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  1. 05 Sep, 2011 8 commits
  3. 02 Sep, 2011 4 commits
    • Bruno Prémont's avatar
      fb: sh-mobile: Fix deadlock risk between lock_fb_info() and console_lock() · 4a47a0e0
      Bruno Prémont authored 
      Following on Herton's patch "fb: avoid possible deadlock caused by
fb_set_suspend" which moves lock_fb_info() out of fb_set_suspend()
to its callers, correct sh-mobile's locking around call to
fb_set_suspend() and the same sort of deaklocks with console_lock()
due to order of taking the lock.

console_lock() must be taken while fb_info is already locked and fb_info
must be locked while calling fb_set_suspend().
Signed-off-by: default avatarBruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: default avatarGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: stable@kernel.org
      4a47a0e0
    • Herton Ronaldo Krzesinski's avatar
      fb: avoid possible deadlock caused by fb_set_suspend · 9e769ff3
      Herton Ronaldo Krzesinski authored 
      A lock ordering issue can cause deadlocks: in framebuffer/console code,
all needed struct fb_info locks are taken before acquire_console_sem(),
in places which need to take console semaphore.

But fb_set_suspend is always called with console semaphore held, and
inside it we call lock_fb_info which gets the fb_info lock, inverse
locking order of what the rest of the code does. This causes a real
deadlock issue, when we write to state fb sysfs attribute (which calls
fb_set_suspend) while a framebuffer is being unregistered by
remove_conflicting_framebuffers, as can be shown by following show
blocked state trace on a test program which loads i915 and runs another
forked processes writing to state attribute:

