Messages in this thread | | | Date | Tue, 24 Jun 2014 09:51:01 -0400 | From | Greg KH <> | Subject | Re: [PATCH] video: hyperv: hyperv_fb: refresh the VM screen by force on VM panic |
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On Tue, Jun 24, 2014 at 08:29:17AM +0800, Dexuan Cui wrote: > Currently the VSC has no chance to notify the VSP of the dirty rectangle on VM > panic because the notification work is done in a workqueue, and in panic() the > kernel typically ends up in an infinite loop, and a typical kernel config has > CONFIG_PREEMPT_VOLUNTARY=y and CONFIG_PREEMPT is not set, so a context switch > can't happen in panic() and the workqueue won't have a chance to run. As a > result, the VM Connection window can't refresh until it's closed and we > re-connect to the VM. > > We can register a handler on panic_notifier_list: the handler can notify > the VSC and switch the framebuffer driver to a "synchronous mode", meaning > the VSC flushes any future framebuffer change to the VSP immediately. > > MS-TFS: 157532
What is this line for?
thanks,
greg k-h
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