On Mon, 13 Jun 2011, Venkatesh Pallipadi wrote:
On Mon, Jun 13, 2011 at 3:06 PM, Jarod Wilson ja...@redhat.com wrote:
TSC is high enough resolution that we can use its low-order byte to
stir new data into the random number generator entropy pool.
From what I vaguely remember from years
H. Peter Anvin wrote:
Those already are doing this.
They used to via IRQF_SAMPLE_RANDOM, but these are being removed
(according to Documentation/feature-removal-schedule.txt). In 2.6.39 I
can only find 10 remaining instances, out of many more network drivers.
The alternative is supposed to
H. Peter Anvin wrote:
On 06/13/2011 05:39 PM, Kent Borg wrote:
I was assuming that drivers, responding to an interrupt from some
external event, would want to make this call.
Such as a network driver.
Those already are doing this.
Two points:
1. Why look at the high-order bits? How are
On Tue, 2011-06-14 at 08:39 -0400, Kent Borg wrote:
H. Peter Anvin wrote:
Those already are doing this.
They used to via IRQF_SAMPLE_RANDOM, but these are being removed
(according to Documentation/feature-removal-schedule.txt). In 2.6.39 I
can only find 10 remaining instances, out of
Matt Mackall wrote:
Kent Borg wrote:
So network entropy is being eradicated, and nothing is being done to
replace it.
Nothing is being done is a more accurate summary of the situation.
So the feature-removal-schedule.txt entry about IRQF_SAMPLE_RANDOM is
obsolete?
(Then the trend from
On Tue, 2011-06-14 at 13:48 -0400, Kent Borg wrote:
Matt Mackall wrote:
Kent Borg wrote:
So network entropy is being eradicated, and nothing is being done to
replace it.
Nothing is being done is a more accurate summary of the situation.
So the feature-removal-schedule.txt entry
On 06/13/2011 04:10 PM, Matt Mackall wrote:
Well the issue is that samples are going to be roughly aligned to some
multiple of the bus frequency. If an interrupt occurs on bus cycle X,
this code will be hit at roughly TSC cycle X*M+d.
This is correct; at the very least I would multiply the
Matt Mackall wrote:
[network adapters are] a great source of potential entropy, a bad
source of guaranteed entropy. The current RNG tries to do
accounting on the latter. Accounting on the former is extremely
suspect.
So we need a patch that:
- Deletes the IRQF_SAMPLE_RANDOM mention in
On 06/13/2011 05:39 PM, Kent Borg wrote:
I was assuming that drivers, responding to an interrupt from some
external event, would want to make this call.
Such as a network driver.
Those already are doing this.
Two points:
1. Why look at the high-order bits? How are they going to have
