| Message ID | 20240711131424.181615-2-ppandit@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Postcopy migration and vhost-user errors | expand |
On Thu, Jul 11, 2024 at 06:44:23PM +0530, Prasad Pandit wrote: > From: Prasad Pandit <pjp@fedoraproject.org> > > QEMU threads use vhost_user_write/read calls to send > and receive messages from a vhost-user device. When multiple > threads communicate with the same vhost-user device, they can > receive each other's messages, resulting in an erroneous state. > > vhost_user_read_header: > 700871,700871: Failed to read msg header. Flags 0x0 instead of 0x5. > vhost_device_iotlb_miss: > 700871,700871: Fail to update device iotlb > vhost_user_postcopy_end: > 700871,700900: Failed to receive reply to postcopy_end > vhost_user_read_header: > 700871,700871: Failed to read msg header. Flags 0x0 instead of 0x5. > > Here fault thread seems to end the postcopy migration while > another thread is starting the vhost-user device. > > Add a rw lock to hold for one vhost_user_write/read cycle > and avoid such race conditions. > > Suggested-by: Peter Xu <peterx@redhat.com> > Signed-off-by: Prasad Pandit <pjp@fedoraproject.org> Could you supply a Fixes tag here? What commit introduced the race? > --- > hw/virtio/vhost-user.c | 423 +++++++++++++++++++-------------- > include/hw/virtio/vhost-user.h | 3 + > 2 files changed, 254 insertions(+), 172 deletions(-) > > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > index 00561daa06..99881c487f 100644 > --- a/hw/virtio/vhost-user.c > +++ b/hw/virtio/vhost-user.c > @@ -24,6 +24,7 @@ > #include "qemu/main-loop.h" > #include "qemu/uuid.h" > #include "qemu/sockets.h" > +#include "qemu/lockable.h" > #include "sysemu/runstate.h" > #include "sysemu/cryptodev.h" > #include "migration/postcopy-ram.h" > @@ -433,6 +434,8 @@ int vhost_user_gpu_set_socket(struct vhost_dev *dev, int fd) > static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, > struct vhost_log *log) > { > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int fds[VHOST_USER_MAX_RAM_SLOTS]; > size_t fd_num = 0; > bool shmfd = virtio_has_feature(dev->protocol_features, > @@ -455,23 +458,25 @@ static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, > fds[fd_num++] = log->fd; > } > > - ret = vhost_user_write(dev, &msg, fds, fd_num); > - if (ret < 0) { > - return ret; > - } > - > - if (shmfd) { > - msg.hdr.size = 0; > - ret = vhost_user_read(dev, &msg); > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, fds, fd_num); > if (ret < 0) { > return ret; > } > > - if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) { > - error_report("Received unexpected msg type. " > - "Expected %d received %d", > - VHOST_USER_SET_LOG_BASE, msg.hdr.request); > - return -EPROTO; > + if (shmfd) { > + msg.hdr.size = 0; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > + > + if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) { > + error_report("Received unexpected msg type. " > + "Expected %d received %d", > + VHOST_USER_SET_LOG_BASE, msg.hdr.request); > + return -EPROTO; > + } > } > } > > @@ -664,6 +669,7 @@ static int send_remove_regions(struct vhost_dev *dev, > bool reply_supported) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > struct vhost_memory_region *shadow_reg; > int i, fd, shadow_reg_idx, ret; > ram_addr_t offset; > @@ -685,16 +691,18 @@ static int send_remove_regions(struct vhost_dev *dev, > vhost_user_fill_msg_region(®ion_buffer, shadow_reg, 0); > msg->payload.mem_reg.region = region_buffer; > > - ret = vhost_user_write(dev, msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > - > - if (reply_supported) { > - ret = process_message_reply(dev, msg); > - if (ret) { > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, msg, NULL, 0); > + if (ret < 0) { > return ret; > } > + > + if (reply_supported) { > + ret = process_message_reply(dev, msg); > + if (ret) { > + return ret; > + } > + } > } > } > > @@ -725,6 +733,9 @@ static int send_add_regions(struct vhost_dev *dev, > VhostUserMsg msg_reply; > VhostUserMemoryRegion region_buffer; > > + struct VhostUserState *us = u->user; > + QEMU_LOCK_GUARD(&us->vhost_user_rw_lock); > + > for (i = 0; i < nr_add_reg; i++) { > reg = add_reg[i].region; > reg_idx = add_reg[i].reg_idx; > @@ -893,6 +904,7 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, > bool config_mem_slots) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int fds[VHOST_MEMORY_BASELINE_NREGIONS]; > size_t fd_num = 0; > VhostUserMsg msg_reply; > @@ -926,14 +938,16 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, > return ret; > } > > - ret = vhost_user_write(dev, &msg, fds, fd_num); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, fds, fd_num); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg_reply); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg_reply); > + if (ret < 0) { > + return ret; > + } > } > > if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) { > @@ -1005,6 +1019,7 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, > struct vhost_memory *mem) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int fds[VHOST_MEMORY_BASELINE_NREGIONS]; > size_t fd_num = 0; > bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler; > @@ -1044,13 +1059,15 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, > return ret; > } > > - ret = vhost_user_write(dev, &msg, fds, fd_num); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, fds, fd_num); > + if (ret < 0) { > + return ret; > + } > > - if (reply_supported) { > - return process_message_reply(dev, &msg); > + if (reply_supported) { > + return process_message_reply(dev, &msg); > + } > } > } > > @@ -1080,6 +1097,8 @@ static int vhost_user_set_vring_endian(struct vhost_dev *dev, > static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > VhostUserMsg msg = { > .hdr.request = request, > .hdr.flags = VHOST_USER_VERSION, > @@ -1089,14 +1108,16 @@ static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) > return 0; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != