On Sat, Oct 13, 2018 at 10:09:52AM -0400, tedheadster wrote: > Christoph, > here is all of the newly patched dmesg output. I also added > 'aic7xxx.a9c7xxx=verbose' for extra information. Hi Matthew, it seems like we do for some reason never actually enable swiotlb for 32-bit x86. Before my commit the block bounce buffering papered over that for networking, Please try this patch: diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c index 661583662430..71c0b01d93b1 100644 --- a/arch/x86/kernel/pci-swiotlb.c +++ b/arch/x86/kernel/pci-swiotlb.c @@ -42,10 +42,8 @@ IOMMU_INIT_FINISH(pci_swiotlb_detect_override, int __init pci_swiotlb_detect_4gb(void) { /* don't initialize swiotlb if iommu=off (no_iommu=1) */ -#ifdef CONFIG_X86_64 if (!no_iommu && max_possible_pfn > MAX_DMA32_PFN) swiotlb = 1; -#endif /* * If SME is active then swiotlb will be set to 1 so that bounce