fb_deferred_io_work() can access the vmbus ringbuffer by calling
fbdefio->deferred_io() -> synthvid_deferred_io() -> synthvid_update().
Because the vmbus ringbuffer is inaccessible between hvfb_suspend()
and hvfb_resume(), we must cancel info->deferred_work before calling
vmbus_close() and then reschedule it after we reopen the channel
in hvfb_resume().
Fixes: a4ddb11d297e ("video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver")
Fixes: 824946a8b6fb ("video: hyperv_fb: Add the support of hibernation")
Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
Reviewed-by: Wei Hu <weh@xxxxxxxxxxxxx>
---
This is a RESEND of https://lkml.org/lkml/2019/11/20/73 .
The only change is the addition of Wei's Review-ed-by.
Please review.
If it looks good, Sasha Levin, can you please pick it up via the
hyperv/linux.git tree, as you did last time for this driver?
drivers/video/fbdev/hyperv_fb.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index 4cd27e5172a1..08bc0dfb5ce7 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -1194,6 +1194,7 @@ static int hvfb_suspend(struct hv_device *hdev)
fb_set_suspend(info, 1);
cancel_delayed_work_sync(&par->dwork);
+ cancel_delayed_work_sync(&info->deferred_work);
par->update_saved = par->update;
par->update = false;
@@ -1227,6 +1228,7 @@ static int hvfb_resume(struct hv_device *hdev)
par->fb_ready = true;
par->update = par->update_saved;
+ schedule_delayed_work(&info->deferred_work, info->fbdefio->delay);
schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
/* 0 means do resume */
--
2.19.1
