IB/ipath: Add locking for interrupt use of ipath_pd contexts vs free
Fixes timing race resulting in panic. Not a performance sensitive path.
Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index ceab52c..239d4e8 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -2046,7 +2046,9 @@
struct ipath_filedata *fd;
struct ipath_portdata *pd;
struct ipath_devdata *dd;
+ unsigned long flags;
unsigned port;
+ struct pid *pid;
ipath_cdbg(VERBOSE, "close on dev %lx, private data %p\n",
(long)in->i_rdev, fp->private_data);
@@ -2079,14 +2081,13 @@
mutex_unlock(&ipath_mutex);
goto bail;
}
+ /* early; no interrupt users after this */
+ spin_lock_irqsave(&dd->ipath_uctxt_lock, flags);
port = pd->port_port;
-
- if (pd->port_hdrqfull) {
- ipath_cdbg(PROC, "%s[%u] had %u rcvhdrqfull errors "
- "during run\n", pd->port_comm, pid_nr(pd->port_pid),
- pd->port_hdrqfull);
- pd->port_hdrqfull = 0;
- }
+ dd->ipath_pd[port] = NULL;
+ pid = pd->port_pid;
+ pd->port_pid = NULL;
+ spin_unlock_irqrestore(&dd->ipath_uctxt_lock, flags);
if (pd->port_rcvwait_to || pd->port_piowait_to
|| pd->port_rcvnowait || pd->port_pionowait) {
@@ -2143,13 +2144,11 @@
unlock_expected_tids(pd);
ipath_stats.sps_ports--;
ipath_cdbg(PROC, "%s[%u] closed port %u:%u\n",
- pd->port_comm, pid_nr(pd->port_pid),
+ pd->port_comm, pid_nr(pid),
dd->ipath_unit, port);
}
- put_pid(pd->port_pid);
- pd->port_pid = NULL;
- dd->ipath_pd[pd->port_port] = NULL; /* before releasing mutex */
+ put_pid(pid);
mutex_unlock(&ipath_mutex);
ipath_free_pddata(dd, pd); /* after releasing the mutex */