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DateTue, 25 Jan 2000 13:09:21 -0800 (PST)
FromDavid Whysong <>
SubjectRe: Intel 810 Random Number Generator
On Tue, 25 Jan 2000, Pavel Machek wrote:

>You mean -- like time in jiffies? That is 10msec resolution, do you
>recall?
>
>I think that even bad hw RNG is going to be better than that.

Yeah, 10ms isn't very good (though isn't it 1ms on Alphas?). But
add_timer_randomness() doesn't always use jiffies. I quote from the
source:

#if defined (__i386__)
        if (boot_cpu_data.x86_capability & X86_FEATURE_TSC) {
                __u32 high;
                __asm__(".byte 0x0f,0x31"
                        :"=a" (time), "=d" (high));
                num ^= high;
        } else {
                time = jiffies;
        }
#else
        time = jiffies;
#endif

Dave

David Whysong                                       dwhysong@physics.ucsb.edu
Astrophysics graduate student         University of California, Santa Barbara
My public PGP keys are on my web page - http://www.physics.ucsb.edu/~dwhysong
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