diff options
-rw-r--r-- | Documentation/x86/x86_64/boot-options.txt | 5 | ||||
-rw-r--r-- | arch/x86/kernel/pci-dma.c | 4 |
2 files changed, 2 insertions, 7 deletions
diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt index 341588ec4e29..8d109ef67ab6 100644 --- a/Documentation/x86/x86_64/boot-options.txt +++ b/Documentation/x86/x86_64/boot-options.txt @@ -236,11 +236,6 @@ IOMMU (input/output memory management unit) nomerge Don't do scatter-gather (SG) merging. noaperture Ask the IOMMU not to touch the aperture for AGP. noagp Don't initialize the AGP driver and use full aperture. - allowdac Allow double-address cycle (DAC) mode, i.e. DMA >4GB. - DAC is used with 32-bit PCI to push a 64-bit address in - two cycles. When off all DMA over >4GB is forced through - an IOMMU or software bounce buffering. - nodac Forbid DAC mode, i.e. DMA >4GB. panic Always panic when IOMMU overflows. calgary Use the Calgary IOMMU if it is available diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index b65b0d7072f1..b523414bc323 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -122,9 +122,9 @@ static __init int iommu_setup(char *p) if (!strncmp(p, "forcesac", 8)) pr_warn("forcesac option ignored.\n"); if (!strncmp(p, "allowdac", 8)) - forbid_dac = 0; + pr_warn("allowdac option ignored.\n"); if (!strncmp(p, "nodac", 5)) - forbid_dac = 1; + pr_warn("nodac option ignored.\n"); if (!strncmp(p, "usedac", 6)) { forbid_dac = -1; return 1; |