Hello, this patchset evolved from previous v2 version (see link below). It does several updates to virtio/vsock: 1) Changes 'virtio_transport_inc/dec_rx_pkt()' interface. Now instead of using skbuff state ('head' and 'data' pointers) to update 'fwd_cnt' and 'rx_bytes', integer value is passed as an input argument. This makes code more simple, because in this case we don't need to update skbuff state before calling 'virtio_transport_inc/dec_rx_pkt()'. In more common words - we don't need to change skbuff state to update 'rx_bytes' and 'fwd_cnt' correctly. 2) For SOCK_STREAM, when copying data to user fails, current skbuff is not dropped. Next read attempt will use same skbuff and last offset. Instead of 'skb_dequeue()', 'skb_peek()' + '__skb_unlink()' are used. This behaviour was implemented before skbuff support. 3) For SOCK_SEQPACKET it removes unneeded 'skb_pull()' call, because for this type of socket each skbuff is used only once: after removing it from socket's queue, it will be freed anyway. Test for 2) also added: Test tries to 'recv()' data to NULL buffer, then does 'recv()' with valid buffer. For SOCK_STREAM second 'recv()' must return data, because skbuff must not be dropped, but for SOCK_SEQPACKET skbuff will be dropped by kernel, and 'recv()' will return EAGAIN. Link to v1 on lore: https://lore.kernel.org/netdev/c2d3e204-89d9-88e9-8a15-3fe027e56b4b@xxxxxxxxxxxxxx/ Link to v2 on lore: https://lore.kernel.org/netdev/a7ab414b-5e41-c7b6-250b-e8401f335859@xxxxxxxxxxxxxx/ Link to v3 on lore: https://lore.kernel.org/netdev/0abeec42-a11d-3a51-453b-6acf76604f2e@xxxxxxxxxxxxxx/ Change log: v1 -> v2: - For SOCK_SEQPACKET call 'skb_pull()' also in case of copy failure or dropping skbuff (when we just waiting message end). - Handle copy failure for SOCK_STREAM in the same manner (plus free current skbuff). - Replace bug repdroducer with new test in vsock_test.c v2 -> v3: - Replace patch which removes 'skb->len' subtraction from function 'virtio_transport_dec_rx_pkt()' with patch which updates functions 'virtio_transport_inc/dec_rx_pkt()' by passing integer argument instead of skbuff pointer. - Replace patch which drops skbuff when copying to user fails with patch which changes this behaviour by keeping skbuff in queue until it has no data. - Add patch for SOCK_SEQPACKET which removes redundant 'skb_pull()' call on read. - I remove "Fixes" tag from all patches, because all of them now change code logic, not only fix something. v3 -> v4: - Update commit messages in all patches except test. - Add "Fixes" tag to all patches except test. Arseniy Krasnov (4): virtio/vsock: don't use skbuff state to account credit virtio/vsock: remove redundant 'skb_pull()' call virtio/vsock: don't drop skbuff on copy failure test/vsock: copy to user failure test net/vmw_vsock/virtio_transport_common.c | 29 +++--- tools/testing/vsock/vsock_test.c | 118 ++++++++++++++++++++++++ 2 files changed, 131 insertions(+), 16 deletions(-) -- 2.25.1