The patch titled x86: enable GART-IOMMU only after setting up protection methods has been added to the -mm tree. Its filename is x86-enable-gart-iommu-only-after-setting-up-protection-methods.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: x86: enable GART-IOMMU only after setting up protection methods From: Mark Langsdorf <mark.langsdorf@xxxxxxx> 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. Signed-off-by: Mark Langsdorf <mark.langsdorf@xxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/pci-gart_64.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff -puN arch/x86/kernel/pci-gart_64.c~x86-enable-gart-iommu-only-after-setting-up-protection-methods arch/x86/kernel/pci-gart_64.c --- a/arch/x86/kernel/pci-gart_64.c~x86-enable-gart-iommu-only-after-setting-up-protection-methods +++ a/arch/x86/kernel/pci-gart_64.c @@ -38,6 +38,7 @@ #include <asm/swiotlb.h> #include <asm/dma.h> #include <asm/k8.h> +#include <asm/tlbflush.h> static unsigned long iommu_bus_base; /* GART remapping area (physical) */ static unsigned long iommu_size; /* size of remapping area bytes */ @@ -686,9 +687,9 @@ static __init int init_k8_gatt(struct ag if (set_memory_uc((unsigned long)gatt, gatt_size >> PAGE_SHIFT)) panic("Could not set GART PTEs to uncacheable pages"); - agp_gatt_table = gatt; + wbinvd(); - enable_gart_translations(); + agp_gatt_table = gatt; error = sysdev_class_register(&gart_sysdev_class); if (!error) @@ -859,6 +860,11 @@ void __init gart_iommu_init(void) for (i = EMERGENCY_PAGES; i < iommu_pages; i++) iommu_gatt_base[i] = gart_unmapped_entry; + wbinvd(); + flush_tlb_all(); + + enable_gart_translations(); + flush_gart(); dma_ops = &gart_dma_ops; } _ Patches currently in -mm which might be from mark.langsdorf@xxxxxxx are x86-enable-gart-iommu-only-after-setting-up-protection-methods.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html