Test process with semaphore held and trying to get fb_info lock:
..
fb-test2      D 0000000000000000     0   237    228 0x00000000
 ffff8800774f3d68 0000000000000082 00000000000135c0 00000000000135c0
 ffff880000000000 ffff8800774f3fd8 ffff8800774f3fd8 ffff880076ee4530
 00000000000135c0 ffff8800774f3fd8 ffff8800774f2000 00000000000135c0
Call Trace:
 [<ffffffff8141287a>] __mutex_lock_slowpath+0x11a/0x1e0
 [<ffffffff814142f2>] ? _raw_spin_lock_irq+0x22/0x40
 [<ffffffff814123d3>] mutex_lock+0x23/0x50
 [<ffffffff8125dfc5>] lock_fb_info+0x25/0x60
 [<ffffffff8125e3f0>] fb_set_suspend+0x20/0x80
 [<ffffffff81263e2f>] store_fbstate+0x4f/0x70
 [<ffffffff812e7f70>] dev_attr_store+0x20/0x30
 [<ffffffff811c46b4>] sysfs_write_file+0xd4/0x160
 [<ffffffff81155a26>] vfs_write+0xc6/0x190
 [<ffffffff81155d51>] sys_write+0x51/0x90
 [<ffffffff8100c012>] system_call_fastpath+0x16/0x1b
..
modprobe process stalled because has the fb_info lock (got inside
unregister_framebuffer) but waiting for the semaphore held by the
test process which is waiting to get the fb_info lock:
..
modprobe      D 0000000000000000     0   230    218 0x00000000
 ffff880077a4d618 0000000000000082 0000000000000001 0000000000000001
 ffff880000000000 ffff880077a4dfd8 ffff880077a4dfd8 ffff8800775a2e20
 00000000000135c0 ffff880077a4dfd8 ffff880077a4c000 00000000000135c0
Call Trace:
 [<ffffffff81411fe5>] schedule_timeout+0x215/0x310
 [<ffffffff81058051>] ? get_parent_ip+0x11/0x50
 [<ffffffff814130dd>] __down+0x6d/0xb0
 [<ffffffff81089f71>] down+0x41/0x50
 [<ffffffff810629ac>] acquire_console_sem+0x2c/0x50
 [<ffffffff812ca53d>] unbind_con_driver+0xad/0x2d0
 [<ffffffff8126f5f7>] fbcon_event_notify+0x457/0x890
 [<ffffffff814144ff>] ? _raw_spin_unlock_irqrestore+0x1f/0x50
 [<ffffffff81058051>] ? get_parent_ip+0x11/0x50
 [<ffffffff8141836d>] notifier_call_chain+0x4d/0x70
 [<ffffffff8108a3b8>] __blocking_notifier_call_chain+0x58/0x80
 [<ffffffff8108a3f6>] blocking_notifier_call_chain+0x16/0x20
 [<ffffffff8125dabb>] fb_notifier_call_chain+0x1b/0x20
 [<ffffffff8125e6ac>] unregister_framebuffer+0x7c/0x130
 [<ffffffff8125e8b3>] remove_conflicting_framebuffers+0x153/0x180
 [<ffffffff8125eef3>] register_framebuffer+0x93/0x2c0
 [<ffffffffa0331112>] drm_fb_helper_single_fb_probe+0x252/0x2f0 [drm_kms_helper]
 [<ffffffffa03314a3>] drm_fb_helper_initial_config+0x2f3/0x6d0 [drm_kms_helper]
 [<ffffffffa03318dd>] ? drm_fb_helper_single_add_all_connectors+0x5d/0x1c0 [drm_kms_helper]
 [<ffffffffa037b588>] intel_fbdev_init+0xa8/0x160 [i915]
 [<ffffffffa0343d74>] i915_driver_load+0x854/0x12b0 [i915]
 [<ffffffffa02f0e7e>] drm_get_pci_dev+0x19e/0x360 [drm]
 [<ffffffff8141821d>] ? sub_preempt_count+0x9d/0xd0
 [<ffffffffa0386f91>] i915_pci_probe+0x15/0x17 [i915]
 [<ffffffff8124481f>] local_pci_probe+0x5f/0xd0
 [<ffffffff81244f89>] pci_device_probe+0x119/0x120
 [<ffffffff812eccaa>] ? driver_sysfs_add+0x7a/0xb0
 [<ffffffff812ed003>] driver_probe_device+0xa3/0x290
 [<ffffffff812ed1f0>] ? __driver_attach+0x0/0xb0
 [<ffffffff812ed29b>] __driver_attach+0xab/0xb0
 [<ffffffff812ed1f0>] ? __driver_attach+0x0/0xb0
 [<ffffffff812ebd3e>] bus_for_each_dev+0x5e/0x90
 [<ffffffff812ecc2e>] driver_attach+0x1e/0x20
 [<ffffffff812ec6f2>] bus_add_driver+0xe2/0x320
 [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915]
 [<ffffffff812ed536>] driver_register+0x76/0x140
 [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915]
 [<ffffffff81245216>] __pci_register_driver+0x56/0xd0
 [<ffffffffa02f1264>] drm_pci_init+0xe4/0xf0 [drm]
 [<ffffffffa03aa000>] ? i915_init+0x0/0x96 [i915]
 [<ffffffffa02e84a8>] drm_init+0x58/0x70 [drm]
 [<ffffffffa03aa094>] i915_init+0x94/0x96 [i915]
 [<ffffffff81002194>] do_one_initcall+0x44/0x190
 [<ffffffff810a066b>] sys_init_module+0xcb/0x210
 [<ffffffff8100c012>] system_call_fastpath+0x16/0x1b
..

fb-test2 which reproduces above is available on kernel.org bug #26232.
To solve this issue, avoid calling lock_fb_info inside fb_set_suspend,
and move it out to where needed (callers of fb_set_suspend must call
lock_fb_info before if needed). So far, the only place which needs to
call lock_fb_info is store_fbstate, all other places which calls
fb_set_suspend are suspend/resume hooks that should not need the lock as
they should be run only when processes are already frozen in
suspend/resume.

References: https://bugzilla.kernel.org/show_bug.cgi?id=26232Signed-off-by: default avatarHerton Ronaldo Krzesinski <herton@mandriva.com.br>
Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: stable@kernel.org
      9e769ff3
    • Manuel Lauss's avatar
      fbdev: au1200fb: silence debug output · f49446eb
      Manuel Lauss authored 
      it's annoying and takes up way too much space in dmesg.
Signed-off-by: default avatarManuel Lauss <manuel.lauss@googlemail.com>
Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
      f49446eb
    • Anatolij Gustschin's avatar
      video: mb862xx-i2c: fix for reliable decoder register access · 363d58f5
      Anatolij Gustschin authored 
      Increase delay when polling for tx status. This fixes
the unreliable video decoder i2c register access.
Signed-off-by: default avatarAnatolij Gustschin <agust@denx.de>
Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
      363d58f5
  5. 01 Sep, 2011 3 commits
    • Tomi Valkeinen's avatar
      fbdev: fix parsing of standard timings · 43dcd13b
      Tomi Valkeinen authored 
      The standard timings parses uses 1:1 dimensions when the ratio in the
EDID data is 0. However, for EDID 1.3 and later the dimensions are 16:10
when the ratio is 0.

