Kernel having the following console/framebuffer config settings: # Character devices # CONFIG_VT=y CONFIG_VT_CONSOLE=y CONFIG_HW_CONSOLE=y CONFIG_VT_HW_CONSOLE_BINDING=y # Graphics support # CONFIG_FIRMWARE_EDID=y # CONFIG_FB is not set # Console display driver support # CONFIG_VGA_CONSOLE=y # CONFIG_VGACON_SOFT_SCROLLBACK is not set CONFIG_VIDEO_SELECT=y CONFIG_DUMMY_CONSOLE=y # CONFIG_BACKLIGHT_LCD_SUPPORT is not set When booting such a kernel with vga=normal commandline option the console displays correctly, but when setting vga=<vesa mode> the screen remains blank (though active) and console output never shows up. I would expect that when the framebuffer is not compiled the kernel should ignore vesa modes and keep console in text mode in order to be able to display console output. I can reproduce this issue on i386 hardware (tried on one Fujitsu Siemens Centrino Laptop and a HP Proliant G5 Server). I have not tried x86_64 though I assume it may also be affected by this same issue. If this is of any use I may check x86_64 using the Proliant server as it has x86_64 capable Xeon CPUs. Possibly any i386 or x86_64 hardware with vga/vesa graphics adapter is affected. System environment: SuSE 10.2, Gentoo (gcc-4.1.1)
Yes, that's known behavior. I believe this can be easily fixed, but I'm still not too sure of the repercussions. But you're probably correct, it's probably worthwhile to change this behavior.
Patch in 2.6.21-rc2-mm1. If framebuffer is not enabled, or compiled as a module, booting with VESA graphics mode will stop the boot and user will be prompted to enter a valid text mode.
Thanks, works fine. Looking forward to see it in mainline!