[PATCH 20/34] drm/doc: Repleace LOCKING kerneldoc sections in drm_modes.c

[Dave Airlie]

On Tue, Mar 11, 2014 at 8:30 PM, Daniel Vetter <daniel.vetter at ffwll.ch> wrote:
> There's not really any value in stating that no locking is needed. And
> even if the comment is useful, a check for the right mutex at the
> beginning of the function is better since that can't be ingored as
> easily as a bit of documentation.
>
> Note that drm_mode_probed_add in drm_crtc.c is also changed, the next
> patch will move this into drm_modes.c
>
> v2: Don't add locking WARN_ONs where it is not strictly required (i.e.
> the two functions to validate/prune mode lists).

This made radeon blow up hard, I kinda expect other drivers also,


>Mar 20 01:14:21 crydee kernel: ------------[ cut here ]------------
Mar 20 01:14:21 crydee kernel: WARNING: CPU: 3 PID: 882 at
/home/airlied/kernel/linux-2.6/drivers/gpu/drm/drm_crtc.c:94
drm_warn_on_modeset_not_all_locked+0x48/0x76 [drm]()
Mar 20 01:14:21 crydee kernel: Modules linked in: firewire_ohci
firewire_core crc_itu_t ehci_pci ohci_pci ehci_hcd ohci_hcd radeon(+)
hwmon i2c_algo_bit drm_kms_helper ttm drm i2c_core
Mar 20 01:14:21 crydee kernel: CPU: 3 PID: 882 Comm: systemd-udevd Not
tainted 3.14.0-rc7+ #67
Mar 20 01:14:21 crydee kernel: Hardware name: Gigabyte Technology Co.,
Ltd. GA-A75M-UD2H/GA-A75M-UD2H, BIOS F4 09/16/2011
Mar 20 01:14:21 crydee kernel:  0000000000000000 ffff88022311f9c8
ffffffff814b5b21 0000000000000000
Mar 20 01:14:21 crydee kernel:  ffff88022311fa00 ffffffff81039e11
ffffffffa001882f ffff880036b92000
Mar 20 01:14:21 crydee kernel:  ffff880224c85000 ffff880224c85690
0000000000000000 ffff88022311fa10
Mar 20 01:14:21 crydee kernel: Call Trace:
Mar 20 01:14:21 crydee kernel:  [<ffffffff814b5b21>] dump_stack+0x4d/0x66
Mar 20 01:14:21 crydee kernel:  [<ffffffff81039e11>]
warn_slowpath_common+0x7a/0x93
Mar 20 01:14:21 crydee kernel:  [<ffffffffa001882f>] ?
drm_warn_on_modeset_not_all_locked+0x48/0x76 [drm]
Mar 20 01:14:21 crydee kernel:  [<ffffffff81039ec9>]
warn_slowpath_null+0x15/0x17
Mar 20 01:14:21 crydee kernel:  [<ffffffffa001882f>]
drm_warn_on_modeset_not_all_locked+0x48/0x76 [drm]
Mar 20 01:14:21 crydee kernel:  [<ffffffffa00853b4>]
drm_helper_disable_unused_functions+0x11/0x103 [drm_kms_helper]
Mar 20 01:14:21 crydee kernel:  [<ffffffffa00c39ed>]
radeon_fbdev_init+0xb2/0xcf [radeon]
Mar 20 01:14:21 crydee kernel:  [<ffffffffa00bf623>]
radeon_modeset_init+0x763/0x951 [radeon]
Mar 20 01:14:21 crydee kernel:  [<ffffffffa00a21f3>]
radeon_driver_load_kms+0xc5/0x171 [radeon]
Mar 20 01:14:21 crydee kernel:  [<ffffffffa0013c53>]
drm_dev_register+0x7f/0xf8 [drm]
Mar 20 01:14:21 crydee kernel:  [<ffffffffa0015e12>]
drm_get_pci_dev+0xfe/0x1c8 [drm]
Mar 20 01:14:21 crydee kernel:  [<ffffffff81078ac0>] ? trace_hardirqs_on+0xd/0xf
Mar 20 01:14:21 crydee kernel:  [<ffffffffa009f341>]
radeon_pci_probe+0xa8/0xaf [radeon]
Mar 20 01:14:21 crydee kernel:  [<ffffffff81285376>] local_pci_probe+0x38/0x7d
Mar 20 01:14:21 crydee kernel:  [<ffffffff81285481>] pci_device_probe+0xc6/0xec
Mar 20 01:14:21 crydee kernel:  [<ffffffff813149a5>]
driver_probe_device+0x98/0x1b3
Mar 20 01:14:21 crydee kernel:  [<ffffffff81314b54>] __driver_attach+0x5c/0x7e
Mar 20 01:14:21 crydee kernel:  [<ffffffff81314af8>] ? __device_attach+0x38/0x38
Mar 20 01:14:21 crydee kernel:  [<ffffffff813130ae>] bus_for_each_dev+0x79/0x83
Mar 20 01:14:21 crydee kernel:  [<ffffffff8131452c>] driver_attach+0x19/0x1b
Mar 20 01:14:21 crydee kernel:  [<ffffffff813141ee>] bus_add_driver+0x109/0x1d3
Mar 20 01:14:21 crydee kernel:  [<ffffffff81315095>] driver_register+0x89/0xc5
Mar 20 01:14:21 crydee kernel:  [<ffffffff81284acd>]
__pci_register_driver+0x5b/0x5e
Mar 20 01:14:21 crydee kernel:  [<ffffffffa01c1000>] ? 0xffffffffa01c0fff
Mar 20 01:14:21 crydee kernel:  [<ffffffffa0015f45>]
drm_pci_init+0x69/0xec [drm]
Mar 20 01:14:21 crydee kernel:  [<ffffffffa01c1000>] ? 0xffffffffa01c0fff
Mar 20 01:14:21 crydee kernel:  [<ffffffffa01c1097>]
radeon_init+0x97/0xb5 [radeon]

Dave.