Re: Interlaced resolutions hang the desktop

Re: Interlaced resolutions hang the desktop

[Christian König]

Hi Alberto,

well what hardware do you have?

Interlaced resolutions are not used any more on modern hardware, so they 
are not well tested.

Regards,
Christian.

Am 30.03.21 um 10:04 schrieb Alberto Salvia Novella:
> The entire desktop hangs after some minutes when using the module 
> "radeon" with an interlaced resolution.
>
> Easier to trigger by playing a video on Firefox, at least on kwin_x11. 
> Wayland didn't exhibit the problem.
>
> Other display drivers, from different computers I have tried, didn't 
> allow those interlaced resolutions all together. It seems they know 
> there will be problems.

Re: Interlaced resolutions hang the desktop

[Alex Deucher]

On Tue, Mar 30, 2021 at 12:06 PM Alberto Salvia Novella
<es20490446e@gmail.com> wrote:
>
> This is why I'm using interlaced:
>
> $ xrandr
> Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
> DisplayPort-0 disconnected (normal left inverted right x axis y axis)
> HDMI-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 16mm x 9mm
>    1920x1080i    60.00*+  50.00    59.94
>    1920x1080     24.00    23.98
>    1280x720      60.00    50.00    59.94
>    1024x768      75.03    70.07    60.00
>    832x624       74.55
>    800x600       72.19    75.00    60.32    56.25
>    720x576       50.00
>    720x576i      50.00
>    720x480       60.00    59.94
>    720x480i      60.00    59.94
>    640x480       75.00    72.81    66.67    60.00    59.94
>    720x400       70.08
> DVI-0 disconnected (normal left inverted right x axis y axis)
>
> I think the driver should only support resolutions that are progressive, but also at least of 50Hz.

The supported display modes are dictated by the monitor.  Do you still
have problems with progressive modes?  I'd hate to disable interlaced
modes if they are working fine for others.

Alex


>
> On Tue, 30 Mar 2021 at 15:41, Christian König <ckoenig.leichtzumerken@gmail.com> wrote:
>>
>> Mhm, no idea why an interlaced resolution would cause a crash. Maybe some miscalculation in the display code.
>>
>> But apart from that if you just connected your PC to a TV I also wouldn't recommend using an interlaced resolution in the first place.
>>
>> See those resolutions only exists for backward compatibility with analog hardware.
>>
>> I think we would just disable those modes instead of searching for the bug.
>>
>> Regards,
>> Christian.
>>
>> Am 30.03.21 um 11:07 schrieb Alberto Salvia Novella:
>>
>> I guessed so.
>>
>> The GPU is a Radeon HD5870, and the screen is an old Telefunken TV (TLFK22LEDPVR1).
>>
>> Since my real display got into repair I used this TV meanwhile, and to my surprise it froze the system.
>>
>> On Tue, 30 Mar 2021 at 10:15, Christian König <christian.koenig@amd.com> wrote:
>>>
>>> Hi Alberto,
>>>
>>> well what hardware do you have?
>>>
>>> Interlaced resolutions are not used any more on modern hardware, so they
>>> are not well tested.
>>>
>>> Regards,
>>> Christian.
>>>
>>> Am 30.03.21 um 10:04 schrieb Alberto Salvia Novella:
>>> > The entire desktop hangs after some minutes when using the module
>>> > "radeon" with an interlaced resolution.
>>> >
>>> > Easier to trigger by playing a video on Firefox, at least on kwin_x11.
>>> > Wayland didn't exhibit the problem.
>>> >
>>> > Other display drivers, from different computers I have tried, didn't
>>> > allow those interlaced resolutions all together. It seems they know
>>> > there will be problems.
>>>
>>
>> _______________________________________________
>> amd-gfx mailing list
>> amd-gfx@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/amd-gfx
>>
>>
> _______________________________________________
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Re: Interlaced resolutions hang the desktop

[Alex Deucher]

Does disabling pageflipping via the xorg.conf help?

