Krzysztof Helt aef7db4bd5 fbdev: fix recursive notifier and locking when fbdev console is blanked ... Fix infinite recursive notifier in the fbdev layer. This causes recursive locking. Dmitry Baryshkov found the problem and confirmed that the patch fixes the bug. After doing # echo 1 > /sys/class/graphics/fb0/blank I got the following in my kernel log: ============================================= [ INFO: possible recursive locking detected ] 2.6.27-rc6-00086-gda63874-dirty #97 --------------------------------------------- echo/1564 is trying to acquire lock: ((fb_notifier_list).rwsem){..--}, at: [<c005a384>] __blocking_notifier_call_chain+0x38/0x6c but task is already holding lock: ((fb_notifier_list).rwsem){..--}, at: [<c005a384>] __blocking_notifier_call_chain+0x38/0x6c other info that might help us debug this: 2 locks held by echo/1564: #0: (&buffer->mutex){--..}, at: [<c00ddde0>] sysfs_write_file+0x30/0x80 #1: ((fb_notifier_list).rwsem){..--}, at: [<c005a384>] __blocking_notifier_call_chain+0x38/0x6c stack backtrace: [<c0029fe4>] (dump_stack+0x0/0x14) from [<c0060ce0>] (print_deadlock_bug+0xa4/0xd0) [<c0060c3c>] (print_deadlock_bug+0x0/0xd0) from [<c0060e54>] (check_deadlock+0x148/0x17c) r6:c397a1e0 r5:c397a530 r4:c04fcf98 [<c0060d0c>] (check_deadlock+0x0/0x17c) from [<c00637e8>] (validate_chain+0x3c4/0x4f0) [<c0063424>] (validate_chain+0x0/0x4f0) from [<c0063efc>] (__lock_acquire+0x5e8/0x6b4) [<c0063914>] (__lock_acquire+0x0/0x6b4) from [<c006402c>] (lock_acquire+0x64/0x78) [<c0063fc8>] (lock_acquire+0x0/0x78) from [<c0316ca8>] (down_read+0x4c/0x60) r7:00000009 r6:ffffffff r5:c0427a40 r4:c005a384 [<c0316c5c>] (down_read+0x0/0x60) from [<c005a384>] (__blocking_notifier_call_chain+0x38/0x6c) r5:c0427a40 r4:c0427a74 [<c005a34c>] (__blocking_notifier_call_chain+0x0/0x6c) from [<c005a3d8>] (blocking_notifier_call_chain+0x20/0x28) r8:00000009 r7:c086d640 r6:c3967940 r5:00000000 r4:c38984b8 [<c005a3b8>] (blocking_notifier_call_chain+0x0/0x28) from [<c014baa0>] (fb_notifier_call_chain+0x1c/0x24) [<c014ba84>] (fb_notifier_call_chain+0x0/0x24) from [<c014c18c>] (fb_blank+0x64/0x70) [<c014c128>] (fb_blank+0x0/0x70) from [<c0155978>] (fbcon_blank+0x114/0x1bc) r5:00000001 r4:c38984b8 [<c0155864>] (fbcon_blank+0x0/0x1bc) from [<c0170ea8>] (do_blank_screen+0x1e0/0x2a0) [<c0170cc8>] (do_blank_screen+0x0/0x2a0) from [<c0154024>] (fbcon_fb_blanked+0x74/0x94) r5:c3967940 r4:00000001 [<c0153fb0>] (fbcon_fb_blanked+0x0/0x94) from [<c0154228>] (fbcon_event_notify+0x100/0x12c) r5:fffffffe r4:c39bc194 [<c0154128>] (fbcon_event_notify+0x0/0x12c) from [<c005a0d4>] (notifier_call_chain+0x38/0x7c) [<c005a09c>] (notifier_call_chain+0x0/0x7c) from [<c005a3a0>] (__blocking_notifier_call_chain+0x54/0x6c) r8:c3b51ea0 r7:00000009 r6:ffffffff r5:c0427a40 r4:c0427a74 [<c005a34c>] (__blocking_notifier_call_chain+0x0/0x6c) from [<c005a3d8>] (blocking_notifier_call_chain+0x20/0x28) r8:00000001 r7:c3a7e000 r6:00000000 r5:00000000 r4:c38984b8 [<c005a3b8>] (blocking_notifier_call_chain+0x0/0x28) from [<c014baa0>] (fb_notifier_call_chain+0x1c/0x24) [<c014ba84>] (fb_notifier_call_chain+0x0/0x24) from [<c014c18c>] (fb_blank+0x64/0x70) [<c014c128>] (fb_blank+0x0/0x70) from [<c014e450>] (store_blank+0x54/0x7c) r5:c38984b8 r4:c3b51ec4 [<c014e3fc>] (store_blank+0x0/0x7c) from [<c017981c>] (dev_attr_store+0x28/0x2c) r8:00000001 r7:c042bf80 r6:c39eba10 r5:c3967c30 r4:c38e0140 [<c01797f4>] (dev_attr_store+0x0/0x2c) from [<c00ddaac>] (flush_write_buffer+0x54/0x68) [<c00dda58>] (flush_write_buffer+0x0/0x68) from [<c00dde08>] (sysfs_write_file+0x58/0x80) r8:c3b51f78 r7:c3bcb070 r6:c39eba10 r5:00000001 r4:00000001 [<c00dddb0>] (sysfs_write_file+0x0/0x80) from [<c009de04>] (vfs_write+0xb8/0x148) [<c009dd4c>] (vfs_write+0x0/0x148) from [<c009e384>] (sys_write+0x44/0x70) r7:00000004 r6:c3bcb070 r5:00000000 r4:00000000 [<c009e340>] (sys_write+0x0/0x70) from [<c0025d00>] (ret_fast_syscall+0x0/0x2c) r6:4001b000 r5:00000001 r4:401dc658 Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl> Reported-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Testted-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2008-10-03 18:22:17 -07:00
..
aty	radeonfb: fix accel engine hangs	2008-08-12 16:07:28 -07:00
backlight	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
console	fbdev: fix recursive notifier and locking when fbdev console is blanked	2008-10-03 18:22:17 -07:00
display
geode	lxfb: fix console blanking	2008-07-24 10:47:40 -07:00
i810
intelfb
kyro
logo
matrox	matrox maven: convert to a new-style i2c driver	2008-08-12 16:07:29 -07:00
mbx
nvidia
omap	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
pnx4008	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
riva
savage
sis
vermilion	removed unused #include <linux/version.h>'s	2008-08-23 12:14:12 -07:00
68328fb.c
acornfb.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
acornfb.h
am200epd.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
amba-clcd.c
amifb.c	drivers/video/amifb.c cleanups	2008-07-24 10:47:40 -07:00
arcfb.c
arkfb.c	removed unused #include <linux/version.h>'s	2008-08-23 12:14:12 -07:00
asiliantfb.c
atafb_iplan2p2.c
atafb_iplan2p4.c
atafb_iplan2p8.c
atafb_mfb.c
atafb_utils.h
atafb.c
atafb.h
atmel_lcdfb.c	atmel_lcdfb: disable LCD and DMA engines when suspending	2008-09-13 14:41:52 -07:00
au1100fb.c
au1100fb.h
au1200fb.c
au1200fb.h
bf54x-lq043fb.c	Blackfin arch: move include/asm-blackfin header files to arch/blackfin	2008-08-27 10:51:02 +08:00
bfin-t350mcqb-fb.c	lcd: add lcd_device to check_fb() entry in lcd_ops	2008-07-24 10:47:40 -07:00
bt431.h
bt455.h
bw2.c
c2p.c
c2p.h
carminefb_regs.h
carminefb.c
carminefb.h
cfbcopyarea.c
cfbfillrect.c
cfbimgblt.c
cg3.c
cg6.c
cg14.c
chipsfb.c
cirrusfb.c	cirrusfb: check_par fixes	2008-09-02 19:21:38 -07:00
clps711xfb.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
cobalt_lcdfb.c	fbdev: add new Cobalt LCD framebuffer driver	2008-07-24 10:47:40 -07:00
controlfb.c
