Re: Calibration issues with USB disc present.

From: john stultz (johnstul_at_us.ibm.com)
Date: 11/14/05

  • Next message: Alan Cox: "Re: [2.6 patch] i386: always use 4k stacks" 
    To: Greg KH <greg@kroah.com>
Date:	Mon, 14 Nov 2005 11:58:58 -0800

    On Mon, 2005-11-14 at 10:49 -0800, Greg KH wrote:
    > On Mon, Nov 14, 2005 at 10:56:05AM -0800, George Anzinger wrote:
    > > Greg KH wrote:
    > > >On Sat, Nov 12, 2005 at 08:06:37AM -0800, George Anzinger wrote:
    > > >>Greg KH wrote:
    > > >On these boxes, I'd just recommend disabling USB legacy support
    > > >completly, if possible. And then complain loudly to the vendor to fix
    > > >their BIOS.
    > >
    > > But if one is booting from that device...
    >
    > Booting from a USB device? I can see this happening when installing a
    > distro, and you boot from the USB cdrom, but not for "normal"
    > operations.
    >
    > Oh well, publicly mock the manufacturer for doing horrible things in
    > their BIOS and then no one will buy the boxes, and we will not have
    > problems :)

    I suspect the right fix is in-between. We should try to push hardware
    makers away from using SMIs recklessly, but we should also do our best
    to work around those that don't. The same problems crop up w/
    virtualization where time-based calibration may be interrupted.

    George, again, there has been some SMI resistant delay calibration code
    added recently. You mentioned this problem was seen on 2.4 kernel, so
    you could verify that the new code in 2.6.14 works and if so, try
    backporting it.

    If not we need to see what else we can do about improving delay
    calibration (its a similar tick-based problem to what I'm addressing
    with the timeofday rework) or reducing the use of delay by using
    something else.

    thanks
    -john

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  • Next message: Alan Cox: "Re: [2.6 patch] i386: always use 4k stacks"

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