Messages in this thread | | | Date | Wed, 20 Feb 2013 17:12:42 -0800 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH v2] vt: add init_hide parameter to suppress boot output |
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On Wed, Feb 20, 2013 at 02:08:25PM -0800, Andy Ross wrote: > On 02/20/2013 12:57 PM, Pavel Machek wrote: > >I'm sure something creative can be done with fake init that shuts > >the console up then execs previous init. No need to add more kernel > >knobs, I'd say. > > Fair enough, but some last words: > > That's argument is the "it's about logging" hypothesis again. Even if > it were possible to completely shut up console output (something > that's awfully hard in the general case when running on PC hardware, > and IMHO from a developer's perspective not even a good thing), that's > not the whole problem. The framebuffer console initialization does a > buffer clear and mode set, and that clobbers anything the bootloader > might have left on the screen prematurely, before userspace is ready > to throw up its own splash. Splash screens may be a silly > requirement, but they're still a requirement.
Yes, they are a requirement in some situations, and if you look most distros have already solved this issue for you, by not using a framebuffer at all. Why not just do the same thing in your Android system as you do have full control over the hardware and the boot process.
> And the suspend console problem is likewise at work: ideally you'd > like to know, for example, that the panel backlight is off before > suspending. But what happens in practice is that the kernel does a VT > switch to/from console 63 and the backlight wakes up (I'm not going to > pretend I have this bit completely figured out, but the problem is/was > real and this patch fixed it by suppressing the console visibility).
My systems don't drop down to the framebuffer when suspending, I think you need to look at using a better distro :)
> Now, the point that an in-kernel console is "going away" and thus not > worth augmenting with new APIs is valid. And this is a small patch > that's unlikely to be difficult to maintain in a custom tree. And as > we all agree there are other mechanisms that can be used here (even if > AFAICT they don't completely solve the problem), and indeed I'd love > to get surfaceflinger working with VT_ACTIVATE et. al. if I get a > chance. So I'm not going to cry if this isn't worth mainline.
I don't see why this is even needed for surfaceflinger systems, as again, you have full control over the hardware and system so you don't even need a framebuffer console at all.
thanks,
greg k-h
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