Re: [Qemu-devel] [PATCH][TRIVIAL] i6300esb: fix timer overflow

["Richard W.M. Jones" <rjones@redhat.com>]

On Tue, Aug 04, 2015 at 10:27:31AM +0200, Laurent Vivier wrote:
> --- a/hw/watchdog/wdt_i6300esb.c
> +++ b/hw/watchdog/wdt_i6300esb.c
> @@ -136,7 +136,7 @@ static void i6300esb_restart_timer(I6300State *d, int stage)
>       * multiply here can exceed 64-bits, before we divide by 33MHz, so
>       * we use a higher-precision intermediate result.
>       */
> -    timeout = muldiv64(get_ticks_per_sec(), timeout, 33000000);
> +    timeout = muldiv64(timeout, get_ticks_per_sec(), 33000000);
>  
>      i6300esb_debug("stage %d, timeout %" PRIi64 "\n", d->stage, timeout);

Here are the test results for this (v2) patch:

  Requested timeout     Observed timeout
       60                    58
      120                   120
      250                   253
      270                   274
      500                   507
      520                   529
     1010                  1026
     1030                  1045
     2046                  2078
     2500    ioctl: WDIOC_SETTIMEOUT: error setting timeout: Invalid argument

Rich.

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