Re: [Intel-gfx] [PATCH 5/5] drm/i915: Kick out vga console

From: Ed Tomlinson
Date: Mon Jul 07 2014 - 06:45:58 EST


Daniel,

I am not quite sure I understand what you want me to test?
Do you want me to try it without:

> > + if (ret == 0) {
> > + ret = do_unregister_con_driver(&vga_con);

Thanks
Ed


On Monday 07 July 2014 10:48:26 Daniel Vetter wrote:
> On Mon, Jun 30, 2014 at 07:59:55AM +0100, Chris Wilson wrote:
> > On Sat, Jun 28, 2014 at 11:55:19PM -0400, Ed Tomlinson wrote:
> > > On Saturday 28 June 2014 15:28:22 Ed Tomlinson wrote:
> > >
> > > Resend without html krud which causes list to bounce the message.
> > >
> > > > Hi
> > > >
> > > > This commit ( a4de05268e674e8ed31df6348269e22d6c6a1803 ) hangs my boot with 3.16-git. Reverting it lets the boot proceed.
> > > >
> > > > I have an i7 with a built-in i915 and an pcie r7 260x. The R7 is the primary console. The i915 is initialized
> > > > but does not have a physical display attached.
> > > >
> > > > With the patch applied the boot stops at the messages:
> > > >
> > > > [drm] Memory usable by graphics device = 2048M
> > > > [drm] Replacing VGA console driver
> >
> > The issue looks like that we are ripping out the radeon fb_con whilst it
> > is active and that upsets everyone. In which case, I think the
> > compromise is:
> >
> >
> > diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> > index 5f44581..4915f1d 100644
> > --- a/drivers/gpu/drm/i915/i915_dma.c
> > +++ b/drivers/gpu/drm/i915/i915_dma.c
> > @@ -1439,18 +1439,20 @@ static int i915_kick_out_vgacon(struct drm_i915_private *dev_priv)
> > #else
> > static int i915_kick_out_vgacon(struct drm_i915_private *dev_priv)
> > {
> > - int ret;
> > + int ret = 0;
> >
> > DRM_INFO("Replacing VGA console driver\n");
> >
> > console_lock();
> > - ret = do_take_over_console(&dummy_con, 0, MAX_NR_CONSOLES - 1, 1);
> > - if (ret == 0) {
> > - ret = do_unregister_con_driver(&vga_con);
> > -
> > - /* Ignore "already unregistered". */
> > - if (ret == -ENODEV)
> > - ret = 0;
> > + if (con_is_bound(&vga_con)) {
> > + ret = do_take_over_console(&dummy_con, 0, MAX_NR_CONSOLES - 1, 1);
> > + if (ret == 0) {
> > + ret = do_unregister_con_driver(&vga_con);
>
> Hm, we should only conditionalize the take_over_console - unregistering
> vga_con is kinda the point to make sure it's gone for real. Ed, can you
> please retest with the if (con_is_bound) check just for the
> do_take_over_console call?
>
> Still puzzled wtf is going on here since as David says this should be a
> no-op.
>
> Thanks, Daniel
> > +
> > + /* Ignore "already unregistered". */
> > + if (ret == -ENODEV)
> > + ret = 0;
> > + }
> > }
> > console_unlock();
> >
> > -Chris
> >
>
>

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