Dave Airlie 13e902acc5 fbcon: fix race condition between console lock and cursor timer (v1.1) ... commit d8636a2717 upstream. So we've had a fair few reports of fbcon handover breakage between efi/vesafb and i915 surface recently, so I dedicated a couple of days to finding the problem. Essentially the last thing we saw was the conflicting framebuffer message and that was all. So after much tracing with direct netconsole writes (printks under console_lock not so useful), I think I found the race. Thread A (driver load) Thread B (timer thread) unbind_con_driver -> | bind_con_driver -> | vc->vc_sw->con_deinit -> | fbcon_deinit -> | console_lock() | | | | fbcon_flashcursor timer fires | console_lock() <- blocked for A | | fbcon_del_cursor_timer -> del_timer_sync (BOOM) Of course because all of this is under the console lock, we never see anything, also since we also just unbound the active console guess what we never see anything. Hopefully this fixes the problem for anyone seeing vesafb->kms driver handoff. v1.1: add comment suggestion from Alan. Signed-off-by: Dave Airlie <airlied@redhat.com> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Tested-by: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2012-10-02 10:30:22 -07:00
..
bitblit.c
dummycon.c
fbcon.c	fbcon: fix race condition between console lock and cursor timer (v1.1)	2012-10-02 10:30:22 -07:00
fbcon.h
fbcon_ccw.c
fbcon_cw.c
fbcon_rotate.c
fbcon_rotate.h
fbcon_ud.c
font_6x11.c
font_7x14.c
font_8x8.c
font_8x16.c
font_10x18.c
font_acorn_8x8.c
font_mini_4x6.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
font_pearl_8x8.c
font_sun8x16.c
font_sun12x22.c
fonts.c
Kconfig	Kconfig: remove a few puzzling comments	2011-10-31 10:58:48 +01:00
Makefile
mdacon.c
newport_con.c	Remove all #inclusions of asm/system.h	2012-03-28 18:30:03 +01:00
softcursor.c
sticon.c
sticore.c	parisc: move definition of PAGE0 to asm/page.h	2012-05-10 15:12:08 -07:00
tileblit.c	fbcon: Bugfix soft cursor detection in Tile Blitting	2011-03-22 16:41:08 +09:00
vgacon.c	locking, video: Annotate vga console lock as raw	2011-09-13 11:12:04 +02:00