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    SubjectRe: [PATCH for-2.6.35] virtio-pci: disable msi at startup
    On Wed, Jun 23, 2010 at 04:59:11PM +0300, Avi Kivity wrote:
    > On 06/10/2010 06:22 PM, Michael S. Tsirkin wrote:
    >> virtio-pci resets the device at startup by writing to the status
    >> register, but this does not clear the pci config space,
    >> specifically msi enable status which affects register
    >> layout.
    >> This breaks things like kdump when they try to use e.g. virtio-blk.
    >> Fix by forcing msi off at startup. Since pci.c already has
    >> a routine to do this, we export and use it instead of duplicating code.
    > Why doesn't a device reset result in msi being cleared?

    This is not a standard function reset. This is virtio specific
    command. So it only clears virtio registers.

    > Shouldn't a reset be equivalent to power cycling?

    If we did this, driver would need to restore registers
    such as BAR etc.

    > --
    > error compiling committee.c: too many arguments to function

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