** Changed in: qemu Assignee: John Snow (jnsnow) => (unassigned) -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1681439
Title: qemu-system-x86_64: hw/ide/core.c:685: ide_cancel_dma_sync: Assertion `s->bus->dma->aiocb == NULL' failed. Status in QEMU: Incomplete Bug description: Since upgrading to QEMU 2.8.0, my Windows 7 64-bit virtual machines started crashing due to the assertion quoted in the summary failing. The assertion in question was added by commit 9972354856 ("block: add BDS field to count in-flight requests"). My tests show that setting discard=unmap is needed to reproduce the issue. Speaking of reproduction, it is a bit flaky, because I have been unable to come up with specific instructions that would allow the issue to be triggered outside of my environment, but I do have a semi-sane way of testing that appears to depend on a specific initial state of data on the underlying storage volume, actions taken within the VM and waiting for about 20 minutes. Here is the shortest QEMU command line that I managed to reproduce the bug with: qemu-system-x86_64 \ -machine pc-i440fx-2.7,accel=kvm \ -m 3072 \ -drive file=/dev/lvm/qemu,format=raw,if=ide,discard=unmap \ -netdev tap,id=hostnet0,ifname=tap0,script=no,downscript=no,vhost=on \ -device virtio-net-pci,netdev=hostnet0 \ -vnc :0 The underlying storage (/dev/lvm/qemu) is a thin LVM snapshot. QEMU was compiled using: ./configure --python=/usr/bin/python2.7 --target-list=x86_64-softmmu make -j3 My virtualization environment is not really a critical one and reproduction is not that much of a hassle, so if you need me to gather further diagnostic information or test patches, I will be happy to help. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1681439/+subscriptions