request) { > @@ -1129,6 +1150,8 @@ static int vhost_user_write_sync(struct vhost_dev *dev, VhostUserMsg *msg, > bool wait_for_reply) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > if (wait_for_reply) { > bool reply_supported = virtio_has_feature(dev->protocol_features, > @@ -1138,25 +1161,27 @@ static int vhost_user_write_sync(struct vhost_dev *dev, VhostUserMsg *msg, > } > } > > - ret = vhost_user_write(dev, msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - if (wait_for_reply) { > - uint64_t dummy; > + if (wait_for_reply) { > + uint64_t dummy; > > - if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) { > - return process_message_reply(dev, msg); > - } > + if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) { > + return process_message_reply(dev, msg); > + } > > - /* > - * We need to wait for a reply but the backend does not > - * support replies for the command we just sent. > - * Send VHOST_USER_GET_FEATURES which makes all backends > - * send a reply. > - */ > - return vhost_user_get_features(dev, &dummy); > + /* > + * We need to wait for a reply but the backend does not > + * support replies for the command we just sent. > + * Send VHOST_USER_GET_FEATURES which makes all backends > + * send a reply. > + */ > + return vhost_user_get_features(dev, &dummy); > + } > } > > return 0; > @@ -1277,20 +1302,23 @@ static int vhost_user_get_vring_base(struct vhost_dev *dev, > .hdr.size = sizeof(msg.payload.state), > }; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > VhostUserHostNotifier *n = fetch_notifier(u->user, ring->index); > if (n) { > vhost_user_host_notifier_remove(n, dev->vdev); > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_VRING_BASE) { > @@ -1661,6 +1689,7 @@ int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid, > int *dmabuf_fd) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > CharBackend *chr = u->user->chr; > int ret; > VhostUserMsg msg = { > @@ -1669,14 +1698,16 @@ int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid, > }; > memcpy(msg.payload.object.uuid, uuid, sizeof(msg.payload.object.uuid)); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_SHARED_OBJECT) { > @@ -1858,6 +1889,7 @@ static int vhost_setup_backend_channel(struct vhost_dev *dev) > .hdr.flags = VHOST_USER_VERSION, > }; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int sv[2], ret = 0; > bool reply_supported = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_REPLY_ACK); > @@ -1889,15 +1921,16 @@ static int vhost_setup_backend_channel(struct vhost_dev *dev) > msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; > } > > - ret = vhost_user_write(dev, &msg, &sv[1], 1); > - if (ret) { > - goto out; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, &sv[1], 1); > + if (ret) { > + goto out; > + } > > - if (reply_supported) { > - ret = process_message_reply(dev, &msg); > + if (reply_supported) { > + ret = process_message_reply(dev, &msg); > + } > } > - > out: > close(sv[1]); > if (ret) { > @@ -1985,6 +2018,7 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp) > { > #ifdef CONFIG_LINUX > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > CharBackend *chr = u->user->chr; > int ufd; > int ret; > @@ -1993,16 +2027,18 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp) > .hdr.flags = VHOST_USER_VERSION, > }; > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg(errp, "Failed to send postcopy_advise to vhost"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg(errp, "Failed to send postcopy_advise to vhost"); > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg(errp, "Failed to get postcopy_advise reply from vhost"); > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg(errp, "Failed to get postcopy_advise reply from vhost"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_POSTCOPY_ADVISE) { > @@ -2051,16 +2087,19 @@ static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp) > > trace_vhost_user_postcopy_listen(); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg(errp, "Failed to send postcopy_listen to vhost"); > - return ret; > - } > + struct VhostUserState *us = u->user; > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg(errp, "Failed to send postcopy_listen to vhost"); > + return ret; > + } > > - ret = process_message_reply(dev, &msg); > - if (ret) { > - error_setg(errp, "Failed to receive reply to postcopy_listen"); > - return ret; > + ret = process_message_reply(dev, &msg); > + if (ret) { > + error_setg(errp, "Failed to receive reply to postcopy_listen"); > + return ret; > + } > } > > return 0; > @@ -2077,19 +2116,22 @@ static int vhost_user_postcopy_end(struct vhost_dev *dev, Error **errp) > }; > int ret; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > trace_vhost_user_postcopy_end_entry(); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg(errp, "Failed to send postcopy_end to vhost"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg(errp, "Failed to send postcopy_end to vhost"); > + return ret; > + } > > - ret = process_message_reply(dev, &msg); > - if (ret) { > - error_setg(errp, "Failed to receive reply to postcopy_end"); > - return ret; > + ret = process_message_reply(dev, &msg); > + if (ret) { > + error_setg(errp, "Failed to receive reply to postcopy_end"); > + return ret; > + } > } > postcopy_unregister_shared_ufd(&u->postcopy_fd); > close(u->postcopy_fd.fd); > @@ -2359,6 +2401,8 @@ static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu) > bool reply_supported = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_REPLY_ACK); > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_NET_MTU))) { > return 0; > @@ -2372,14 +2416,16 @@ static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu) > msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - /* If reply_ack supported, backend has to ack specified MTU is valid */ > - if (reply_supported) { > - return process_message_reply(dev, &msg); > + /* If reply_ack supported, backend has to ack specified MTU is valid */ > + if (reply_supported) { > + return process_message_reply(dev, &msg); > + } > } > > return 0; > @@ -2396,12 +2442,19 @@ static int vhost_user_send_device_iotlb_msg(struct vhost_dev *dev, > .payload.iotlb = *imsg, > }; > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > + > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > + > + ret = process_message_reply(dev, &msg); > } > > - return process_message_reply(dev, &msg); > + return ret; > } > > > @@ -2414,6 +2467,8 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, > uint32_t config_len, Error **errp) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > VhostUserMsg msg = { > .hdr.request = VHOST_USER_GET_CONFIG, > .hdr.flags = VHOST_USER_VERSION, > @@ -2430,16 +2485,19 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, > > msg.payload.config.offset = 0; > msg.payload.config.size = config_len; > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg_errno(errp, -ret, "vhost_get_config failed"); > - return ret; > - } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg_errno(errp, -ret, "vhost_get_config failed"); > - return ret; > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg_errno(errp, -ret, "vhost_get_config failed"); > + return ret; > + } > + > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg_errno(errp, -ret, "vhost_get_config failed"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_CONFIG) { > @@ -2464,6 +2522,8 @@ static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, > { > int ret; > uint8_t *p; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > bool reply_supported = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_REPLY_ACK); > > @@ -2492,13 +2552,15 @@ static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, > p = msg.payload.config.region; > memcpy(p, data, size); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - if (reply_supported) { > - return process_message_reply(dev, &msg); > + if (reply_supported) { > + return process_message_reply(dev, &msg); > + } > } > > return 0; > @@ -2509,6 +2571,8 @@ static int vhost_user_crypto_create_session(struct vhost_dev *dev, > uint64_t *session_id) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > bool crypto_session = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_CRYPTO_SESSION); > CryptoDevBackendSessionInfo *backend_info = session_info; > @@ -2572,18 +2636,21 @@ static int vhost_user_crypto_create_session(struct vhost_dev *dev, > > msg.payload.session.op_code = backend_info->op_code; > msg.payload.session.session_id = backend_info->session_id; > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_report("vhost_user_write() return %d, create session failed", > - ret); > - return ret; > - } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_report("vhost_user_read() return %d, create session failed", > - ret); > - return ret; > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_report("vhost_user_write() return %d, create session failed", > + ret); > + return ret; > + } > + > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_report("vhost_user_read() return %d, create session failed", > + ret); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_CREATE_CRYPTO_SESSION) { > @@ -2648,6 +2715,7 @@ static int vhost_user_get_inflight_fd(struct vhost_dev *dev, > int fd; > int ret; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > CharBackend *chr = u->user->chr; > VhostUserMsg msg = { > .hdr.request = VHOST_USER_GET_INFLIGHT_FD, > @@ -2662,14 +2730,16 @@ static int vhost_user_get_inflight_fd(struct vhost_dev *dev, > return 0; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_INFLIGHT_FD) { > @@ -2757,6 +2827,7 @@ bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp) > user->memory_slots = 0; > user->notifiers = g_ptr_array_new_full(VIRTIO_QUEUE_MAX / 4, > &vhost_user_state_destroy); > + qemu_mutex_init(&user->vhost_user_rw_lock); > return true; > } > > @@ -2769,6 +2840,7 @@ void vhost_user_cleanup(VhostUserState *user) > user->notifiers = (GPtrArray *) g_ptr_array_free(user->notifiers, true); > memory_region_transaction_commit(); > user->chr = NULL; > + qemu_mutex_destroy(&user->vhost_user_rw_lock); > } > > > @@ -2882,6 +2954,7 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, > { > int ret; > struct vhost_user *vu = dev->opaque; > + struct VhostUserState *us = vu->user; > VhostUserMsg msg = { > .hdr = { > .request = VHOST_USER_SET_DEVICE_STATE_FD, > @@ -2902,19 +2975,21 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, > return -ENOTSUP; > } > > - ret = vhost_user_write(dev, &msg, &fd, 1); > - close(fd); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to send SET_DEVICE_STATE_FD message"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, &fd, 1); > + close(fd); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to send SET_DEVICE_STATE_FD message"); > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to receive SET_DEVICE_STATE_FD reply"); > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to receive SET_DEVICE_STATE_FD reply"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_SET_DEVICE_STATE_FD) { > @@ -2951,6 +3026,8 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, > > static int vhost_user_check_device_state(struct vhost_dev *dev, Error **errp) > { > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int ret; > VhostUserMsg msg = { > .hdr = { > @@ -2965,18 +3042,20 @@ static int vhost_user_check_device_state(struct vhost_dev *dev, Error **errp) > return -ENOTSUP; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to send CHECK_DEVICE_STATE message"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to send CHECK_DEVICE_STATE message"); > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to receive CHECK_DEVICE_STATE reply"); > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to receive CHECK_DEVICE_STATE reply"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_CHECK_DEVICE_STATE) { > diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h > index 324cd8663a..387ab6da2e 100644 > --- a/include/hw/virtio/vhost-user.h > +++ b/include/hw/virtio/vhost-user.h > @@ -67,6 +67,9 @@ typedef struct VhostUserState { > GPtrArray *notifiers; > int memory_slots; > bool supports_config; > + > + /* Hold lock for vhost_user_write/read cycle */ > + QemuMutex vhost_user_rw_lock; > } VhostUserState; > > /** > -- > 2.45.2
On Thu, Jul 11, 2024 at 06:44:23PM +0530, Prasad Pandit wrote: > From: Prasad Pandit <pjp@fedoraproject.org> > > QEMU threads use vhost_user_write/read calls to send > and receive messages from a vhost-user device. When multiple > threads communicate with the same vhost-user device, they can > receive each other's messages, resulting in an erroneous state. > > vhost_user_read_header: > 700871,700871: Failed to read msg header. Flags 0x0 instead of 0x5. > vhost_device_iotlb_miss: > 700871,700871: Fail to update device iotlb > vhost_user_postcopy_end: > 700871,700900: Failed to receive reply to postcopy_end > vhost_user_read_header: > 700871,700871: Failed to read msg header. Flags 0x0 instead of 0x5. > > Here fault thread seems to end the postcopy migration while > another thread is starting the vhost-user device. > > Add a rw lock to hold for one vhost_user_write/read cycle > and avoid such race conditions. > > Suggested-by: Peter Xu <peterx@redhat.com> > Signed-off-by: Prasad Pandit <pjp@fedoraproject.org> > --- > hw/virtio/vhost-user.c | 423 +++++++++++++++++++-------------- > include/hw/virtio/vhost-user.h | 3 + I apologize if I suggested WITH_QEMU_LOCK_GUARD when we talked.. I don't remember which one I suggested, but in this case IIUC it'll be much easier to review if you use the other sister function QEMU_LOCK_GUARD() instead.. That should make the diff much, much less.
On Thu, 11 Jul 2024 at 21:12, Peter Xu <peterx@redhat.com> wrote: > I apologize if I suggested WITH_QEMU_LOCK_GUARD when we talked.. I don't > remember which one I suggested, but in this case IIUC it'll be much easier > to review if you use the other sister function QEMU_LOCK_GUARD() > instead.. That should make the diff much, much less. * Yes, QEMU_LOCK_GUARD simplifies the diff, but it may extend the time for which lock is held, delaying other threads, is that okay? Thank you. --- - Prasad
On Thu, 11 Jul 2024 at 20:11, Michael S. Tsirkin <mst@redhat.com> wrote:
> Could you supply a Fixes tag here? What commit introduced the race?
'postcopy_end' message was added by:
-> https://github.com/qemu/qemu/commit/46343570c06e63b4499f619011df80f91349cd49
Not sure if its race condition also began with it. It is not clear if
the front-end should allow multiple threads to talk to the same
vhost-user device.
Thank you.
