Public bug reported: [impact] 4.4.0-101+ (also 4.4.0-109) Ubuntu kernels no longer can use qemu-nbd to mount virtual disks onto a local filesystem (see test case for reproducer). 4.4.0-98 works without issue.
I was able to bisect the issue down to 907196aba0d891c6d580abe69c36d3b4fd512dcc (a cherry-pick from 37091fdd831f28a6509008542174ed324dd645bc). Reverting this from 4.4 fixes the issue. Installing the mainline kernel shows mainline is _not_ affected by this bug. In addition this is also reported in debian here: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=829532 [test case] # given a vmdk disk with multiple partitions sudo modprobe nbd sudo qemu-nbd -d /dev/nbd0 sudo qemu-nbd -r -c /dev/nbd0 disk.vmdk ls /dev/nbd0* # here you won't see multiple partition, nor be able to mount a partition locally ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Affects: linux (Ubuntu Xenial) Importance: Undecided Status: New ** Also affects: linux (Ubuntu Xenial) Importance: Undecided Status: New ** Description changed: [impact] 4.4.0-101+ (also 4.4.0-109) Ubuntu kernels no longer can use qemu-nbd to mount virtual disks onto a local filesystem (see test case for reproducer). I was able to bisect the issue down to - 907196aba0d891c6d580abe69c36d3b4fd512dcc. Reverting this from 4.4 fixes + 907196aba0d891c6d580abe69c36d3b4fd512dcc (a cherry-pick from + 37091fdd831f28a6509008542174ed324dd645bc). Reverting this from 4.4 fixes the issue. In addition this is also reported in debian here: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=829532 [test case] # given a vmdk disk with multiple partitions sudo modprobe nbd sudo qemu-nbd -d /dev/nbd0 sudo qemu-nbd -r -c /dev/nbd0 disk.vmdk ls /dev/nbd0* # here you won't see multiple partition, nor be able to mount a partition locally ** Description changed: [impact] - 4.4.0-101+ (also 4.4.0-109) Ubuntu kernels no longer can use qemu-nbd to mount virtual disks onto a local filesystem (see test case for reproducer). + 4.4.0-101+ (also 4.4.0-109) Ubuntu kernels no longer can use qemu-nbd to mount virtual disks onto a local filesystem (see test case for reproducer). 4.4.0-98 works without issue. I was able to bisect the issue down to 907196aba0d891c6d580abe69c36d3b4fd512dcc (a cherry-pick from 37091fdd831f28a6509008542174ed324dd645bc). Reverting this from 4.4 fixes the issue. + + Installing the mainline kernel shows mainline is _not_ affected by this + bug. In addition this is also reported in debian here: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=829532 [test case] # given a vmdk disk with multiple partitions sudo modprobe nbd sudo qemu-nbd -d /dev/nbd0 sudo qemu-nbd -r -c /dev/nbd0 disk.vmdk ls /dev/nbd0* # here you won't see multiple partition, nor be able to mount a partition locally -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1743026 Title: qemu-nbd -c /dev/nbd0 fails to map partitions To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1743026/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs