Re: Concurrent access to /dev/urandom

[Jan Engelhardt]

>Even timer interrupts are incredibly unpredictable.  Instructions can
>take
>variable times to complete, and all instructions plus some indeterminate
>cache operations and queue flushing must occur before the CPU can
>even begin to service an interrupt.

Well, don't timer interrupts happen every 1/1000 s (unless, of course, cli() is
in effect)?

>Also of note, there are small
>critical
>sections with interrupts disabled scattered all over the kernel and
>scheduler,
>in addition to varying memory latencies, etc. (NOTE: I am not an arch
>expert

In case you mean the RDTSC, it is of course better than the I8042, for
random-aphy.



Jan Engelhardt
-- 
Gesellschaft fÃr Wissenschaftliche Datenverarbeitung
Am Fassberg, 37077 GÃttingen, www.gwdg.de
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/