I tried an upstream kernel (4.4.48-040448-generic #201702090334). This is still doing the same thing.
I have seen the messages below logged relating to the DVD drive when lshw is run. If I remove the DVD drive from the VM hardware the issue goes away. Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044077] sr 0:0:0:1: [sr0] tag#2 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044082] sr 0:0:0:1: [sr0] tag#2 Sense Key : Not Ready [current] Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044085] sr 0:0:0:1: [sr0] tag#2 Add. Sense: Medium not present - tray closed Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044088] sr 0:0:0:1: [sr0] tag#2 CDB: Read(10) 28 00 00 00 00 00 00 00 08 00 Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044090] blk_update_request: critical target error, dev sr0, sector 0 Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044158] sr 0:0:0:1: [sr0] unaligned transfer Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044162] sr 0:0:0:1: [sr0] unaligned transfer Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044165] sr 0:0:0:1: [sr0] unaligned transfer Feb 16 11:59:10 ubuntu16-test kernel: [ 88.044168] sr 0:0:0:1: [sr0] unaligned transfer These "unaligned transfer" messages repeat about 100 times. All messages have an identical time though the symptoms of the high cpu wait % last about a minute. This does not occur in a 16.04 VM on VMware with a DVD drive, so the issue seems to be how the DVD drive is handled on the 4.4 kernel in a Hyper-V VM. Is there a workaround to make it skip the DVD drive if empty? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1663263 Title: lshw run on Hyper-V VM hangs system To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1663263/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
