diff options
| author | Ingo Molnar <mingo@elte.hu> | 2008-03-28 14:28:03 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-03-28 10:16:53 -0700 |
| commit | 48d3d8263c491822d50e64547bae5f6b4a54ec59 (patch) | |
| tree | 29f12143572f7ab00f309bce82c478042a899e7a /drivers/acpi/video.c | |
| parent | e72e9c23ee025a4c063ca112ba0a6059f9ecc9b7 (diff) | |
revert "ACPI: drivers/acpi: elide a non-zero test on a result that is never 0"
Revert commit 1192aeb957402b45f311895f124e4ca41206843c ("ACPI:
drivers/acpi: elide a non-zero test on a result that is never 0")
because it turns out that thermal_cooling_device_register() does
actually return NULL if CONFIG_THERMAL is turned off (then the routine
turns into a dummy inline routine in the header files that returns NULL
unconditionally).
This was found with randconfig testing, causing a crash during bootup:
initcall 0x78878534 ran for 13 msecs: acpi_button_init+0x0/0x51()
Calling initcall 0x78878585: acpi_fan_init+0x0/0x2c()
BUG: unable to handle kernel NULL pointer dereference at 00000000
IP: [<782b8ad0>] acpi_fan_add+0x7d/0xfd
*pde = 00000000
Oops: 0000 [#1]
Modules linked in:
Pid: 1, comm: swapper Not tainted (2.6.25-rc7-sched-devel.git-x86-latest.git #14)
EIP: 0060:[<782b8ad0>] EFLAGS: 00010246 CPU: 0
EIP is at acpi_fan_add+0x7d/0xfd
EAX: b787c718 EBX: b787c400 ECX: b782ceb4 EDX: 00000007
ESI: 00000000 EDI: b787c6f4 EBP: b782cee0 ESP: b782cecc
DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
Process swapper (pid: 1, ti=b782c000 task=b7846000 task.ti=b782c000)
Stack: b787c459 00000000 b787c400 78790888 b787c60c b782cef8 782b6fb8 ffffffda
b787c60c 00000000 78790958 b782cf0c 783005d7 b787c60c 78790958 78790584
b782cf1c 783007f6 b782cf28 00000000 b782cf40 782ffc4a 78790958 b794d558
Call Trace:
[<782b6fb8>] ? acpi_device_probe+0x3e/0xdb
[<783005d7>] ? driver_probe_device+0x82/0xfc
[<783007f6>] ? __driver_attach+0x3a/0x70
[<782ffc4a>] ? bus_for_each_dev+0x3e/0x60
[<7830048c>] ? driver_attach+0x14/0x16
[<783007bc>] ? __driver_attach+0x0/0x70
[<7830006a>] ? bus_add_driver+0x9d/0x1b0
[<783008c3>] ? driver_register+0x47/0xa3
[<7813db00>] ? timespec_to_ktime+0x9/0xc
[<782b7331>] ? acpi_bus_register_driver+0x3a/0x3c
[<78878592>] ? acpi_fan_init+0xd/0x2c
[<78863656>] ? kernel_init+0xac/0x1f9
[<788635aa>] ? kernel_init+0x0/0x1f9
[<78114563>] ? kernel_thread_helper+0x7/0x10
=======================
Code: 6e 78 e8 57 44 e7 ff 58 e9 93 00 00 00 8b 55 f0 8d bb f4 02 00 00 80 4b 2d 10 8b 03 e8 87 cb ff ff 8d 83 18 03 00 00 80 63 2d ef <ff> 35 00 00 00 00 50 68 e8 9c 6e 78 e8 22 44 e7 ff b9 b6 9c 6e
EIP: [<782b8ad0>] acpi_fan_add+0x7d/0xfd SS:ESP 0068:b782cecc
---[ end trace 778e504de7e3b1e3 ]---
Kernel panic - not syncing: Attempted to kill init!
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/acpi/video.c')
| -rw-r--r-- | drivers/acpi/video.c | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index fe09b57de61..12fb44f1676 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -734,19 +734,21 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device) if (IS_ERR(device->cdev)) return; - printk(KERN_INFO PREFIX - "%s is registered as cooling_device%d\n", - device->dev->dev.bus_id, device->cdev->id); - result = sysfs_create_link(&device->dev->dev.kobj, - &device->cdev->device.kobj, - "thermal_cooling"); - if (result) - printk(KERN_ERR PREFIX "Create sysfs link\n"); - result = sysfs_create_link(&device->cdev->device.kobj, - &device->dev->dev.kobj, - "device"); - if (result) - printk(KERN_ERR PREFIX "Create sysfs link\n"); + if (device->cdev) { + printk(KERN_INFO PREFIX + "%s is registered as cooling_device%d\n", + device->dev->dev.bus_id, device->cdev->id); + result = sysfs_create_link(&device->dev->dev.kobj, + &device->cdev->device.kobj, + "thermal_cooling"); + if (result) + printk(KERN_ERR PREFIX "Create sysfs link\n"); + result = sysfs_create_link(&device->cdev->device.kobj, + &device->dev->dev.kobj, + "device"); + if (result) + printk(KERN_ERR PREFIX "Create sysfs link\n"); + } } if (device->cap._DCS && device->cap._DSS){ static int count = 0; |