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    SubjectRe: [PATCH] Re: time() glitch on 2.4.18: solved
    Jim Paris wrote:
    >
    > > > Any comments?
    > >
    > > Have a play with it, if your idea works when you deliberately disturb it
    > > then send in a patch
    >
    > This works well.

    But it does introduce a hiccup in time. One could just do
    an odd read IF that is all that is wrong. Your code could
    also be correcting for other ills...

    -g
    >
    > -jim
    >
    > diff -urN linux-2.4.18/arch/i386/kernel/time.c linux-2.4.18-jim/arch/i386/kernel/time.c
    > --- linux-2.4.18/arch/i386/kernel/time.c Fri Mar 15 18:28:53 2002
    > +++ linux-2.4.18-jim/arch/i386/kernel/time.c Tue Nov 5 11:22:02 2002
    > @@ -501,6 +501,16 @@
    >
    > count = inb_p(0x40); /* read the latched count */
    > count |= inb(0x40) << 8;
    > +
    > + /* Any unpaired read will cause the above to swap MSB/LSB
    > + forever. Try to detect this and reset the counter. */
    > + if (count > LATCH) {
    > + outb_p(0x34, 0x43);
    > + outb_p(LATCH & 0xff, 0x40);
    > + outb(LATCH >> 8, 0x40);
    > + count = LATCH - 1;
    > + }
    > +
    > spin_unlock(&i8253_lock);
    >
    > count = ((LATCH-1) - count) * TICK_SIZE;
    > -
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    --
    George Anzinger george@mvista.com
    High-res-timers:
    http://sourceforge.net/projects/high-res-timers/
    Preemption patch:
    http://www.kernel.org/pub/linux/kernel/people/rml
    -
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