diff options
Diffstat (limited to 'arch/x86/kernel/pci-gart_64.c')
| -rw-r--r-- | arch/x86/kernel/pci-gart_64.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c index 65f6acb025c..faf3229f8fb 100644 --- a/arch/x86/kernel/pci-gart_64.c +++ b/arch/x86/kernel/pci-gart_64.c @@ -749,6 +749,15 @@ void __init gart_iommu_init(void) */ set_memory_np((unsigned long)__va(iommu_bus_base), iommu_size >> PAGE_SHIFT); + /* + * Tricky. The GART table remaps the physical memory range, + * so the CPU wont notice potential aliases and if the memory + * is remapped to UC later on, we might surprise the PCI devices + * with a stray writeout of a cacheline. So play it sure and + * do an explicit, full-scale wbinvd() _after_ having marked all + * the pages as Not-Present: + */ + wbinvd(); /* * Try to workaround a bug (thanks to BenH) |