From 61b8ba69f7a9540ed00576504528ce439f0286f5 Mon Sep 17 00:00:00 2001 From: Steven Luong Date: Wed, 2 Oct 2019 07:33:48 -0700 Subject: devices: vhost not reading packets from vring In a rare event, after the vhost protocol message exchange has finished and the interface had been brought up successfully, the driver MAY still change its mind about the memory regions by sending new memory maps via SET_MEM_TABLE. Upon processing SET_MEM_TABLE, VPP invalidates the old memory regions and the descriptor tables. But it does not re-compute the new descriptor tables based on the new memory maps. Since VPP does not have the descriptor tables, it does not read the packets from the vring. In the normal working case, after SET_MEM_TABLE, the driver follows up with SET_VRING_ADDRESS which VPP computes the descriptor tables. The fix is to stash away the descriptor table addresses from SET_VRING_ADDRESS. Re-compute the new descriptor tables when processing SET_MEM_TABLE if descriptor table addresses are known. Type: fix Ticket: VPP-1784 Signed-off-by: Steven Luong Change-Id: I3361f14c3a0372b8d07943eb6aa4b3a3f10708f9 --- src/vnet/devices/virtio/vhost_user.c | 22 ++++++++++++++++++++++ src/vnet/devices/virtio/vhost_user.h | 3 +++ 2 files changed, 25 insertions(+) diff --git a/src/vnet/devices/virtio/vhost_user.c b/src/vnet/devices/virtio/vhost_user.c index a18313b2038..c61828eb6c0 100644 --- a/src/vnet/devices/virtio/vhost_user.c +++ b/src/vnet/devices/virtio/vhost_user.c @@ -557,6 +557,24 @@ vhost_user_socket_read (clib_file_t * uf) vui->nregions++; } + + /* + * Re-compute desc, used, and avail descriptor table if vring address + * is set. + */ + for (q = 0; q < VHOST_VRING_MAX_N; q++) + { + if (vui->vrings[q].desc_user_addr && + vui->vrings[q].used_user_addr && vui->vrings[q].avail_user_addr) + { + vui->vrings[q].desc = + map_user_mem (vui, vui->vrings[q].desc_user_addr); + vui->vrings[q].used = + map_user_mem (vui, vui->vrings[q].used_user_addr); + vui->vrings[q].avail = + map_user_mem (vui, vui->vrings[q].avail_user_addr); + } + } vlib_worker_thread_barrier_release (vm); break; @@ -600,6 +618,10 @@ vhost_user_socket_read (clib_file_t * uf) goto close_socket; } + vui->vrings[msg.state.index].desc_user_addr = msg.addr.desc_user_addr; + vui->vrings[msg.state.index].used_user_addr = msg.addr.used_user_addr; + vui->vrings[msg.state.index].avail_user_addr = msg.addr.avail_user_addr; + vlib_worker_thread_barrier_sync (vm); vui->vrings[msg.state.index].desc = desc; vui->vrings[msg.state.index].used = used; diff --git a/src/vnet/devices/virtio/vhost_user.h b/src/vnet/devices/virtio/vhost_user.h index 7dadfed2334..7ebea9336af 100644 --- a/src/vnet/devices/virtio/vhost_user.h +++ b/src/vnet/devices/virtio/vhost_user.h @@ -237,6 +237,9 @@ typedef struct vring_desc_t *desc; vring_avail_t *avail; vring_used_t *used; + uword desc_user_addr; + uword used_user_addr; + uword avail_user_addr; f64 int_deadline; u8 started; u8 enabled; -- cgit 1.2.3-korg