Re: unregister_framebuffer() and cursor
From: "Antonino A. Daplas" <adaplas@gmail.com>
Date: 2007-05-25 21:25:40
On Fri, 2007-05-25 at 12:13 +0200, Geert Uytterhoeven wrote:
On Fri, 4 May 2007, Antonino A. Daplas wrote:quoted
On Fri, 2007-05-04 at 10:50 +0200, Geert Uytterhoeven wrote:quoted
It looks like unregister_framebuffer() doesn't cause fbcon_del_cursor_timer() to be called. Hence if cursor_timer_handler() runs, it will try to schedule work on fb_info.queue, which is no longer valid, and queue_work() will BUG_ON(). Or am I missing something?The console cursor is not part of fbdev. fbcon_del_cursor_timer() is done in fbcon_exit() in fbcon.c. You cannot (or, rather, should not) call unregister_framebuffer() unless fbcon unbinds the underlying driver.Indeed, when unbinding the console first using echo 0 > /sys/class/vtconsole/vtcon1/bind the problem no longer happens on halt (Geoff: and ps3-hack-fbcon-shutdown.diff is no longer needed). However there are still a few remaining issues: - unbinding requires CONFIG_VT_HW_CONSOLE_BINDING=y, - unbinding can be done using sysfs only (for now), - worse, unbinding may fail, e.g. if the console is in graphics mode due to running X. Our problem is that we have to shutdown ps3fb on reboot/kexec, to release the hypervisor resources used by ps3fb. If unbinding fails, we cannot do that.
Both you and drmfb has the same problem, and Jesse submitted a patch that will unbind fbcon prior to unregister_framebuffer(). The patch needs a few tweaks but is fine by me in principle. Search lkml for [PATCH 1/3] allow console unregistration. As for the first, maybe a 'select VT_HW_CONSOLE_BINDING if FRAMEBUFFER_CONSOLE' under ps3fb? As for the second and third concerns, Jesse's patch would take care of that. Tony ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/