Hello, Parthasarathy.
I have a question regarding commit 6f00089c7372ba97 ("tipc: remove
SS_DISCONNECTING state").
That commit added
sk->sk_shutdown = SEND_SHUTDOWN;
into tipc_shutdown(). What is the reason you chose SEND_SHUTDOWN despite how ==
SHUT_RDWR ?
Since Wouter commented that NBD expects SOCK_STREAM sockets, I think that
passing TIPC's
stream socket is legal. And I can trigger hung task warning using a reproducer
shown below.
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#include <fcntl.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <linux/nbd.h>
#include <unistd.h>
int main(int argc, char *argv[])
{
const int fd = open("/dev/nbd0", 3);
int fds[2] = { -1, -1 };
alarm(5);
socketpair(PF_TIPC, SOCK_STREAM, 0, fds);
ioctl(fd, NBD_SET_SOCK, fds[0]);
ioctl(fd, NBD_DO_IT, 0); /* To be interrupted by SIGALRM. */
return 0;
}
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Applying a patch shown below solves the hung task warning, but I can't evaluate
the side effect of this patch, for I don't know why you chose SEND_SHUTDOWN and
how TIPC socket works. Can we apply this patch?
----------
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -2771,10 +2771,7 @@ static int tipc_shutdown(struct socket *sock, int how)
trace_tipc_sk_shutdown(sk, NULL, TIPC_DUMP_ALL, " ");
__tipc_shutdown(sock, TIPC_CONN_SHUTDOWN);
- if (tipc_sk_type_connectionless(sk))
- sk->sk_shutdown = SHUTDOWN_MASK;
- else
- sk->sk_shutdown = SEND_SHUTDOWN;
+ sk->sk_shutdown = SHUTDOWN_MASK;
if (sk->sk_state == TIPC_DISCONNECTING) {
/* Discard any unreceived messages */
----------