controlfb.h
cyber2000fb.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
cyber2000fb.h
cyblafb.c
dnfb.c
edid.h
efifb.c
epson1355fb.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
fb_ddc.c
fb_defio.c	fbdefio: add set_page_dirty handler to deferred IO FB	2008-08-20 15:40:32 -07:00
fb_draw.h
fb_notify.c
fb_sys_fops.c
fbcmap.c
fbcvt.c
fbmem.c	fbdefio: add set_page_dirty handler to deferred IO FB	2008-08-20 15:40:32 -07:00
fbmon.c	fbdev: width and height are unsigned	2008-07-24 10:47:39 -07:00
fbsysfs.c
ffb.c
fm2fb.c
fsl-diu-fb.c	freescale DIU: bug fix: add sanity check for AOI position	2008-08-15 08:35:43 -07:00
fsl-diu-fb.h
g364fb.c
gbefb.c	gbefb: cmap FIFO timeout	2008-07-30 09:41:47 -07:00
gxt4500.c
hecubafb.c
hgafb.c
hitfb.c	video: Fix up hp6xx driver build regressions.	2008-07-30 02:16:12 +09:00
hpfb.c
igafb.c
imacfb.c
imsttfb.c
imxfb.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
imxfb.h
Kconfig	video: sh7760fb: SH7760/SH7763 LCDC framebuffer driver	2008-07-24 10:47:41 -07:00
leo.c
macfb.c	make macfb_setup() static	2008-07-26 12:00:12 -07:00
macmodes.c
macmodes.h
Makefile	video: Kill off leaked CONFIG_FB_SH7343VOU reference.	2008-07-29 06:39:26 +09:00
maxinefb.c
metronomefb.c
modedb.c
n411.c
neofb.c	neofb: drop the xtimings structure	2008-07-24 10:47:41 -07:00
offb.c
output.c
p9100.c
platinumfb.c
platinumfb.h
pm2fb.c	pm2fb: free cmap memory on module remove	2008-08-20 15:40:31 -07:00
pm3fb.c
pmag-aa-fb.c
pmag-ba-fb.c
pmagb-b-fb.c
ps3fb.c
pvr2fb.c	sh: More header path fixups for mach dir refactoring.	2008-07-29 22:10:01 +09:00
pxafb.c	[ARM] pxafb: fix the warning of incorrect lccr when lcd_conn is specified	2008-08-16 16:39:16 +01:00
pxafb.h
q40fb.c
s1d13xxxfb.c
s3c2410fb.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
s3c2410fb.h
s3fb.c	removed unused #include <linux/version.h>'s	2008-08-23 12:14:12 -07:00
sa1100fb.c	[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach	2008-08-07 09:55:48 +01:00
sa1100fb.h
sbuslib.c
sbuslib.h
sgivwfb.c
sh7760fb.c	sh7760fb: write colormap value to hardware	2008-07-28 16:30:21 -07:00
sh_mobile_lcdcfb.c	video: export sh_mobile_lcdc panel size	2008-08-11 20:17:55 +09:00
skeletonfb.c	skeletonfb: update to correct platform driver usage	2008-07-24 10:47:39 -07:00
sm501fb.c	sm501: fixup allocation code to be 64bit resource compliant	2008-07-24 10:47:40 -07:00
sstfb.c
sticore.h	video/console/stico{n,re}.c: make code static	2008-07-26 12:00:12 -07:00
stifb.c	video/stifb.c: make 2 functions static	2008-07-26 12:00:12 -07:00
sunxvr500.c
sunxvr2500.c
svgalib.c
syscopyarea.c
sysfillrect.c
sysimgblt.c
tcx.c
tdfxfb.c	tdfxfb: fix frame buffer name overrun	2008-09-02 19:21:39 -07:00
tgafb.c
tridentfb.c
uvesafb.c
valkyriefb.c
valkyriefb.h
vesafb.c
vfb.c
vga16fb.c
vgastate.c
vt8623fb.c	removed unused #include <linux/version.h>'s	2008-08-23 12:14:12 -07:00
w100fb.c
w100fb.h
xen-fbfront.c
xilinxfb.c	removed unused #include <linux/version.h>'s	2008-08-23 12:14:12 -07:00