Reviewed: https://review.opendev.org/708030 Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=dbb58e964ad1821e96f3e6758b3add747339d052 Submitter: Zuul Branch: master
commit dbb58e964ad1821e96f3e6758b3add747339d052 Author: Lee Yarwood <[email protected]> Date: Sat Feb 15 11:33:48 2020 +0000 workarounds: Add option to disable native LUKSv1 decryption by QEMU Recently discovered performance issues with the libgcrypt library [1] mean that operators may wish to avoid the now default native decryption of LUKSv1 volumes as of I5a0de814f2868f1a4980a69b72b45ee829cedb94. This change introduces a ``[workarounds]/disable_native_luksv1`` option to disable this native decryption by QEMU, allowing Nova to fallback to the dm-crypt based os-brick encryptors. This workaround is temporary and will be removed during the W release once all impacted distributions have been able to update their versions of the libgcrypt library. The _is_luks_v1 method previously used to confirm if a LUKSv1 encryption provider is being used has been renamed _allow_native_luksv1 and repurposed to determine if native LUKSv1 decryption by QEMU is allowed. [1] https://bugzilla.redhat.com/show_bug.cgi?id=1762765 Closes-Bug: #1869182 Change-Id: Ia500eb614cf575ab846f64f4b69c9068274c8c1f ** Changed in: nova Status: In Progress => Fix Released ** Bug watch added: Red Hat Bugzilla #1762765 https://bugzilla.redhat.com/show_bug.cgi?id=1762765 -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to OpenStack Compute (nova). https://bugs.launchpad.net/bugs/1869182 Title: Poor LUKSv1 performance when using native QEMU decryption Status in OpenStack Compute (nova): Fix Released Bug description: Description =========== LUKSv1 encrypted volumes have been natively decrypted by QEMU since I5a0de814f2868f1a4980a69b72b45ee829cedb94. This behaviour is not optional at present. Recently discovered performance issues within the libgcrypt library [1] used by QEMU to decrypt LUKSv1 disks mean that some users may wish to disable this feature within the libvirt driver. Disabling native decryption by QEMU should result in the original dm- crypt approach being taken using encryptors provided from os-brick. [1] https://bugzilla.redhat.com/show_bug.cgi?id=1762765 Steps to reproduce ================== * Attach a LUKSv1 encrypted volume to an instance * Test I/O performance within the instance to the volume. Expected result =============== Performance is close to baremetal performance using dm-crypt. Actual result ============= Performance is severely degraded if the libgcrypt issue [1] is not resolved on the host. Environment =========== 1. Exact version of OpenStack you are running. See the following list for all releases: http://docs.openstack.org/releases/ Master. 2. Which hypervisor did you use? (For example: Libvirt + KVM, Libvirt + XEN, Hyper-V, PowerKVM, ...) What's the version of that? libvirt + QEMU/KVM 2. Which storage type did you use? (For example: Ceph, LVM, GPFS, ...) What's the version of that? N/A - LUKSv1 encryption used. 3. Which networking type did you use? (For example: nova-network, Neutron with OpenVSwitch, ...) N/A Logs & Configs ============== N/A To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1869182/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
