net/9p: Switch to wait_event_killable()

commit 9523feac272ccad2ad8186ba4fcc89103754de52 upstream.

Because userspace gets Very Unhappy when calls like stat() and execve()
return -EINTR on 9p filesystem mounts. For instance, when bash is
looking in PATH for things to execute and some SIGCHLD interrupts
stat(), bash can throw a spurious 'command not found' since it doesn't
retry the stat().

In practice, hitting the problem is rare and needs a really
slow/bogged down 9p server.

Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/9p/client.c b/net/9p/client.c
index d43baabfb02db166b954cba36a3e1850810ffe4c..f24b774d221565132ac7a0d117397800e0c60209 100644 (file)
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -753,8 +753,7 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
        }
 again:
        /* Wait for the response */
-       err = wait_event_interruptible(*req->wq,
-                                      req->status >= REQ_STATUS_RCVD);
+       err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
 
        /*
         * Make sure our req is coherent with regard to updates in other

diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index daa749c8b3fbea2cc319ceb6a1ce4a9c20d9eece..071ac5c495fc450b78714e543f14743cc98386dd 100644 (file)
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -292,8 +292,8 @@ req_retry:
                if (err == -ENOSPC) {
                        chan->ring_bufs_avail = 0;
                        spin_unlock_irqrestore(&chan->lock, flags);
-                       err = wait_event_interruptible(*chan->vc_wq,
-                                                       chan->ring_bufs_avail);
+                       err = wait_event_killable(*chan->vc_wq,
+                                                 chan->ring_bufs_avail);
                        if (err  == -ERESTARTSYS)
                                return err;
 
@@ -324,7 +324,7 @@ static int p9_get_mapped_pages(struct virtio_chan *chan,
                 * Other zc request to finish here
                 */
                if (atomic_read(&vp_pinned) >= chan->p9_max_pages) {
-                       err = wait_event_interruptible(vp_wq,
+                       err = wait_event_killable(vp_wq,
                              (atomic_read(&vp_pinned) < chan->p9_max_pages));
                        if (err == -ERESTARTSYS)
                                return err;
@@ -454,8 +454,8 @@ req_retry_pinned:
                if (err == -ENOSPC) {
                        chan->ring_bufs_avail = 0;
                        spin_unlock_irqrestore(&chan->lock, flags);
-                       err = wait_event_interruptible(*chan->vc_wq,
-                                                      chan->ring_bufs_avail);
+                       err = wait_event_killable(*chan->vc_wq,
+                                                 chan->ring_bufs_avail);
                        if (err  == -ERESTARTSYS)
                                goto err_out;
 
@@ -472,8 +472,7 @@ req_retry_pinned:
        virtqueue_kick(chan->vq);
        spin_unlock_irqrestore(&chan->lock, flags);
        p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n");
-       err = wait_event_interruptible(*req->wq,
-                                      req->status >= REQ_STATUS_RCVD);
+       err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
        /*
         * Non kernel buffers are pinned, unpin them
         */