Stefano Garzarella 3fe356d58e vsock/virtio: discard packets only when socket is really closed ... Starting from commit 8692cefc43 ("virtio_vsock: Fix race condition in virtio_transport_recv_pkt"), we discard packets in virtio_transport_recv_pkt() if the socket has been released. When the socket is connected, we schedule a delayed work to wait the RST packet from the other peer, also if SHUTDOWN_MASK is set in sk->sk_shutdown. This is done to complete the virtio-vsock shutdown algorithm, releasing the port assigned to the socket definitively only when the other peer has consumed all the packets. If we discard the RST packet received, the socket will be closed only when the VSOCK_CLOSE_TIMEOUT is reached. Sergio discovered the issue while running ab(1) HTTP benchmark using libkrun [1] and observing a latency increase with that commit. To avoid this issue, we discard packet only if the socket is really closed (SOCK_DONE flag is set). We also set SOCK_DONE in virtio_transport_release() when we don't need to wait any packets from the other peer (we didn't schedule the delayed work). In this case we remove the socket from the vsock lists, releasing the port assigned. [1] https://github.com/containers/libkrun Fixes: 8692cefc43 ("virtio_vsock: Fix race condition in virtio_transport_recv_pkt") Cc: justin.he@arm.com Reported-by: Sergio Lopez <slp@redhat.com> Tested-by: Sergio Lopez <slp@redhat.com> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Acked-by: Jia He <justin.he@arm.com> Link: https://lore.kernel.org/r/20201120104736.73749-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>		2020-11-23 16:36:29 -08:00
..
af_vsock.c	vsock: forward all packets to the host when no H2G is registered	2020-11-14 11:33:39 -08:00
af_vsock_tap.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
diag.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321	2019-06-05 17:37:05 +02:00
hyperv_transport.c	vsock: fix potential deadlock in transport->release()	2020-02-27 12:03:56 -08:00
Kconfig	vsock: add vsock_loopback transport	2019-12-11 15:01:23 -08:00
Makefile	vsock: add vsock_loopback transport	2019-12-11 15:01:23 -08:00
virtio_transport.c	vsock/virtio: annotate 'the_virtio_vsock' RCU pointer	2020-07-15 17:47:15 -07:00
virtio_transport_common.c	vsock/virtio: discard packets only when socket is really closed	2020-11-23 16:36:29 -08:00
vmci_transport.c	vsock/vmci: make vmci_vsock_transport_cb() static	2020-06-05 13:18:26 -07:00
vmci_transport.h	vsock: handle buffer_size sockopts in the core	2019-11-14 18:12:18 -08:00
vmci_transport_notify.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321	2019-06-05 17:37:05 +02:00
vmci_transport_notify.h	vsock: remove include/linux/vm_sockets.h file	2019-11-14 18:12:17 -08:00
vmci_transport_notify_qstate.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321	2019-06-05 17:37:05 +02:00
vsock_addr.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321	2019-06-05 17:37:05 +02:00
vsock_loopback.c	vsock: add vsock_loopback transport	2019-12-11 15:01:23 -08:00