Re: [RFC PATCH v3 5/9] vsock: pass sock_rcvlowat to notify_poll_in as target
From: Stefano Garzarella <sgarzare@redhat.com>
Date: 2022-08-08 10:46:50
Also in:
kvm, lkml, netdev, virtualization
On Wed, Aug 03, 2022 at 01:59:49PM +0000, Arseniy Krasnov wrote:
This callback controls setting of POLLIN,POLLRDNORM output bits of poll() syscall,but in some cases,it is incorrectly to set it, when socket has at least 1 bytes of available data.
I suggest you refrase the description a bit, which should describe what was the problem and what the patch does, so I was thinking something like this: Passing 1 as the target to notify_poll_in(), we don't honor what the user has set via SO_RCVLOWAT, going to set POLLIN and POLLRDNORM, even if we don't have the amount of bytes expected by the user. Let's use sock_rcvlowat() to get the right target to pass to notify_poll_in(). Anyway, the patch LGTM: Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
quoted hunk ↗ jump to hunk
Signed-off-by: Arseniy Krasnov <redacted> --- net/vmw_vsock/af_vsock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 016ad5ff78b7..3a1426eb8baa 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c@@ -1066,8 +1066,9 @@ static __poll_t vsock_poll(struct file *file, struct socket *sock,if (transport && transport->stream_is_active(vsk) && !(sk->sk_shutdown & RCV_SHUTDOWN)) { bool data_ready_now = false; + int target = sock_rcvlowat(sk, 0, INT_MAX); int ret = transport->notify_poll_in( - vsk, 1, &data_ready_now); + vsk, target, &data_ready_now); if (ret < 0) { mask |= EPOLLERR; } else { -- 2.25.1