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 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel