resending as it seems to have been corrupted on LKML!
The RPC client marks the socket closed. and the linger timeout is
cancelled. At this point, sk_shutdown should be set to zero, correct?
I don't see an xs_error_report() call here, which would confirm that the
socket took a trip through tcp_disconnect().
From my reading of tcp_disconnect(), it calls sk->sk_error_report(sk)
unconditionally so as there's no xs_error_report(), that surely means
the exact opposite: tcp_disconnect() wasn't called. If it's not
called, sk_shutdown is not cleared. And my revised tracing confirmed
that it was set to SEND_SHUTDOWN.