| 2bd3bce8 | 05-Jun-2014 |
Paolo Bonzini <pbonzini@redhat.com> |
block: asynchronously stop the VM on I/O errors
With virtio-blk dataplane, I/O errors might occur while QEMU is
not in the main I/O thread. However, it's invalid to call vm_stop
when we're neither
block: asynchronously stop the VM on I/O errors
With virtio-blk dataplane, I/O errors might occur while QEMU is
not in the main I/O thread. However, it's invalid to call vm_stop
when we're neither in a VCPU thread nor in the main I/O thread,
even if we were to take the iothread mutex around it.
To avoid this problem, we can raise a request to the main I/O thread,
similar to what QEMU does when vm_stop is called from a CPU thread.
We know that bdrv_error_action is called from an AIO callback, and
the moment at which the callback will fire is not well-defined; it
depends on the moment at which the disk or OS finishes the operation,
which can happen at any time. Note that QEMU is certainly not in a CPU
thread and we do not need to call cpu_stop_current() like vm_stop() does.
However, we need to ensure that any action taken by management will
result in correct detection of the error _and_ a running VM. In particular:
- the event must be raised after the iostatus has been set, so that
"info block" will return an iostatus that matches the event.
- the VM must be stopped after the iostatus has been set, so that
"info block" will return an iostatus that matches the runstate.
The ordering between the STOP and BLOCK_IO_ERROR events is preserved;
BLOCK_IO_ERROR is documented to come first.
This makes bdrv_error_action() thread safe (assuming QMP events are,
which is attacked by a separate series).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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| a77e6b14 | 10-Jun-2014 |
Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> |
Add qtest for vhost-user
This test creates a 'server' chardev to listen for vhost-user messages.
Once VHOST_USER_SET_MEM_TABLE is received it mmaps each received region,
and read 1k bytes from it. T
Add qtest for vhost-user
This test creates a 'server' chardev to listen for vhost-user messages.
Once VHOST_USER_SET_MEM_TABLE is received it mmaps each received region,
and read 1k bytes from it. The read data is compared to data from readl.
The test requires hugetlbfs to be already mounted and writable. The mount
point defaults to '/hugetlbfs' and can be specified via the environment
variable QTEST_HUGETLBFS_PATH.
The rom pc-bios/pxe-virtio.rom is used to instantiate a virtio pcicontroller.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
MST: fix up coding style
MST: disable vhost test temporarily
This test needs a bit more work: issues have been
found on legacy systems, disable it for now to
avoid false positives for people.
Will re-enable after issues are addressed.
Reported-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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