---
- Prasad
On Mon, Jul 15, 2024 at 01:44:00PM +0530, Prasad Pandit wrote: > On Thu, 11 Jul 2024 at 21:12, Peter Xu <peterx@redhat.com> wrote: > > I apologize if I suggested WITH_QEMU_LOCK_GUARD when we talked.. I don't > > remember which one I suggested, but in this case IIUC it'll be much easier > > to review if you use the other sister function QEMU_LOCK_GUARD() > > instead.. That should make the diff much, much less. > > * Yes, QEMU_LOCK_GUARD simplifies the diff, but it may extend the time > for which lock is held, delaying other threads, is that okay? I think it shouldn't be a major deal in most cases, if the extended cycles only cover a bunch of instructions. In special case we can still use WITH_QEMU_LOCK_GUARD, but I'd start with the simple first and only switch if necessary. Thanks,
On Mon, 15 Jul 2024 at 18:57, Peter Xu <peterx@redhat.com> wrote: > I think it shouldn't be a major deal in most cases, if the extended cycles > only cover a bunch of instructions. In special case we can still use > WITH_QEMU_LOCK_GUARD, but I'd start with the simple first and only switch > if necessary. * Okay, will send patch v2. Thank you. --- - Prasad
On Thu, Jul 11, 2024 at 06:44:23PM +0530, Prasad Pandit wrote: > From: Prasad Pandit <pjp@fedoraproject.org> > > QEMU threads use vhost_user_write/read calls to send > and receive messages from a vhost-user device. When multiple > threads communicate with the same vhost-user device, they can > receive each other's messages, resulting in an erroneous state. > > vhost_user_read_header: > 700871,700871: Failed to read msg header. Flags 0x0 instead of 0x5. > vhost_device_iotlb_miss: > 700871,700871: Fail to update device iotlb > vhost_user_postcopy_end: > 700871,700900: Failed to receive reply to postcopy_end > vhost_user_read_header: > 700871,700871: Failed to read msg header. Flags 0x0 instead of 0x5. > > Here fault thread seems to end the postcopy migration while > another thread is starting the vhost-user device. > > Add a rw lock to hold for one vhost_user_write/read cycle > and avoid such race conditions. > > Suggested-by: Peter Xu <peterx@redhat.com> > Signed-off-by: Prasad Pandit <pjp@fedoraproject.org> > --- > hw/virtio/vhost-user.c | 423 +++++++++++++++++++-------------- > include/hw/virtio/vhost-user.h | 3 + > 2 files changed, 254 insertions(+), 172 deletions(-) > > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > index 00561daa06..99881c487f 100644 > --- a/hw/virtio/vhost-user.c > +++ b/hw/virtio/vhost-user.c > @@ -24,6 +24,7 @@ > #include "qemu/main-loop.h" > #include "qemu/uuid.h" > #include "qemu/sockets.h" > +#include "qemu/lockable.h" > #include "sysemu/runstate.h" > #include "sysemu/cryptodev.h" > #include "migration/postcopy-ram.h" > @@ -433,6 +434,8 @@ int vhost_user_gpu_set_socket(struct vhost_dev *dev, int fd) > static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, > struct vhost_log *log) > { > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int fds[VHOST_USER_MAX_RAM_SLOTS]; > size_t fd_num = 0; > bool shmfd = virtio_has_feature(dev->protocol_features, > @@ -455,23 +458,25 @@ static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, > fds[fd_num++] = log->fd; > } > > - ret = vhost_user_write(dev, &msg, fds, fd_num); > - if (ret < 0) { > - return ret; > - } > - > - if (shmfd) { > - msg.hdr.size = 0; > - ret = vhost_user_read(dev, &msg); > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, fds, fd_num); > if (ret < 0) { > return ret; > } > > - if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) { > - error_report("Received unexpected msg type. " > - "Expected %d received %d", > - VHOST_USER_SET_LOG_BASE, msg.hdr.request); > - return -EPROTO; > + if (shmfd) { > + msg.hdr.size = 0; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > + > + if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) { > + error_report("Received unexpected msg type. " > + "Expected %d received %d", > + VHOST_USER_SET_LOG_BASE, msg.hdr.request); > + return -EPROTO; > + } > } > } > > @@ -664,6 +669,7 @@ static int send_remove_regions(struct vhost_dev *dev, > bool reply_supported) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > struct vhost_memory_region *shadow_reg; > int i, fd, shadow_reg_idx, ret; > ram_addr_t offset; > @@ -685,16 +691,18 @@ static int send_remove_regions(struct vhost_dev *dev, > vhost_user_fill_msg_region(®ion_buffer, shadow_reg, 0); > msg->payload.mem_reg.region = region_buffer; > > - ret = vhost_user_write(dev, msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > - > - if (reply_supported) { > - ret = process_message_reply(dev, msg); > - if (ret) { > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, msg, NULL, 0); > + if (ret < 0) { > return ret; > } > + > + if (reply_supported) { > + ret = process_message_reply(dev, msg); > + if (ret) { > + return ret; > + } > + } > } > } > > @@ -725,6 +733,9 @@ static int send_add_regions(struct vhost_dev *dev, > VhostUserMsg msg_reply; > VhostUserMemoryRegion region_buffer; > > + struct VhostUserState *us = u->user; > + QEMU_LOCK_GUARD(&us->vhost_user_rw_lock); > + > for (i = 0; i < nr_add_reg; i++) { > reg = add_reg[i].region; > reg_idx = add_reg[i].reg_idx; > @@ -893,6 +904,7 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, > bool config_mem_slots) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int fds[VHOST_MEMORY_BASELINE_NREGIONS]; > size_t fd_num = 0; > VhostUserMsg msg_reply; > @@ -926,14 +938,16 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, > return ret; > } > > - ret = vhost_user_write(dev, &msg, fds, fd_num); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, fds, fd_num); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg_reply); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg_reply); > + if (ret < 0) { > + return ret; > + } > } > > if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) { > @@ -1005,6 +1019,7 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, > struct vhost_memory *mem) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int fds[VHOST_MEMORY_BASELINE_NREGIONS]; > size_t fd_num = 0; > bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler; > @@ -1044,13 +1059,15 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, > return ret; > } > > - ret = vhost_user_write(dev, &msg, fds, fd_num); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, fds, fd_num); > + if (ret < 0) { > + return ret; > + } > > - if (reply_supported) { > - return process_message_reply(dev, &msg); > + if (reply_supported) { > + return process_message_reply(dev, &msg); > + } > } > } > > @@ -1080,6 +1097,8 @@ static int vhost_user_set_vring_endian(struct vhost_dev *dev, > static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > VhostUserMsg msg = { > .hdr.request = request, > .hdr.flags = VHOST_USER_VERSION, > @@ -1089,14 +1108,16 @@ static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) > return 0; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != