AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-11-24 14:41:02 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity

cifs: smbd: avoid reconnect lockup

Browse Source 
During transport reconnect, other processes may have registered memory
and blocked on transport. This creates a deadlock situation because the
transport resources can't be freed, and reconnect is blocked.

Fix this by returning to upper layer on timeout. Before returning,
transport status is set to reconnecting so other processes will release
memory registration resources.

Upper layer will retry the reconnect. This is not in fast I/O path so
setting the timeout to 5 seconds.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
This commit is contained in:
Long Li 2018-03-30 15:16:35 -07:00 committed by Steve French
parent 2a18287b54
commit 48f238a79f
1 changed files with 8 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
fs/cifs/smbdirect.c
View File

@ -1498,8 +1498,8 @@ int smbd_reconnect(struct TCP_Server_Info *server)
log_rdma_event(INFO, "reconnecting rdma session\n");
if (!server->smbd_conn) {
log_rdma_event(ERR, "rdma session already destroyed\n");
return -EINVAL;
log_rdma_event(INFO, "rdma session already destroyed\n");
goto create_conn;
}
/*
@ -1512,15 +1512,19 @@ int smbd_reconnect(struct TCP_Server_Info *server)
}
/* wait until the transport is destroyed */
wait_event(server->smbd_conn->wait_destroy,
server->smbd_conn->transport_status == SMBD_DESTROYED);
if (!wait_event_timeout(server->smbd_conn->wait_destroy,
server->smbd_conn->transport_status == SMBD_DESTROYED, 5*HZ))
return -EAGAIN;
destroy_workqueue(server->smbd_conn->workqueue);
kfree(server->smbd_conn);
create_conn:
log_rdma_event(INFO, "creating rdma session\n");
server->smbd_conn = smbd_get_connection(
server, (struct sockaddr *) &server->dstaddr);
log_rdma_event(INFO, "created rdma session info=%p\n",
server->smbd_conn);
return server->smbd_conn ? 0 : -ENOENT;
}