Hello Rafael, or anyone else affected, Accepted qemu into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/qemu/1:2.5+dfsg- 5ubuntu10.7 in a few hours, and then in the -proposed repository.
Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users. If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision. Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance! ** Changed in: qemu (Ubuntu Xenial) Status: In Progress => Fix Committed ** Tags added: verification-needed -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1626972 Title: QEMU memfd_create fallback mechanism change for security drivers Status in Ubuntu Cloud Archive: In Progress Status in QEMU: In Progress Status in qemu package in Ubuntu: Fix Released Status in qemu source package in Xenial: Fix Committed Status in qemu source package in Yakkety: In Progress Status in qemu source package in Zesty: Fix Released Bug description: [Impact] * Updated QEMU (from UCA) live migration doesn't work with 3.13 kernels. * QEMU code checks if it can create /tmp/memfd-XXX files wrongly. * Apparmor will block access to /tmp/ and QEMU will fail migrating. [Test Case] * Install 2 Ubuntu Trusty (3.13) + UCA Mitaka + apparmor rules. * Try to live-migration from one to another. * Apparmor will block creation of /tmp/memfd-XXX files. [Regression Potential] Pros: * Exhaustively tested this. * Worked with upstream on this fix. * I'm implementing new vhost log mechanism for upstream. * One line change to a blocker that is already broken. Cons: * To break live migration in other circumstances. [Other Info] * Christian Ehrhardt has been following this. ORIGINAL DESCRIPTION: When libvirt starts using apparmor, and creating apparmor profiles for every virtual machine created in the compute nodes, mitaka qemu (2.5 - and upstream also) uses a fallback mechanism for creating shared memory for live-migrations. This fall back mechanism, on kernels 3.13 - that don't have memfd_create() system-call, try to create files on /tmp/ directory and fails.. causing live-migration not to work. Trusty with kernel 3.13 + Mitaka with qemu 2.5 + apparmor capability = can't live migrate. From qemu 2.5, logic is on : void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals, int *fd) { if (memfd_create)... ### only works with HWE kernels else ### 3.13 kernels, gets blocked by apparmor tmpdir = g_get_tmp_dir ... mfd = mkstemp(fname) } And you can see the errors: From the host trying to send the virtual machine: 2016-08-15 16:36:26.160 1974 ERROR nova.virt.libvirt.driver [req-0cac612b-8d53-4610-b773-d07ad6bacb91 691a581cfa7046278380ce82b1c38ddd 133ebc3585c041aebaead8c062cd6511 - - -] [instance: 2afa1131-bc8c-43d2-9c4a-962c1bf7723e] Migration operation has aborted 2016-08-15 16:36:26.248 1974 ERROR nova.virt.libvirt.driver [req-0cac612b-8d53-4610-b773-d07ad6bacb91 691a581cfa7046278380ce82b1c38ddd 133ebc3585c041aebaead8c062cd6511 - - -] [instance: 2afa1131-bc8c-43d2-9c4a-962c1bf7723e] Live Migration failure: internal error: unable to execute QEMU command 'migrate': Migration disabled: failed to allocate shared memory From the host trying to receive the virtual machine: Aug 15 16:36:19 tkcompute01 kernel: [ 1194.356794] type=1400 audit(1471289779.791:72): apparmor="STATUS" operation="profile_load" profile="unconfined" name="libvirt-2afa1131-bc8c-43d2-9c4a-962c1bf7723e" pid=12565 comm="apparmor_parser" Aug 15 16:36:19 tkcompute01 kernel: [ 1194.357048] type=1400 audit(1471289779.791:73): apparmor="STATUS" operation="profile_load" profile="unconfined" name="qemu_bridge_helper" pid=12565 comm="apparmor_parser" Aug 15 16:36:20 tkcompute01 kernel: [ 1194.877027] type=1400 audit(1471289780.311:74): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="libvirt-2afa1131-bc8c-43d2-9c4a-962c1bf7723e" pid=12613 comm="apparmor_parser" Aug 15 16:36:20 tkcompute01 kernel: [ 1194.904407] type=1400 audit(1471289780.343:75): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="qemu_bridge_helper" pid=12613 comm="apparmor_parser" Aug 15 16:36:20 tkcompute01 kernel: [ 1194.973064] type=1400 audit(1471289780.407:76): apparmor="DENIED" operation="mknod" profile="libvirt-2afa1131-bc8c-43d2-9c4a-962c1bf7723e" name="/tmp/memfd-tNpKSj" pid=12625 comm="qemu-system-x86" requested_mask="c" denied_mask="c" fsuid=107 ouid=107 Aug 15 16:36:20 tkcompute01 kernel: [ 1194.979871] type=1400 audit(1471289780.411:77): apparmor="DENIED" operation="open" profile="libvirt-2afa1131-bc8c-43d2-9c4a-962c1bf7723e" name="/tmp/" pid=12625 comm="qemu-system-x86" requested_mask="r" denied_mask="r" fsuid=107 ouid=0 Aug 15 16:36:20 tkcompute01 kernel: [ 1194.979881] type=1400 audit(1471289780.411:78): apparmor="DENIED" operation="open" profile="libvirt-2afa1131-bc8c-43d2-9c4a-962c1bf7723e" name="/var/tmp/" pid=12625 comm="qemu-system-x86" requested_mask="r" denied_mask="r" fsuid=107 ouid=0 When leaving libvirt without apparmor capabilities (thus not confining virtual machines on compute nodes, the live migration works as expected, so, clearly, apparmor is stepping into the live migration). I'm sure that virtual machines have to be confined and that this isn't the desired behaviour... To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-archive/+bug/1626972/+subscriptions