request) { > @@ -1129,6 +1150,8 @@ static int vhost_user_write_sync(struct vhost_dev *dev, VhostUserMsg *msg, > bool wait_for_reply) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > if (wait_for_reply) { > bool reply_supported = virtio_has_feature(dev->protocol_features, > @@ -1138,25 +1161,27 @@ static int vhost_user_write_sync(struct vhost_dev *dev, VhostUserMsg *msg, > } > } > > - ret = vhost_user_write(dev, msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - if (wait_for_reply) { > - uint64_t dummy; > + if (wait_for_reply) { > + uint64_t dummy; > > - if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) { > - return process_message_reply(dev, msg); > - } > + if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) { > + return process_message_reply(dev, msg); > + } > > - /* > - * We need to wait for a reply but the backend does not > - * support replies for the command we just sent. > - * Send VHOST_USER_GET_FEATURES which makes all backends > - * send a reply. > - */ > - return vhost_user_get_features(dev, &dummy); > + /* > + * We need to wait for a reply but the backend does not > + * support replies for the command we just sent. > + * Send VHOST_USER_GET_FEATURES which makes all backends > + * send a reply. > + */ > + return vhost_user_get_features(dev, &dummy); > + } > } > > return 0; > @@ -1277,20 +1302,23 @@ static int vhost_user_get_vring_base(struct vhost_dev *dev, > .hdr.size = sizeof(msg.payload.state), > }; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > VhostUserHostNotifier *n = fetch_notifier(u->user, ring->index); > if (n) { > vhost_user_host_notifier_remove(n, dev->vdev); > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_VRING_BASE) { > @@ -1661,6 +1689,7 @@ int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid, > int *dmabuf_fd) > { > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > CharBackend *chr = u->user->chr; > int ret; > VhostUserMsg msg = { > @@ -1669,14 +1698,16 @@ int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid, > }; > memcpy(msg.payload.object.uuid, uuid, sizeof(msg.payload.object.uuid)); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_SHARED_OBJECT) { > @@ -1858,6 +1889,7 @@ static int vhost_setup_backend_channel(struct vhost_dev *dev) > .hdr.flags = VHOST_USER_VERSION, > }; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int sv[2], ret = 0; > bool reply_supported = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_REPLY_ACK); > @@ -1889,15 +1921,16 @@ static int vhost_setup_backend_channel(struct vhost_dev *dev) > msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; > } > > - ret = vhost_user_write(dev, &msg, &sv[1], 1); > - if (ret) { > - goto out; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, &sv[1], 1); > + if (ret) { > + goto out; > + } > > - if (reply_supported) { > - ret = process_message_reply(dev, &msg); > + if (reply_supported) { > + ret = process_message_reply(dev, &msg); > + } > } > - > out: > close(sv[1]); > if (ret) { > @@ -1985,6 +2018,7 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp) > { > #ifdef CONFIG_LINUX > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > CharBackend *chr = u->user->chr; > int ufd; > int ret; > @@ -1993,16 +2027,18 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp) > .hdr.flags = VHOST_USER_VERSION, > }; > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg(errp, "Failed to send postcopy_advise to vhost"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg(errp, "Failed to send postcopy_advise to vhost"); > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg(errp, "Failed to get postcopy_advise reply from vhost"); > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg(errp, "Failed to get postcopy_advise reply from vhost"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_POSTCOPY_ADVISE) { > @@ -2051,16 +2087,19 @@ static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp) > > trace_vhost_user_postcopy_listen(); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg(errp, "Failed to send postcopy_listen to vhost"); > - return ret; > - } > + struct VhostUserState *us = u->user; > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg(errp, "Failed to send postcopy_listen to vhost"); > + return ret; > + } > > - ret = process_message_reply(dev, &msg); > - if (ret) { > - error_setg(errp, "Failed to receive reply to postcopy_listen"); > - return ret; > + ret = process_message_reply(dev, &msg); > + if (ret) { > + error_setg(errp, "Failed to receive reply to postcopy_listen"); > + return ret; > + } > } > > return 0; > @@ -2077,19 +2116,22 @@ static int vhost_user_postcopy_end(struct vhost_dev *dev, Error **errp) > }; > int ret; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > trace_vhost_user_postcopy_end_entry(); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg(errp, "Failed to send postcopy_end to vhost"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg(errp, "Failed to send postcopy_end to vhost"); > + return ret; > + } > > - ret = process_message_reply(dev, &msg); > - if (ret) { > - error_setg(errp, "Failed to receive reply to postcopy_end"); > - return ret; > + ret = process_message_reply(dev, &msg); > + if (ret) { > + error_setg(errp, "Failed to receive reply to postcopy_end"); > + return ret; > + } > } > postcopy_unregister_shared_ufd(&u->postcopy_fd); > close(u->postcopy_fd.fd); > @@ -2359,6 +2401,8 @@ static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu) > bool reply_supported = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_REPLY_ACK); > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > > if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_NET_MTU))) { > return 0; > @@ -2372,14 +2416,16 @@ static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu) > msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - /* If reply_ack supported, backend has to ack specified MTU is valid */ > - if (reply_supported) { > - return process_message_reply(dev, &msg); > + /* If reply_ack supported, backend has to ack specified MTU is valid */ > + if (reply_supported) { > + return process_message_reply(dev, &msg); > + } > } > > return 0; > @@ -2396,12 +2442,19 @@ static int vhost_user_send_device_iotlb_msg(struct vhost_dev *dev, > .payload.iotlb = *imsg, > }; > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > + > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > + > + ret = process_message_reply(dev, &msg); > } > > - return process_message_reply(dev, &msg); > + return ret; > } > > > @@ -2414,6 +2467,8 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, > uint32_t config_len, Error **errp) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > VhostUserMsg msg = { > .hdr.request = VHOST_USER_GET_CONFIG, > .hdr.flags = VHOST_USER_VERSION, > @@ -2430,16 +2485,19 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, > > msg.payload.config.offset = 0; > msg.payload.config.size = config_len; > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg_errno(errp, -ret, "vhost_get_config failed"); > - return ret; > - } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg_errno(errp, -ret, "vhost_get_config failed"); > - return ret; > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg_errno(errp, -ret, "vhost_get_config failed"); > + return ret; > + } > + > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg_errno(errp, -ret, "vhost_get_config failed"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_CONFIG) { > @@ -2464,6 +2522,8 @@ static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, > { > int ret; > uint8_t *p; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > bool reply_supported = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_REPLY_ACK); > > @@ -2492,13 +2552,15 @@ static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, > p = msg.payload.config.region; > memcpy(p, data, size); > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - if (reply_supported) { > - return process_message_reply(dev, &msg); > + if (reply_supported) { > + return process_message_reply(dev, &msg); > + } > } > > return 0; > @@ -2509,6 +2571,8 @@ static int vhost_user_crypto_create_session(struct vhost_dev *dev, > uint64_t *session_id) > { > int ret; > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > bool crypto_session = virtio_has_feature(dev->protocol_features, > VHOST_USER_PROTOCOL_F_CRYPTO_SESSION); > CryptoDevBackendSessionInfo *backend_info = session_info; > @@ -2572,18 +2636,21 @@ static int vhost_user_crypto_create_session(struct vhost_dev *dev, > > msg.payload.session.op_code = backend_info->op_code; > msg.payload.session.session_id = backend_info->session_id; > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_report("vhost_user_write() return %d, create session failed", > - ret); > - return ret; > - } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_report("vhost_user_read() return %d, create session failed", > - ret); > - return ret; > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_report("vhost_user_write() return %d, create session failed", > + ret); > + return ret; > + } > + > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_report("vhost_user_read() return %d, create session failed", > + ret); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_CREATE_CRYPTO_SESSION) { > @@ -2648,6 +2715,7 @@ static int vhost_user_get_inflight_fd(struct vhost_dev *dev, > int fd; > int ret; > struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > CharBackend *chr = u->user->chr; > VhostUserMsg msg = { > .hdr.request = VHOST_USER_GET_INFLIGHT_FD, > @@ -2662,14 +2730,16 @@ static int vhost_user_get_inflight_fd(struct vhost_dev *dev, > return 0; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_GET_INFLIGHT_FD) { > @@ -2757,6 +2827,7 @@ bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp) > user->memory_slots = 0; > user->notifiers = g_ptr_array_new_full(VIRTIO_QUEUE_MAX / 4, > &vhost_user_state_destroy); > + qemu_mutex_init(&user->vhost_user_rw_lock); > return true; > } > > @@ -2769,6 +2840,7 @@ void vhost_user_cleanup(VhostUserState *user) > user->notifiers = (GPtrArray *) g_ptr_array_free(user->notifiers, true); > memory_region_transaction_commit(); > user->chr = NULL; > + qemu_mutex_destroy(&user->vhost_user_rw_lock); > } > > > @@ -2882,6 +2954,7 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, > { > int ret; > struct vhost_user *vu = dev->opaque; > + struct VhostUserState *us = vu->user; > VhostUserMsg msg = { > .hdr = { > .request = VHOST_USER_SET_DEVICE_STATE_FD, > @@ -2902,19 +2975,21 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, > return -ENOTSUP; > } > > - ret = vhost_user_write(dev, &msg, &fd, 1); > - close(fd); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to send SET_DEVICE_STATE_FD message"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, &fd, 1); > + close(fd); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to send SET_DEVICE_STATE_FD message"); > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to receive SET_DEVICE_STATE_FD reply"); > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to receive SET_DEVICE_STATE_FD reply"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_SET_DEVICE_STATE_FD) { > @@ -2951,6 +3026,8 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, > > static int vhost_user_check_device_state(struct vhost_dev *dev, Error **errp) > { > + struct vhost_user *u = dev->opaque; > + struct VhostUserState *us = u->user; > int ret; > VhostUserMsg msg = { > .hdr = { > @@ -2965,18 +3042,20 @@ static int vhost_user_check_device_state(struct vhost_dev *dev, Error **errp) > return -ENOTSUP; > } > > - ret = vhost_user_write(dev, &msg, NULL, 0); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to send CHECK_DEVICE_STATE message"); > - return ret; > - } > + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { > + ret = vhost_user_write(dev, &msg, NULL, 0); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to send CHECK_DEVICE_STATE message"); > + return ret; > + } > > - ret = vhost_user_read(dev, &msg); > - if (ret < 0) { > - error_setg_errno(errp, -ret, > - "Failed to receive CHECK_DEVICE_STATE reply"); > - return ret; > + ret = vhost_user_read(dev, &msg); > + if (ret < 0) { > + error_setg_errno(errp, -ret, > + "Failed to receive CHECK_DEVICE_STATE reply"); > + return ret; > + } > } > > if (msg.hdr.request != VHOST_USER_CHECK_DEVICE_STATE) { > diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h > index 324cd8663a..387ab6da2e 100644 > --- a/include/hw/virtio/vhost-user.h > +++ b/include/hw/virtio/vhost-user.h > @@ -67,6 +67,9 @@ typedef struct VhostUserState { > GPtrArray *notifiers; > int memory_slots; > bool supports_config; > + > + /* Hold lock for vhost_user_write/read cycle */ > + QemuMutex vhost_user_rw_lock; > } VhostUserState; So it's not a rw lock. It's just a mutex. Lock should be named after what they protect, not after where they are held. In this case, this ensures only 1 request is outstanding at a time. So vhost_user_request_reply_lock > > /** > -- > 2.45.2
On Sun, 21 Jul 2024 at 01:11, Michael S. Tsirkin <mst@redhat.com> wrote: > So it's not a rw lock. It's just a mutex. > Lock should be named after what they protect, not > after where they are held. > In this case, this ensures only 1 request is > outstanding at a time. > So vhost_user_request_reply_lock Okay, will do this change. Thank you. --- - Prasad
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 00561daa06..99881c487f 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -24,6 +24,7 @@ #include "qemu/main-loop.h" #include "qemu/uuid.h" #include "qemu/sockets.h" +#include "qemu/lockable.h" #include "sysemu/runstate.h" #include "sysemu/cryptodev.h" #include "migration/postcopy-ram.h" @@ -433,6 +434,8 @@ int vhost_user_gpu_set_socket(struct vhost_dev *dev, int fd) static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, struct vhost_log *log) { + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; int fds[VHOST_USER_MAX_RAM_SLOTS]; size_t fd_num = 0; bool shmfd = virtio_has_feature(dev->protocol_features, @@ -455,23 +458,25 @@ static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, fds[fd_num++] = log->fd; } - ret = vhost_user_write(dev, &msg, fds, fd_num); - if (ret < 0) { - return ret; - } - - if (shmfd) { - msg.hdr.size = 0; - ret = vhost_user_read(dev, &msg); + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, fds, fd_num); if (ret < 0) { return ret; } - if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) { - error_report("Received unexpected msg type. " - "Expected %d received %d", - VHOST_USER_SET_LOG_BASE, msg.hdr.request); - return -EPROTO; + if (shmfd) { + msg.hdr.size = 0; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + return ret; + } + + if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) { + error_report("Received unexpected msg type. " + "Expected %d received %d", + VHOST_USER_SET_LOG_BASE, msg.hdr.request); + return -EPROTO; + } } } @@ -664,6 +669,7 @@ static int send_remove_regions(struct vhost_dev *dev, bool reply_supported) { struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; struct vhost_memory_region *shadow_reg; int i, fd, shadow_reg_idx, ret; ram_addr_t offset; @@ -685,16 +691,18 @@ static int send_remove_regions(struct vhost_dev *dev, vhost_user_fill_msg_region(®ion_buffer, shadow_reg, 0); msg->payload.mem_reg.region = region_buffer; - ret = vhost_user_write(dev, msg, NULL, 0); - if (ret < 0) { - return ret; - } - - if (reply_supported) { - ret = process_message_reply(dev, msg); - if (ret) { + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, msg, NULL, 0); + if (ret < 0) { return ret; } + + if (reply_supported) { + ret = process_message_reply(dev, msg); + if (ret) { + return ret; + } + } } } @@ -725,6 +733,9 @@ static int send_add_regions(struct vhost_dev *dev, VhostUserMsg msg_reply; VhostUserMemoryRegion region_buffer; + struct VhostUserState *us = u->user; + QEMU_LOCK_GUARD(&us->vhost_user_rw_lock); + for (i = 0; i < nr_add_reg; i++) { reg = add_reg[i].region; reg_idx = add_reg[i].reg_idx; @@ -893,6 +904,7 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, bool