vm/guest: Drop obsoleted entropy-related daemons#68
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khwrngd provides the same functionality as rngd here, but is integrated in the
kernel, and started by default by the hwrng driver as soon as the device is
initialized.
It was added in Linux 3.17 by the following commit:
commit be4000bc4644d027c519b6361f5ae3bbfc52c347
Author: Torsten Duwe <duwe@lst.de>
Date: Sat Jun 14 23:46:03 2014 -0400
hwrng: create filler thread
This can be viewed as the in-kernel equivalent of hwrngd;
like FUSE it is a good thing to have a mechanism in user land,
but for some reasons (simplicity, secrecy, integrity, speed)
it may be better to have it in kernel space.
This patch creates a thread once a hwrng registers, and uses
the previously established add_hwgenerator_randomness() to feed
its data to the input pool as long as needed. A derating factor
is used to bias the entropy estimation and to disable this
mechanism entirely when set to zero.
There are no benefits to having it on the guest, since we use virtio-rng to provide entropy from the host. vm_guest_force_haveged is added to support overriding that, in the special case of vex (which doesn't seem to use virtio-rng, probably because its kernel is too ancient)
nicoonoclaste
changed the title
Doing otherwise would conflict with vm/guest. Installing it only in vm/host is insufficient: we have physical machines that aren't used as hypervisors, such as wuerfel.
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vm/guest: uninstallrngd: unnecessary for virtio-rng since kernel 3.17, which introduced khwrngd:a kernel thread which provides the same functionality, but is integrated in the kernel, and started by default by the hwrng driver as soon as the device is initialized.
havegedunnecessary on virtual machines, which get their entropy form the host via virtio-rng:vm/guestuninstallhaveged;baseandvm/hostinstallhavegedon physical machines;added a fix to
vm/guestso it could be tested in check mode.