Commit 0b22bd0ba0d500ab40e7673c591c594ec5447342
Committed by
Rusty Russell
Rusty Russell
1 parent
964fe080d9
Exists in
master
and in
7 other branches
virtio-pci: fix per-vq MSI-X request logic
Commit f68d24082e22ccee3077d11aeb6dc5354f0ca7f1 in 2.6.32-rc1 broke requesting IRQs for per-VQ MSI-X vectors: - vector number was used instead of the vector itself - we try to request an IRQ for VQ which does not have a callback handler This is a regression that causes warnings in kernel log, potentially lower performance as we need to scan vq list, and might cause system failure if the interrupt requested is in fact needed by another system. This was not noticed earlier because in most cases we were falling back on shared interrupt for all vqs. The warnings often look like this: virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X virtio-pci 0000:00:03.0: irq 28 for MSI/MSI-X IRQ handler type mismatch for IRQ 1 current handler: i8042 Pid: 2400, comm: modprobe Tainted: G W 2.6.32-rc3-11952-gf3ed8d8-dirty #1 Call Trace: [<ffffffff81072aed>] ? __setup_irq+0x299/0x304 [<ffffffff81072ff3>] ? request_threaded_irq+0x144/0x1c1 [<ffffffff813455af>] ? vring_interrupt+0x0/0x30 [<ffffffff81346598>] ? vp_try_to_find_vqs+0x583/0x5c7 [<ffffffffa0015188>] ? skb_recv_done+0x0/0x34 [virtio_net] [<ffffffff81346609>] ? vp_find_vqs+0x2d/0x83 [<ffffffff81345d00>] ? vp_get+0x3c/0x4e [<ffffffffa0016373>] ? virtnet_probe+0x2f1/0x428 [virtio_net] [<ffffffffa0015188>] ? skb_recv_done+0x0/0x34 [virtio_net] [<ffffffffa00150d8>] ? skb_xmit_done+0x0/0x39 [virtio_net] [<ffffffff8110ab92>] ? sysfs_do_create_link+0xcb/0x116 [<ffffffff81345cc2>] ? vp_get_status+0x14/0x16 [<ffffffff81345464>] ? virtio_dev_probe+0xa9/0xc8 [<ffffffff8122b11c>] ? driver_probe_device+0x8d/0x128 [<ffffffff8122b206>] ? __driver_attach+0x4f/0x6f [<ffffffff8122b1b7>] ? __driver_attach+0x0/0x6f [<ffffffff8122a9f9>] ? bus_for_each_dev+0x43/0x74 [<ffffffff8122a374>] ? bus_add_driver+0xea/0x22d [<ffffffff8122b4a3>] ? driver_register+0xa7/0x111 [<ffffffffa001a000>] ? init+0x0/0xc [virtio_net] [<ffffffff81009051>] ? do_one_initcall+0x50/0x148 [<ffffffff8106e117>] ? sys_init_module+0xc5/0x21a [<ffffffff8100af02>] ? system_call_fastpath+0x16/0x1b virtio-pci 0000:00:03.0: irq 26 for MSI/MSI-X virtio-pci 0000:00:03.0: irq 27 for MSI/MSI-X Reported-by: Marcelo Tosatti <mtosatti@redhat.com> Reported-by: Shirley Ma <xma@us.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Showing 1 changed file with 15 additions and 12 deletions Side-by-side Diff
drivers/virtio/virtio_pci.c
| ... | ... | @@ -530,19 +530,22 @@ |
| 530 | 530 | err = PTR_ERR(vqs[i]); |
| 531 | 531 | goto error_find; |
| 532 | 532 | } |
| 533 | + | |
| 534 | + if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR) | |
| 535 | + continue; | |
| 536 | + | |
| 533 | 537 | /* allocate per-vq irq if available and necessary */ |
| 534 | - if (vp_dev->per_vq_vectors) { | |
| 535 | - snprintf(vp_dev->msix_names[msix_vec], | |
| 536 | - sizeof *vp_dev->msix_names, | |
| 537 | - "%s-%s", | |
| 538 | - dev_name(&vp_dev->vdev.dev), names[i]); | |
| 539 | - err = request_irq(msix_vec, vring_interrupt, 0, | |
| 540 | - vp_dev->msix_names[msix_vec], | |
| 541 | - vqs[i]); | |
| 542 | - if (err) { | |
| 543 | - vp_del_vq(vqs[i]); | |
| 544 | - goto error_find; | |
| 545 | - } | |
| 538 | + snprintf(vp_dev->msix_names[msix_vec], | |
| 539 | + sizeof *vp_dev->msix_names, | |
| 540 | + "%s-%s", | |
| 541 | + dev_name(&vp_dev->vdev.dev), names[i]); | |
| 542 | + err = request_irq(vp_dev->msix_entries[msix_vec].vector, | |
| 543 | + vring_interrupt, 0, | |
| 544 | + vp_dev->msix_names[msix_vec], | |
| 545 | + vqs[i]); | |
| 546 | + if (err) { | |
| 547 | + vp_del_vq(vqs[i]); | |
| 548 | + goto error_find; | |
| 546 | 549 | } |
| 547 | 550 | } |
| 548 | 551 | return 0; |