config_mem_slots) { struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; int fds[VHOST_MEMORY_BASELINE_NREGIONS]; size_t fd_num = 0; VhostUserMsg msg_reply; @@ -926,14 +938,16 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, return ret; } - ret = vhost_user_write(dev, &msg, fds, fd_num); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, fds, fd_num); + if (ret < 0) { + return ret; + } - ret = vhost_user_read(dev, &msg_reply); - if (ret < 0) { - return ret; + ret = vhost_user_read(dev, &msg_reply); + if (ret < 0) { + return ret; + } } if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) { @@ -1005,6 +1019,7 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, struct vhost_memory *mem) { struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; int fds[VHOST_MEMORY_BASELINE_NREGIONS]; size_t fd_num = 0; bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler; @@ -1044,13 +1059,15 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, return ret; } - ret = vhost_user_write(dev, &msg, fds, fd_num); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, fds, fd_num); + if (ret < 0) { + return ret; + } - if (reply_supported) { - return process_message_reply(dev, &msg); + if (reply_supported) { + return process_message_reply(dev, &msg); + } } } @@ -1080,6 +1097,8 @@ static int vhost_user_set_vring_endian(struct vhost_dev *dev, static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) { int ret; + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; VhostUserMsg msg = { .hdr.request = request, .hdr.flags = VHOST_USER_VERSION, @@ -1089,14 +1108,16 @@ static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) return 0; } - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + return ret; + } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - return ret; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + return ret; + } } if (msg.hdr.request != request) { @@ -1129,6 +1150,8 @@ static int vhost_user_write_sync(struct vhost_dev *dev, VhostUserMsg *msg, bool wait_for_reply) { int ret; + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; if (wait_for_reply) { bool reply_supported = virtio_has_feature(dev->protocol_features, @@ -1138,25 +1161,27 @@ static int vhost_user_write_sync(struct vhost_dev *dev, VhostUserMsg *msg, } } - ret = vhost_user_write(dev, msg, NULL, 0); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, msg, NULL, 0); + if (ret < 0) { + return ret; + } - if (wait_for_reply) { - uint64_t dummy; + if (wait_for_reply) { + uint64_t dummy; - if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) { - return process_message_reply(dev, msg); - } + if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) { + return process_message_reply(dev, msg); + } - /* - * We need to wait for a reply but the backend does not - * support replies for the command we just sent. - * Send VHOST_USER_GET_FEATURES which makes all backends - * send a reply. - */ - return vhost_user_get_features(dev, &dummy); + /* + * We need to wait for a reply but the backend does not + * support replies for the command we just sent. + * Send VHOST_USER_GET_FEATURES which makes all backends + * send a reply. + */ + return vhost_user_get_features(dev, &dummy); + } } return 0; @@ -1277,20 +1302,23 @@ static int vhost_user_get_vring_base(struct vhost_dev *dev, .hdr.size = sizeof(msg.payload.state), }; struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; VhostUserHostNotifier *n = fetch_notifier(u->user, ring->index); if (n) { vhost_user_host_notifier_remove(n, dev->vdev); } - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + return ret; + } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - return ret; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + return ret; + } } if (msg.hdr.request != VHOST_USER_GET_VRING_BASE) { @@ -1661,6 +1689,7 @@ int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid, int *dmabuf_fd) { struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; CharBackend *chr = u->user->chr; int ret; VhostUserMsg msg = { @@ -1669,14 +1698,16 @@ int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid, }; memcpy(msg.payload.object.uuid, uuid, sizeof(msg.payload.object.uuid)); - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + return ret; + } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - return ret; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + return ret; + } } if (msg.hdr.request != VHOST_USER_GET_SHARED_OBJECT) { @@ -1858,6 +1889,7 @@ static int vhost_setup_backend_channel(struct vhost_dev *dev) .hdr.flags = VHOST_USER_VERSION, }; struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; int sv[2], ret = 0; bool reply_supported = virtio_has_feature(dev->protocol_features, VHOST_USER_PROTOCOL_F_REPLY_ACK); @@ -1889,15 +1921,16 @@ static int vhost_setup_backend_channel(struct vhost_dev *dev) msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; } - ret = vhost_user_write(dev, &msg, &sv[1], 1); - if (ret) { - goto out; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, &sv[1], 1); + if (ret) { + goto out; + } - if (reply_supported) { - ret = process_message_reply(dev, &msg); + if (reply_supported) { + ret = process_message_reply(dev, &msg); + } } - out: close(sv[1]); if (ret) { @@ -1985,6 +2018,7 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp) { #ifdef CONFIG_LINUX struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; CharBackend *chr = u->user->chr; int ufd; int ret; @@ -1993,16 +2027,18 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp) .hdr.flags = VHOST_USER_VERSION, }; - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - error_setg(errp, "Failed to send postcopy_advise to vhost"); - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + error_setg(errp, "Failed to send postcopy_advise to vhost"); + return ret; + } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - error_setg(errp, "Failed to get postcopy_advise reply from vhost"); - return ret; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + error_setg(errp, "Failed to get postcopy_advise reply from vhost"); + return ret; + } } if (msg.hdr.request != VHOST_USER_POSTCOPY_ADVISE) { @@ -2051,16 +2087,19 @@ static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp) trace_vhost_user_postcopy_listen(); - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - error_setg(errp, "Failed to send postcopy_listen to vhost"); - return ret; - } + struct VhostUserState *us = u->user; + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + error_setg(errp, "Failed to send postcopy_listen to vhost"); + return ret; + } - ret = process_message_reply(dev, &msg); - if (ret) { - error_setg(errp, "Failed to receive reply to postcopy_listen"); - return ret; + ret = process_message_reply(dev, &msg); + if (ret) { + error_setg(errp, "Failed to receive reply to postcopy_listen"); + return ret; + } } return 0; @@ -2077,19 +2116,22 @@ static int vhost_user_postcopy_end(struct vhost_dev *dev, Error **errp) }; int ret; struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; trace_vhost_user_postcopy_end_entry(); - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - error_setg(errp, "Failed to send postcopy_end to vhost"); - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + error_setg(errp, "Failed to send postcopy_end to vhost"); + return ret; + } - ret = process_message_reply(dev, &msg); - if (ret) { - error_setg(errp, "Failed to receive reply to postcopy_end"); - return ret; + ret = process_message_reply(dev, &msg); + if (ret) { + error_setg(errp, "Failed to receive reply to postcopy_end"); + return ret; + } } postcopy_unregister_shared_ufd(&u->postcopy_fd); close(u->postcopy_fd.fd); @@ -2359,6 +2401,8 @@ static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu) bool reply_supported = virtio_has_feature(dev->protocol_features, VHOST_USER_PROTOCOL_F_REPLY_ACK); int ret; + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_NET_MTU))) { return 0; @@ -2372,14 +2416,16 @@ static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu) msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; } - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + return ret; + } - /* If reply_ack supported, backend has to ack specified MTU is valid */ - if (reply_supported) { - return process_message_reply(dev, &msg); + /* If reply_ack supported, backend has to ack specified MTU is valid */ + if (reply_supported) { + return process_message_reply(dev, &msg); + } } return 0; @@ -2396,12 +2442,19 @@ static int vhost_user_send_device_iotlb_msg(struct vhost_dev *dev, .payload.iotlb = *imsg, }; - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - return ret; + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; + + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + return ret; + } + + ret = process_message_reply(dev, &msg); } - return process_message_reply(dev, &msg); + return ret; } @@ -2414,6 +2467,8 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, uint32_t config_len, Error **errp) { int ret; + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; VhostUserMsg msg = { .hdr.request = VHOST_USER_GET_CONFIG, .hdr.flags = VHOST_USER_VERSION, @@ -2430,16 +2485,19 @@ static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, msg.payload.config.offset = 0; msg.payload.config.size = config_len; - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - error_setg_errno(errp, -ret, "vhost_get_config failed"); - return ret; - } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - error_setg_errno(errp, -ret, "vhost_get_config failed"); - return ret; + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + error_setg_errno(errp, -ret, "vhost_get_config failed"); + return ret; + } + + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + error_setg_errno(errp, -ret, "vhost_get_config failed"); + return ret; + } } if (msg.hdr.request != VHOST_USER_GET_CONFIG) { @@ -2464,6 +2522,8 @@ static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, { int ret; uint8_t *p; + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; bool reply_supported = virtio_has_feature(dev->protocol_features, VHOST_USER_PROTOCOL_F_REPLY_ACK); @@ -2492,13 +2552,15 @@ static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, p = msg.payload.config.region; memcpy(p, data, size); - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + return ret; + } - if (reply_supported) { - return process_message_reply(dev, &msg); + if (reply_supported) { + return process_message_reply(dev, &msg); + } } return 0; @@ -2509,6 +2571,8 @@ static int vhost_user_crypto_create_session(struct vhost_dev *dev, uint64_t *session_id) { int ret; + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; bool crypto_session = virtio_has_feature(dev->protocol_features, VHOST_USER_PROTOCOL_F_CRYPTO_SESSION); CryptoDevBackendSessionInfo *backend_info = session_info; @@ -2572,18 +2636,21 @@ static int vhost_user_crypto_create_session(struct vhost_dev *dev, msg.payload.session.op_code = backend_info->op_code; msg.payload.session.session_id = backend_info->session_id; - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - error_report("vhost_user_write() return %d, create session failed", - ret); - return ret; - } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - error_report("vhost_user_read() return %d, create session failed", - ret); - return ret; + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + error_report("vhost_user_write() return %d, create session failed", + ret); + return ret; + } + + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + error_report("vhost_user_read() return %d, create session failed", + ret); + return ret; + } } if (msg.hdr.request != VHOST_USER_CREATE_CRYPTO_SESSION) { @@ -2648,6 +2715,7 @@ static int vhost_user_get_inflight_fd(struct vhost_dev *dev, int fd; int ret; struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; CharBackend *chr = u->user->chr; VhostUserMsg msg = { .hdr.request = VHOST_USER_GET_INFLIGHT_FD, @@ -2662,14 +2730,16 @@ static int vhost_user_get_inflight_fd(struct vhost_dev *dev, return 0; } - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + return ret; + } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - return ret; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + return ret; + } } if (msg.hdr.request != VHOST_USER_GET_INFLIGHT_FD) { @@ -2757,6 +2827,7 @@ bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp) user->memory_slots = 0; user->notifiers = g_ptr_array_new_full(VIRTIO_QUEUE_MAX / 4, &vhost_user_state_destroy); + qemu_mutex_init(&user->vhost_user_rw_lock); return true; } @@ -2769,6 +2840,7 @@ void vhost_user_cleanup(VhostUserState *user) user->notifiers = (GPtrArray *) g_ptr_array_free(user->notifiers, true); memory_region_transaction_commit(); user->chr = NULL; + qemu_mutex_destroy(&user->vhost_user_rw_lock); } @@ -2882,6 +2954,7 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, { int ret; struct vhost_user *vu = dev->opaque; + struct VhostUserState *us = vu->user; VhostUserMsg msg = { .hdr = { .request = VHOST_USER_SET_DEVICE_STATE_FD, @@ -2902,19 +2975,21 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, return -ENOTSUP; } - ret = vhost_user_write(dev, &msg, &fd, 1); - close(fd); - if (ret < 0) { - error_setg_errno(errp, -ret, - "Failed to send SET_DEVICE_STATE_FD message"); - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, &fd, 1); + close(fd); + if (ret < 0) { + error_setg_errno(errp, -ret, + "Failed to send SET_DEVICE_STATE_FD message"); + return ret; + } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - error_setg_errno(errp, -ret, - "Failed to receive SET_DEVICE_STATE_FD reply"); - return ret; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + error_setg_errno(errp, -ret, + "Failed to receive SET_DEVICE_STATE_FD reply"); + return ret; + } } if (msg.hdr.request != VHOST_USER_SET_DEVICE_STATE_FD) { @@ -2951,6 +3026,8 @@ static int vhost_user_set_device_state_fd(struct vhost_dev *dev, static int vhost_user_check_device_state(struct vhost_dev *dev, Error **errp) { + struct vhost_user *u = dev->opaque; + struct VhostUserState *us = u->user; int ret; VhostUserMsg msg = { .hdr = { @@ -2965,18 +3042,20 @@ static int vhost_user_check_device_state(struct vhost_dev *dev, Error **errp) return -ENOTSUP; } - ret = vhost_user_write(dev, &msg, NULL, 0); - if (ret < 0) { - error_setg_errno(errp, -ret, - "Failed to send CHECK_DEVICE_STATE message"); - return ret; - } + WITH_QEMU_LOCK_GUARD(&us->vhost_user_rw_lock) { + ret = vhost_user_write(dev, &msg, NULL, 0); + if (ret < 0) { + error_setg_errno(errp, -ret, + "Failed to send CHECK_DEVICE_STATE message"); + return ret; + } - ret = vhost_user_read(dev, &msg); - if (ret < 0) { - error_setg_errno(errp, -ret, - "Failed to receive CHECK_DEVICE_STATE reply"); - return ret; + ret = vhost_user_read(dev, &msg); + if (ret < 0) { + error_setg_errno(errp, -ret, + "Failed to receive CHECK_DEVICE_STATE reply"); + return ret; + } } if (msg.hdr.request != VHOST_USER_CHECK_DEVICE_STATE) { diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h index 324cd8663a..387ab6da2e 100644 --- a/include/hw/virtio/vhost-user.h +++ b/include/hw/virtio/vhost-user.h @@ -67,6 +67,9 @@ typedef struct VhostUserState { GPtrArray *notifiers; int memory_slots; bool supports_config; + + /* Hold lock for vhost_user_write/read cycle */ + QemuMutex vhost_user_rw_lock; } VhostUserState; /**