Pass the version and revision numbers to get_std_timing() which can then
make the right decision about dimensions.
Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
      43dcd13b
    • Axel Lin's avatar
      video: nuc900fb: remove include of mach/clkdev.h · f88a91cc
      Axel Lin authored 
      Since commit aa3831cf
"ARM: Consolidate the clkdev header files",
the header file arch/arm/mach-nuc93x/include/mach/clkdev.h is removed.

This patch fixes below build error:

drivers/video/nuc900fb.c:42:25: error: mach/clkdev.h: No such file or directory
make[2]: *** [drivers/video/nuc900fb.o] Error 1
make[1]: *** [drivers/video] Error 2
make: *** [drivers] Error 2
Signed-off-by: default avatarAxel Lin <axel.lin@gmail.com>
Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
      f88a91cc
    • Axel Lin's avatar
      video: mxsfb: add missing include of linux/module.h · 36893674
      Axel Lin authored 
      Include linux/module.h to fix below build error:

                 from drivers/video/mxsfb.c:42:
arch/arm/mach-mxs/include/mach/memory.h:22:1: warning: this is the location of the previous definition
drivers/video/mxsfb.c:574: error: 'THIS_MODULE' undeclared here (not in a function)
drivers/video/mxsfb.c:893: warning: data definition has no type or storage class
drivers/video/mxsfb.c:893: warning: type defaults to 'int' in declaration of 'MODULE_DEVICE_TABLE'
drivers/video/mxsfb.c:893: warning: parameter names (without types) in function declaration
drivers/video/mxsfb.c:917: error: expected declaration specifiers or '...' before string constant
drivers/video/mxsfb.c:917: warning: data definition has no type or storage class
drivers/video/mxsfb.c:917: warning: type defaults to 'int' in declaration of 'MODULE_DESCRIPTION'
drivers/video/mxsfb.c:917: warning: function declaration isn't a prototype
drivers/video/mxsfb.c:918: error: expected declaration specifiers or '...' before string constant
drivers/video/mxsfb.c:918: warning: data definition has no type or storage class
drivers/video/mxsfb.c:918: warning: type defaults to 'int' in declaration of 'MODULE_AUTHOR'
drivers/video/mxsfb.c:918: warning: function declaration isn't a prototype
drivers/video/mxsfb.c:919: error: expected declaration specifiers or '...' before string constant
drivers/video/mxsfb.c:919: warning: data definition has no type or storage class
drivers/video/mxsfb.c:919: warning: type defaults to 'int' in declaration of 'MODULE_LICENSE'
drivers/video/mxsfb.c:919: warning: function declaration isn't a prototype
make[2]: *** [drivers/video/mxsfb.o] Error 1
make[1]: *** [drivers/video] Error 2
make: *** [drivers] Error 2
Signed-off-by: default avatarAxel Lin <axel.lin@gmail.com>
Signed-off-by: default avatarFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
      36893674
  7. 30 Aug, 2011 1 commit
  9. 29 Aug, 2011 1 commit
  11. 24 Aug, 2011 8 commits
  13. 22 Aug, 2011 6 commits
  15. 21 Aug, 2011 4 commits
  17. 20 Aug, 2011 4 commits
  19. 19 Aug, 2011 1 commit
    • Jiaying Zhang's avatar
      ext4: flush any pending end_io requests before DIO reads w/dioread_nolock · dccaf33f
      Jiaying Zhang authored 
      There is a race between ext4 buffer write and direct_IO read with
dioread_nolock mount option enabled. The problem is that we clear
PageWriteback flag during end_io time but will do
uninitialized-to-initialized extent conversion later with dioread_nolock.
If an O_direct read request comes in during this period, ext4 will return
zero instead of the recently written data.

This patch checks whether there are any pending uninitialized-to-initialized
extent conversion requests before doing O_direct read to close the race.
Note that this is just a bandaid fix. The fundamental issue is that we
clear PageWriteback flag before we really complete an IO, which is
problem-prone. To fix the fundamental issue, we may need to implement an
extent tree cache that we can use to look up pending to-be-converted extents.
Signed-off-by: default avatarJiaying Zhang <jiayingz@google.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
      dccaf33f
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