Files
linux-apfs/drivers/gpu/drm
Maarten Lankhorst 1b6e5fd5f4 drm/radeon: add missing ttm_eu_backoff_reservation to radeon_bo_list_validate
Op 10-07-13 12:03, Markus Trippelsdorf schreef:
> On 2013.07.10 at 11:56 +0200, Maarten Lankhorst wrote:
>> Op 10-07-13 11:46, Markus Trippelsdorf schreef:
>>> On 2013.07.10 at 11:29 +0200, Maarten Lankhorst wrote:
>>>> Op 10-07-13 11:22, Markus Trippelsdorf schreef:
>>>>> By simply copy/pasting a big document under LibreOffice my system hangs
>>>>> itself up. Only a hard reset gets it working again.
>>>>> see also: https://bugs.freedesktop.org/show_bug.cgi?id=66551
>>>>>
>>>>> I've bisected the issue to:
>>>>>
>>>>> commit ecff665f5e
>>>>> Author: Maarten Lankhorst <m.b.lankhorst@gmail.com>
>>>>> Date:   Thu Jun 27 13:48:17 2013 +0200
>>>>>
>>>>>     drm/ttm: make ttm reservation calls behave like reservation calls
>>>>>
>>>>>     This commit converts the source of the val_seq counter to
>>>>>     the ww_mutex api. The reservation objects are converted later,
>>>>>     because there is still a lockdep splat in nouveau that has to
>>>>>     resolved first.
>>>>>
>>>>>     Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
>>>>>     Reviewed-by: Jerome Glisse <jglisse@redhat.com>
>>>>>     Signed-off-by: Dave Airlie <airlied@redhat.com>
>>>> Hey,
>>>>
>>>> Can you try current head with CONFIG_PROVE_LOCKING set and post the
>>>> lockdep splat from dmesg, if any? If there is any locking issue
>>>> lockdep should warn about it.  Lockdep will turn itself off after the
>>>> first splat, so if the lockdep splat happens before running the
>>>> affected parts those will have to be fixed first.
>>> There was an unrelated EDAC lockdep splat, so I simply disabled it.
>>>
>>> This is what I get:
>>>
>>> Jul 10 11:40:44 x4 kernel: ================================================
>>> Jul 10 11:40:44 x4 kernel: [ BUG: lock held when returning to user space! ]
>>> Jul 10 11:40:44 x4 kernel: 3.10.0-08587-g496322b #35 Not tainted
>>> Jul 10 11:40:44 x4 kernel: ------------------------------------------------
>>> Jul 10 11:40:44 x4 kernel: X/211 is leaving the kernel with locks still held!
>>> Jul 10 11:40:44 x4 kernel: 2 locks held by X/211:
>>> Jul 10 11:40:44 x4 kernel: #0:  (reservation_ww_class_acquire){+.+.+.}, at: [<ffffffff813279f0>] radeon_bo_list_validate+0x20/0xd0
>>> Jul 10 11:40:44 x4 kernel: #1:  (reservation_ww_class_mutex){+.+.+.}, at: [<ffffffff81309306>] ttm_eu_reserve_buffers+0x126/0x4b0
>>> Jul 10 11:40:52 x4 kernel: SysRq : Emergency Sync
>>> Jul 10 11:40:53 x4 kernel: Emergency Sync complete
>>>
>> Thanks, exactly what I thought. I missed a backoff somewhere..
>>
>> Does the below patch fix it?
> Yes. Thank you for your quick reply.

8<------
If radeon_cs_parser_relocs fails ttm_eu_backoff_reservation doesn't get called.
This left open a bug where ttm_eu_reserve_buffers succeeded but the bo's were
not unlocked afterwards:

Jul 10 11:40:44 x4 kernel: ================================================
Jul 10 11:40:44 x4 kernel: [ BUG: lock held when returning to user space! ]
Jul 10 11:40:44 x4 kernel: 3.10.0-08587-g496322b #35 Not tainted
Jul 10 11:40:44 x4 kernel: ------------------------------------------------
Jul 10 11:40:44 x4 kernel: X/211 is leaving the kernel with locks still held!
Jul 10 11:40:44 x4 kernel: 2 locks held by X/211:
Jul 10 11:40:44 x4 kernel: #0:  (reservation_ww_class_acquire){+.+.+.}, at: [<ffffffff813279f0>] radeon_bo_list_validate+0x20/0xd0
Jul 10 11:40:44 x4 kernel: #1:  (reservation_ww_class_mutex){+.+.+.}, at: [<ffffffff81309306>] ttm_eu_reserve_buffers+0x126/0x4b0
Jul 10 11:40:52 x4 kernel: SysRq : Emergency Sync
Jul 10 11:40:53 x4 kernel: Emergency Sync complete

This is a regression caused by commit ecff665f5e.
"drm/ttm: make ttm reservation calls behave like reservation calls"

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2013-07-14 10:11:27 -04:00
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2013-06-28 12:04:04 +10:00
2013-06-28 12:04:05 +10:00
2013-06-28 12:04:06 +10:00
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2013-04-30 22:20:00 +02:00
2013-06-24 06:26:50 +10:00

************************************************************
* For the very latest on DRI development, please see:      *
*     http://dri.freedesktop.org/                          *
************************************************************

The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).

The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:

    1. The DRM provides synchronized access to the graphics hardware via
       the use of an optimized two-tiered lock.

    2. The DRM enforces the DRI security policy for access to the graphics
       hardware by only allowing authenticated X11 clients access to
       restricted regions of memory.

    3. The DRM provides a generic DMA engine, complete with multiple
       queues and the ability to detect the need for an OpenGL context
       switch.

    4. The DRM is extensible via the use of small device-specific modules
       that rely extensively on the API exported by the DRM module.


Documentation on the DRI is available from:
    http://dri.freedesktop.org/wiki/Documentation
    http://sourceforge.net/project/showfiles.php?group_id=387
    http://dri.sourceforge.net/doc/

For specific information about kernel-level support, see:

    The Direct Rendering Manager, Kernel Support for the Direct Rendering
    Infrastructure
    http://dri.sourceforge.net/doc/drm_low_level.html

    Hardware Locking for the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/hardware_locking_low_level.html

    A Security Analysis of the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/security_low_level.html