Check vfio DMA allocation size before allocating

[bonkf]

The size parameter to memory_allocate_dma() that gets passed to mmap() could be less than MIN_DMA_MEMORY, yet vfio_map_dma() always maps at least MIN_DMA_MEMORY. This is currently not an issue because MIN_DMA_MEMORY is the size of a standard 4KiB page, but it might be larger in future.

[emmericp]

@ixy-ci ping

[emmericp]

@ixy-ci ping

[ixy-ci]

pong

[emmericp]

@ixy-ci test

[ixy-ci]

Test failed!

Cause: An OpenStack error occurred: Requested operation has failed: Server 948f6c12-c333-4f69-b6be-3fe2c28c993e got into ERROR state

[emmericp]

@ixy-ci test

[ixy-ci]

Test failed!

Cause: An OpenStack error occurred: Requested operation has failed: Server 36130943-f194-49b5-a3da-a5c41dc5dceb got into ERROR state

[emmericp]

looks like the cloud is full :(

"No valid host was found. There are not enough hosts available."

[emmericp]

@ixy-ci test

[ixy-ci]

Test failed!

Cause: An OpenStack error occurred: Access to the resource is denied: Quota exceeded for instances: Requested 1, but already used 4 of 4 instances

[emmericp]

@ixy-ci test

[ixy-ci]

Test failed!

Cause: An OpenStack error occurred: Requested operation has failed: Server b7385af8-f965-4a23-8bca-f382fd76bff1 got into ERROR state

[emmericp]

cloud is still full, retried because I got this email earlier today:

In the past few weeks, we have been faced multiple times with the situation
that users were no longer able to start new VMs because of the lack of free
CPUs: the cloud was (and is!) full. To relax this situation, we have looked at
the real hardware utilization and came to the conclusion that we will overbook
the CPUs in order to be able to provide more CPUs for virtual machines than
actually exist - the compute cloud will grow virtually. Since the real CPU
load is lower than 20%, we do not expect any noticeable impact on the
performance of the VMs.

the latest test managed to spawn 2 VMs but failed on the third one, awesome

[ackxolotl]

@ixy-ci test

[ixy-ci]

Test failed!

Cause: An OpenStack error occurred: Received invalid response: openstack cli failed: Output { status: ExitStatus(ExitStatus(256)), stdout: "", stderr: "The request you have made requires authentication. (HTTP 401) (Request-ID: req-9a711922-7ff3-4d84-9ecb-434b2861af56)\n" }