virt: vbox: Do not use wait_event_interruptible when called from kernel context

Do not use wait_event_interruptible when vbg_hgcm_call() gets called from
kernel-context, such as it being called by the vboxsf filesystem code.

This fixes some filesystem related system calls on shared folders
unexpectedly failing with -EINTR.

Fixes: 0532a1b0d045 ("virt: vbox: Implement passing requestor info to the host for VirtualBox 6.0.x")
Reported-by: Ludovic Pouzenc <bugreports@pouzenc.fr>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210121150754.147598-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/virt/vboxguest/vboxguest_utils.c b/drivers/virt/vboxguest/vboxguest_utils.c
index ea05af41ec69e95a705baf377ffd7f8c176351d6..8d195e3f83012363a0db7fabbe3a27b38fd06bb2 100644 (file)
--- a/drivers/virt/vboxguest/vboxguest_utils.c
+++ b/drivers/virt/vboxguest/vboxguest_utils.c
@@ -468,7 +468,7 @@ static int hgcm_cancel_call(struct vbg_dev *gdev, struct vmmdev_hgcm_call *call)
  *               Cancellation fun.
  */
 static int vbg_hgcm_do_call(struct vbg_dev *gdev, struct vmmdev_hgcm_call *call,
-                           u32 timeout_ms, bool *leak_it)
+                           u32 timeout_ms, bool interruptible, bool *leak_it)
 {
        int rc, cancel_rc, ret;
        long timeout;
@@ -495,10 +495,15 @@ static int vbg_hgcm_do_call(struct vbg_dev *gdev, struct vmmdev_hgcm_call *call,
        else
                timeout = msecs_to_jiffies(timeout_ms);
 
-       timeout = wait_event_interruptible_timeout(
-                                       gdev->hgcm_wq,
-                                       hgcm_req_done(gdev, &call->header),
-                                       timeout);
+       if (interruptible) {
+               timeout = wait_event_interruptible_timeout(gdev->hgcm_wq,
+                                                          hgcm_req_done(gdev, &call->header),
+                                                          timeout);
+       } else {
+               timeout = wait_event_timeout(gdev->hgcm_wq,
+                                            hgcm_req_done(gdev, &call->header),
+                                            timeout);
+       }
 
        /* timeout > 0 means hgcm_req_done has returned true, so success */
        if (timeout > 0)
@@ -631,7 +636,8 @@ int vbg_hgcm_call(struct vbg_dev *gdev, u32 requestor, u32 client_id,
        hgcm_call_init_call(call, client_id, function, parms, parm_count,
                            bounce_bufs);
 
-       ret = vbg_hgcm_do_call(gdev, call, timeout_ms, &leak_it);
+       ret = vbg_hgcm_do_call(gdev, call, timeout_ms,
+                              requestor & VMMDEV_REQUESTOR_USERMODE, &leak_it);
        if (ret == 0) {
                *vbox_status = call->header.result;
                ret = hgcm_call_copy_back_result(call, parms, parm_count,