4.0-1037-snapdragon #41: kernel panic on boot (LP: #1644596)
    - Revert "dma-mapping: introduce the DMA_ATTR_NO_WARN attribute"
    - Revert "powerpc: implement the DMA_ATTR_NO_WARN attribute"
    - Revert "nvme: use the DMA_ATTR_NO_WARN attribute"

linux (4.4.0-50.71) xenial; urgency=low

  [ Luis Henriques ]

  * Release Tracking Bug
    - LP: #1644169

  * xenial 4.4.0-49.70 kernel breaks LXD userspace (LP: #1644165)
    - Revert "UBUNTU: SAUCE: (namespace) fuse: Allow user namespace mounts by
      default"
    - Revert "UBUNTU: SAUCE: (namespace) fs: Don't remove suid for CAP_FSETID for
      userns root"
    - Revert "(namespace) Revert "UBUNTU: SAUCE: fs: Don't remove suid for
      CAP_FSETID in s_user_ns""
    - Revert "UBUNTU: SAUCE: (namespace) fs: Allow superblock owner to change
      ownership of inodes"
    - Revert "(namespace) Revert "UBUNTU: SAUCE: fs: Allow superblock owner to
      change ownership of inodes with unmappable ids""
    - Revert "UBUNTU: SAUCE: (namespace) security/integrity: Harden against
      malformed xattrs"
    - Revert "(namespace) Revert "UBUNTU: SAUCE: ima/evm: Allow root in s_user_ns
      to set xattrs""
    - Revert "(namespace) dquot: For now explicitly don't support filesystems
      outside of init_user_ns"
    - Revert "(namespace) quota: Handle quota data stored in s_user_ns in
      quota_setxquota"
    - Revert "(namespace) quota: Ensure qids map to the filesystem"
    - Revert "(namespace) Revert "UBUNTU: SAUCE: quota: Convert ids relative to
      s_user_ns""
    - Revert "(namespace) Revert "UBUNTU: SAUCE: quota: Require that qids passed
      to dqget() be valid and map into s_user_ns""
    - Revert "(namespace) vfs: Don't create inodes with a uid or gid unknown to
      the vfs"
    - Revert "(namespace) vfs: Don't modify inodes with a uid or gid unknown to
      the vfs"
    - Revert "UBUNTU: SAUCE: (namespace) fuse: Translate ids in posix acl xattrs"
    - Revert "UBUNTU: SAUCE: (namespace) posix_acl: Export
      posix_acl_fix_xattr_userns() to modules"
    - Revert "(namespace) vfs: Verify acls are valid within superblock's
      s_user_ns."
    - Revert "(namespace) Revert "UBUNTU: SAUCE: fs: Update posix_acl support to
      handle user namespace mounts""
    - Revert "(namespace) fs: Refuse uid/gid changes which don't map into
      s_user_ns"
    - Revert "(namespace) Revert "UBUNTU: SAUCE: fs: Refuse uid/gid changes which
      don't map into s_user_ns""
    - Revert "(namespace) mnt: Move the FS_USERNS_MOUNT check into sget_userns"

linux (4.4.0-49.70) xenial; urgency=low

  [ Luis Henriques ]

  * Release Tracking Bug
    - LP: #1640921

  * Infiniband driver (kernel module) needed for Azure (LP: #1641139)
    - SAUCE: RDMA Infiniband for Windows Azure
    - [Config] CONFIG_HYPERV_INFINIBAND_ND=m
    - SAUCE: Makefile RDMA infiniband driver for Windows Azure
    - [Config] Add hv_network_direct.ko to generic inclusion list
    - SAUCE: RDMA Infiniband for Windows Azure is dependent on amd64...