Re: IXGBE, IOMMU DMAR DRHD handling fault issue
From: Burakov, Anatoly <hidden>
Date: 2018-02-15 10:28:36
On 14-Feb-18 8:00 PM, Ravi Kerur wrote:
Earlier I was focusing only on DMAR errors and I might have said 'it worked' when I didn't notice them on host when dpdk was started on guest. When trying to send packets out of that interface from guest I did see DMAR errors. I am attaching information you requested. I have enabled log-level=8 and files contain dpdk EAL/PMD logs as well.
Great, now we're on the same page.
Snippets below on host, DMAR fault address from dmesg [351576.998109] DMAR: DRHD: handling fault status reg 702 [351576.998113] DMAR: [DMA Read] Request device [04:10.0] fault addr 257617000 [fault reason 06] PTE Read access is not set on guest (dump phys_mem_layout) Segment 235: phys:0x257600000, len:2097152, virt:0x7fce87e00000, socket_id:0, hugepage_sz:2097152, nchannel:0, nrank:0 ... PMD: ixgbe_dev_rx_queue_setup(): sw_ring=0x7fce87e0f4c0 sw_sc_ring=0x7fce87e07380 hw_ring=0x7fce87e17600 dma_addr=0x257617600 PMD: ixgbe_dev_rx_queue_setup(): sw_ring=0x7fce89c67d40 sw_sc_ring=0x7fce89c5fc00 hw_ring=0x7fce89c6fe80 dma_addr=0x25406fe80 ...
To me this looks like host (i.e. either QEMU or the PF driver) is trying to do DMA using guest-physical (and not host-physical). I'm not too well-versed in how QEMU works, but i'm pretty sure that's not supposed to happen. Is PF also bound to DPDK, or are you using native Linux ixgbe driver? -- Thanks, Anatoly