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

From: Hans de Goede
Date: Wed Jan 20 2021 - 11:50:17 EST


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")
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/virt/vboxguest/vboxguest_utils.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/virt/vboxguest/vboxguest_utils.c b/drivers/virt/vboxguest/vboxguest_utils.c
index ea05af41ec69..8d195e3f8301 100644
--- 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,
--
2.28.0