On Thu, Aug 28, 2014 at 12:44 AM, Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote: > On 27/08/14 23:50, Andy Lutomirski wrote: >> This fixes virtio on Xen guests as well as on any other platform >> that uses virtio_pci on which physical addresses don't match bus >> addresses. >> >> This can be tested with: >> >> virtme-run --xen xen --kimg arch/x86/boot/bzImage --console >> >> using virtme from here: >> >> https://git.kernel.org/cgit/utils/kernel/virtme/virtme.git >> >> Without these patches, the guest hangs forever. With these patches, >> everything works. >> >> This should be safe on all platforms that I'm aware of. That >> doesn't mean that there isn't anything that I missed. >> >> Changes from v1: >> - Using the DMA API is optional now. It would be nice to improve the >> DMA API to the point that it could be used unconditionally, but s390 >> proves that we're not there yet. >> - Includes patch 4, which fixes DMA debugging warnings from virtio_net. >> >> Andy Lutomirski (4): >> virtio_ring: Remove sg_next indirection >> virtio_ring: Support DMA APIs if requested >> virtio_pci: Use the DMA API for virtqueues >> virtio_net: Stop doing DMA from the stack >> >> drivers/lguest/lguest_device.c | 3 +- >> drivers/misc/mic/card/mic_virtio.c | 2 +- >> drivers/net/virtio_net.c | 53 +++++--- >> drivers/remoteproc/remoteproc_virtio.c | 4 +- >> drivers/s390/kvm/kvm_virtio.c | 2 +- >> drivers/s390/kvm/virtio_ccw.c | 4 +- >> drivers/virtio/virtio_mmio.c | 5 +- >> drivers/virtio/virtio_pci.c | 35 ++++-- >> drivers/virtio/virtio_ring.c | 219 ++++++++++++++++++++++++++------- >> include/linux/virtio_ring.h | 1 + >> tools/virtio/linux/virtio.h | 1 + >> tools/virtio/virtio_test.c | 2 +- >> tools/virtio/vringh_test.c | 3 +- >> 13 files changed, 253 insertions(+), 81 deletions(-) >> > > Patches were applied on top of 3.16. > > block seems to work, with net a simple ping works, iperf causes this: I neither see the bug, nor can I reproduce it on x86_64 on KVM. I doubt that dma vs. non-dma is relevant. I tried -net user a -net tap with iperf running in both directions. I also tried switching virtio_pci into non-DMA-API mode. No errors. Is there any chance that you could instrument that BUG_ON to print n, i, in_sgs, out_sgs, total_sg, total_in, and total_out? I assume this is some oddity with patch 1, but I'm mystified. Thanks, Andy > > [ 8.643981] ------------[ cut here ]------------ > [ 8.643986] kernel BUG at drivers/virtio/virtio_ring.c:245! > [ 8.644036] illegal operation: 0001 [#1] SMP > [ 8.644039] Modules linked in: virtio_net virtio_blk dm_multipath sunrpc > [ 8.644046] CPU: 0 PID: 1291 Comm: iperf Not tainted 3.16.0+ #130 > [ 8.644048] task: 00000000018ee4c0 ti: 0000000022098000 task.ti: 0000000022098000 > [ 8.644051] Krnl PSW : 0704d00180000000 0000000000421618 (virtqueue_add_outbuf+0x2e4/0x340) > [ 8.644066] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3 > Krnl GPRS: 00000000299f8a80 0000000000000000 0000000000000001 000003d100000000 > [ 8.644070] 00000000004214de 0000000000000e2c 0000000000000001 0000000000000002 > [ 8.644072] 00000000299f8a40 0000000000000001 00000000299f8a40 0000000000000000 > [ 8.644074] 0000000028077608 00000000287ec000 0000000000421548 000000002209b7b0 > [ 8.644085] Krnl Code: 000000000042160a: d060a7a90000 trtr 1961(97,%r10),0 > 0000000000421610: a7f4ff07 brc 15,42141e > #0000000000421614: a7f40001 brc 15,421616 > >0000000000421618: a7c8fffb lhi %r12,-5 > 000000000042161c: a7f4ff46 brc 15,4214a8 > 0000000000421620: a7f40001 brc 15,421622 > 0000000000421624: b9040021 lgr %r2,%r1 > 0000000000421628: c030001c3569 larl %r3,7a80fa > [ 8.644106] Call Trace: > [ 8.644110] ([<00000000004214de>] virtqueue_add_outbuf+0x1aa/0x340) > [ 8.644114] [<000003ff80174466>] start_xmit+0x1e6/0x49c [virtio_net] > [ 8.644119] [<000000000050571a>] dev_hard_start_xmit+0x346/0x600 > [ 8.644123] [<000000000052a43c>] sch_direct_xmit+0xe8/0x1e8 > [ 8.644126] [<0000000000505be8>] __dev_queue_xmit+0x214/0x4ec > [ 8.644131] [<000000000054a476>] ip_finish_output+0x436/0x90c > [ 8.644134] [<000000000054b7c0>] ip_queue_xmit+0x170/0x3e8 > [ 8.644137] [<00000000005636ca>] tcp_transmit_skb+0x462/0x984 > [ 8.644140] [<0000000000564870>] tcp_write_xmit+0x220/0xd0c > [ 8.644143] [<00000000005653a2>] tcp_push_one+0x46/0x58 > [ 8.644145] [<00000000005568b4>] tcp_sendmsg+0xb7c/0xc9c > [ 8.644148] [<00000000004e7514>] sock_aio_write+0x12c/0x158 > [ 8.644153] [<000000000027033c>] do_sync_write+0x80/0xc8 > [ 8.644156] [<0000000000271444>] vfs_write+0x144/0x1d8 > [ 8.644158] [<000000000027192a>] SyS_write+0x62/0xd0 > [ 8.644163] [<000000000062781c>] sysc_tracego+0x14/0x1a > [ 8.644170] [<000003fffd51203c>] 0x3fffd51203c > [ 8.644171] Last Breaking-Event-Address: > [ 8.644174] [<0000000000421614>] virtqueue_add_outbuf+0x2e0/0x340 > -- Andy Lutomirski AMA Capital Management, LLC _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
