Comment 129 for bug 1470250

It looks like there is a race condition and the corruption occurs when the FREEZE happens to late. No wonder as it's happening from userland.

Mar 16 15:06:49 emsi-02 kernel: [422953.038989] sd 2:0:0:0: [storvsc] Sense Key : Unit Attention [current]
Mar 16 15:06:49 emsi-02 kernel: [422953.039003] sd 2:0:0:0: [storvsc] Add. Sense: Changed operating definition
Mar 16 15:06:49 emsi-02 kernel: [422953.039058] sd 2:0:0:0: Warning! Received an indication that the operating parameters on this target have changed. The Linux SCSI layer does not automatically adjust these parameters.
Mar 16 15:06:49 emsi-02 kernel: [422953.039063] blk_update_request: I/O error, dev sda, sector 0
Mar 16 15:06:49 emsi-02 Hyper-V VSS: VSS: op=FREEZE: succeeded
Mar 16 15:06:49 emsi-02 kernel: [422953.072223] sd 2:0:0:0: [storvsc] Sense Key : Unit Attention [current]
Mar 16 15:06:49 emsi-02 kernel: [422953.072235] sd 2:0:0:0: [storvsc] Add. Sense: Changed operating definition
Mar 16 15:06:49 emsi-02 kernel: [422953.072242] sd 2:0:0:0: Warning! Received an indication that the operating parameters on this target have changed. The Linux SCSI layer does not automatically adjust these parameters.
Mar 16 15:06:49 emsi-02 Hyper-V VSS: VSS: op=THAW: succeeded