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    SubjectRe: [PATCH] Enable GART-IOMMU only after setting up protection methods
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    On Wed, Apr 8, 2009 at 2:08 PM, Mark Langsdorf <mark.langsdorf@amd.com> wrote:
    > The current code to set up the GART as an IOMMU enables GART
    > translations before it removes the aperture from the kernel
    > memory map, sets the GART PTEs to UC, sets up the guard and
    > scratch pages, or does a wbinvd().  This leaves the possibility
    > of cache aliasing open and can cause system crashes.
    >
    > Re-order the code and add tlbflush so as to enable the
    > GART translations only after all safeguards are in place and
    > the tlb has been flushed.
    >
    > AMD has tested this patch and seen no adverse effects.

    how about system with AGP card and more than 4g system RAM?

    also it seems flush_gart() in init_k8_gatt() and gart_iommu_init()
    could be removed?

    YH
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