Re: Where is dumbcon_init() called?

[Zoltan B. <zb...@fr...>]

Zoltan Boszormenyi =EDrta:
>=20
> --- dummycon.c.old	2004-05-31 11:48:34.137610128 +0200
> +++ dummycon.c	2004-05-31 11:51:39.421442704 +0200
> @@ -103,16 +103,21 @@
>          const char *display_desc =3D NULL;
>          struct vt_struct *vt;
> =20
> +printk("%s() called\n", __FUNCTION__);
> +
>          vt =3D (struct vt_struct *) kmalloc(sizeof(struct vt_struct),G=
FP_KERNEL);
> =20
>          if (!vt) return -ENOMEM;
> =20
> +printk("%s() kmalloc successful\n", __FUNCTION__);
> +
>          memset(vt, 0, sizeof(struct vt_struct));
>          vt->vt_kmalloced =3D 1;
>          vt->vt_sw =3D &dummy_con;
>          display_desc =3D vt_map_display(vt, 1, MIN_NR_CONSOLES);
>          if (!display_desc) {
>  		kfree(vt);
> +printk("%s() vt_map_display() failed\n", __FUNCTION__);
>  	        return -ENODEV;
>  	}
>  	printk("Console: mono %s %dx%d vc:%d-%d\n", display_desc,
>=20

OK, running

make clean
make
make install
modprobe dumdum

after putting these into the tree's drivers/video/console/dummycon.c,
I got this:

dumdum: module license 'unspecified' taints kernel.
dumbcon_add() called
dumbcon_add() kmalloc successful
invalid operand: 0000 [1]
CPU 0
Modules linked in: dumdum snd_emu10k1 snd_util_mem snd_hwdep
...

I don't quote it entirely again, seems like a NULL pointer deref.
Next round of changes attached.

# modprobe dumdum
# dmesg
...
dumdum: module license 'unspecified' taints kernel.
dumbcon_add() called
dumbcon_add() kmalloc successful
vt_map_display() called
vt_map_display() before ->con_startup()
vt_map_display() after  ->con_startup()
vt_map_display() con_startup() was successful()
Console: mono dummy device 80x25 vc:17-17

Now what? Miscompilation? Mis-linkage?

# rpm -q gcc binutils
gcc-3.3.3-7
binutils-2.15.90.0.3-5

Anyway, after
# echo "isa0060/serio0/input0" >/proc/bus/console/01/keyboard
# dmesg
...
keyboard: [AT Translated Set 2 keyboard] bound to [dummy device] vc:17-17

Putting these into /etc/rc.d/rc.local now
I have a dual-head 64-bit Linux machine! :-D

Thanks, Aivil, for the starting point. Next time I will
try to compile this with gcc-3.4.0, that may give some
difference.

Best regards,
Zolt=E1n B=F6sz=F6rm=E9nyi