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    SubjectRe: Hang on "echo b > /proc/sysrq-trigger"
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    Hi Eric

    Keep a quick update...

    >> I would check with your BIOS folks and perhaps play with the kernel
    >> option.  The most reliable way to peform a reset is to trigger a board
    >> reset by writing to 0xcf9 or a similar register.  I expect your BIOS
    >> does that and you can probably get the kernel to do that.  I would
    >> definitely test to see if you can write to the mostly standard
    >> 0xcf9 register directly from the kernel and trigger a reset directly.
    >>

    Thank you very much for this. We have tried with reboot=p, which is
    writing to the 0xCF9 register directly, and the test has been running
    good for the past 9 days. Will keep monitoring it.

    Also, I have also added a delay in the KBD reboot, which appears to
    have made the reboot reliable (running good for past 8 days, before it
    would hang after 2 days):
    -----------------------
    kb_wait();
    udelay(150); <------ Increased from 50
    outb(0xfe, 0x64); /* pulse reset low */
    udelay(50);
    -----------------------

    Looks like the code may be issuing the reboot a bit too early after
    returning from kb_wait().

    Regards
    Keith
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