Red Hat Bugzilla – Bug 224587
Make sure PV-on-HVM xen has an entropy source
Last modified: 2018-10-19 17:14:38 EDT
Description of problem:
When using PV-on-HVM drivers with Xen, there is no interrupt source to provide
data to the entropy pool used by /dev/random and /dev/urandom. This leads to
PV-on-HVM guests blocking on attempts to read /dev/random (urandom will fall
back to a pseudo-RNG and not block).
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Create a HVM guest configured to use vbd for the system disk
2. Read from /dev/random, for e.g.:
The reading process will block for ever waiting for the entropy pool to be refilled.
The reading process makes progress as interrupts replenish the data in the
PV-on-HVM is not supported in RHEL5 GA and no PV-on-HVM drivers are shipped.
This bug targets future releases which may contain this support.
Created attachment 146686 [details]
make platform_pci interrupts use SA_SAMPLE_RANDOM
This patch was created by Fujitsu's engineers and submitted to upstream xen:
The patch was merged in xen-unstable in the following commit:
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release. Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products. This request is not yet committed for inclusion in an Update
Review & test in 5.1 beta.
change QA contact
xen-3.1 upstream (which the upcoming pv-on-hvm packages are based on) has the