[PATCH] Document iommu=panic

Signed-off-by: Andi Kleen <ak@suse.de>

diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index e97a4c8..74b77f9 100644 (file)
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -203,6 +203,7 @@ IOMMU
            When off all DMA over >4GB is forced through an IOMMU or bounce
            buffering.
    nodac    Forbid DMA >4GB
+   panic    Always panic when IOMMU overflows
 
   swiotlb=pages[,force]
 

diff --git a/arch/x86_64/kernel/pci-dma.c b/arch/x86_64/kernel/pci-dma.c
index 58be792..f8d8574 100644 (file)
--- a/arch/x86_64/kernel/pci-dma.c
+++ b/arch/x86_64/kernel/pci-dma.c
@@ -245,6 +245,7 @@ EXPORT_SYMBOL(dma_set_mask);
    noaperture Don't touch the aperture for AGP.
    allowdac Allow DMA >4GB
    nodac    Forbid DMA >4GB
+   panic    Force panic when IOMMU overflows
 */
 __init int iommu_setup(char *p)
 {