x86: fix broken flushing in GART nofullflush path

Impact: remove stale IOTLB entries

In the non-default nofullflush case the GART is only flushed when
next_bit wraps around. But it can happen that an unmap operation unmaps
memory which is behind the current next_bit location. If these addresses
are reused it may result in stale GART IO/TLB entries. Fix this by
setting the GART next_bit always behind an unmapped location.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Joerg Roedel 2008-12-02 20:16:03 +01:00 committed by Ingo Molnar
parent 50cec5c51c
commit dcb7731a18

View file

@ -123,6 +123,8 @@ static void free_iommu(unsigned long offset, int size)
spin_lock_irqsave(&iommu_bitmap_lock, flags);
iommu_area_free(iommu_gart_bitmap, offset, size);
if (offset >= next_bit)
next_bit = offset + size;
spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
}