Alex

On Wed, Mar 31, 2021 at 1:40 PM Christian König
<christian.koenig@amd.com> wrote:
>
> Yeah, agree that must be some kind of bug in the upper layer of the stack.
>
> Most likely some userspace component is not handling the specialties of interlacing correctly (different vblank timing every other frame).
>
> It probably only works on Intel and after restarting the display manager by coincident.
>
> Sorry, but as I said this is a use case which basically nobody is using any more and because of this the different parts of the stack are not tested well enough for this.
>
> Christian.
>
> Am 31.03.21 um 17:47 schrieb Alberto Salvia Novella:
>
> Restarting the display manager service works and, more importantly, makes the bug no longer reproducible.
>
> Restarting the window manager doesn't work.
>
> Changing display manager makes the bug still reproducible.
>
> Maybe this is due to xorg-server, isn't it?
>
> On Wed, 31 Mar 2021 at 16:55, Christian König <ckoenig.leichtzumerken@gmail.com> wrote:
>>
>> Well the hardware is working fine as far as I can see.
>>
>> Can you try to kill the X server over SSH and see if you then get some screen update?
>>
>> Regards,
>> Christian.
>>
>> Am 31.03.21 um 16:52 schrieb Alberto Salvia Novella:
>>
>> Output.
>>
>> On Wed, 31 Mar 2021 at 16:36, Christian König <christian.koenig@amd.com> wrote:
>>>
>>> Mhm strange.
>>>
>>> Can you get me the output of "sudo cat /sys/kernel/debug/dri/0/radeon_fence_info" when the problem happens?
>>>
>>> Thanks,
>>> Christian.
>>>
>>> Am 31.03.21 um 16:33 schrieb Alberto Salvia Novella:
>>>
>>> - The computer still replies to ping.
>>> - The journal shows no errors, but a few warnings.
>>> - The mouse doesn't freeze.
>>>
>>> On Wed, 31 Mar 2021 at 10:09, Christian König <christian.koenig@amd.com> wrote:
>>>>
>>>> Can you access the system over the network and see if there is anything in the system log?
>>>>
>>>> It sounds like the display stack has crashed, but when the sound keeps playing the system is most likely still responsive over network.
>>>>
>>>> Thanks,
>>>> Christian.
>>>>
>>>> Am 31.03.21 um 10:05 schrieb Alberto Salvia Novella:
>>>>
>>>> What happens is this simple: after a few minutes, about 6 or so, the entire content of the screen stays still. In some minor situations only the applications panel of KDE Plasma.
>>>>
>>>> If music is playing it continues playing, so only graphics are hung. Yet in most cases the power button won't shut down the computer, as it usually does.
>>>>
>>>> At least this is the case using kwin on x11, and not on wayland. It only happens on "radeon" and not on Intel or "radeonhd".
>>>>
>>>> On Wed, 31 Mar 2021 at 09:48, Christian König <christian.koenig@amd.com> wrote:
>>>>>
>>>>> Correct, but a TV is intended for videos only. That's why it implements only the lower HDMI standard.
>>>>>
>>>>> Interlaced transmits only halve the lines with each frame, so a 60Hz mode effectively either becomes a 30Hz mode, halving the vertical resolution or adaptive motion compensated which the know visual artifacts. Depending on what the deinterlacing setting on your TV is.
>>>>>
>>>>> You could just add a progressive 1920x540@60 or 1920x1080@30 mode manually and would have the same effect with probably better quality. See https://de.wikipedia.org/wiki/Deinterlacing for reference.
>>>>>
>>>>> If you can give us some more information what is happening when the system freeze we could try to narrow this down, but we can't spend much time on a very specific use case in a driver which is in maintenance mode.
>>>>>
>>>>> Regards,
>>>>> Christian.
>>>>>
>>>>> Am 31.03.21 um 09:21 schrieb Alberto Salvia Novella:
>>>>>
>>>>> 24fps is intended for video only. Anything interactive at 24fps, as just moving the mouse around, is extremely choppy.
>>>>>
>>>>> No way anyone would prefer that over an interlaced resolution or a lower resolution. That is, by far, the worst option.
>>>>>
>>>>> Just try it on your screen, set it to 24Hz or alike, and tell me your experience. You can't even tell where the mouse is going to go.
>>>>>
>>>>> On Wed, 31 Mar 2021 at 08:44, Christian König <christian.koenig@amd.com> wrote:
>>>>>>
>>>>>> Hi Alberto,
>>>>>>
>>>>>> well a frame rate of 24Hz is perfectly reasonable for a TV and desktop usage.
>>>>>>
>>>>>> This is probably caused by the TVs limited HDMI bandwidth and a refresh rate of 30/25 Hz for the interlaced mode isn't much better either.
>>>>>>
>>>>>> Regards,
>>>>>> Christian.
>>>>>>
>>>>>> Am 30.03.21 um 22:59 schrieb Alberto Salvia Novella:
>>>>>>
>>>>>> The frame-rate at 24Hz is extremely poor for normal desktop usage.
>>>>>>
>>>>>> If the highest resolution, aka 1080p, uses that refresh rate then the desktop will default to that frame-rate.
>>>>>>
>>>>>> Other progressive modes don't exhibit any issue.
>>>>>>
>>>>>> On Tue, 30 Mar 2021 at 18:26, Christian König <christian.koenig@amd.com> wrote:
>>>>>>>
>>>>>>> Hi Alberto,
>>>>>>>
>>>>>>> I think the driver should only support resolutions that are progressive, but also at least of 50Hz.
>>>>>>>
>>>>>>>
>>>>>>> Why do you think so?, the 24Hz resolution seems to be the native one of the display.
>>>>>>>
>>>>>>> Regards,
>>>>>>> Christian.
>>>>>>>
>>>>>>> Am 30.03.21 um 17:37 schrieb Alberto Salvia Novella:
>>>>>>>
>>>>>>> This is why I'm using interlaced:
>>>>>>>
>>>>>>> $ xrandr
>>>>>>> Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
>>>>>>> DisplayPort-0 disconnected (normal left inverted right x axis y axis)
>>>>>>> HDMI-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 16mm x 9mm
>>>>>>>    1920x1080i    60.00*+  50.00    59.94
>>>>>>>    1920x1080     24.00    23.98
>>>>>>>    1280x720      60.00    50.00    59.94
>>>>>>>    1024x768      75.03    70.07    60.00
>>>>>>>    832x624       74.55
>>>>>>>    800x600       72.19    75.00    60.32    56.25
>>>>>>>    720x576       50.00
>>>>>>>    720x576i      50.00
>>>>>>>    720x480       60.00    59.94
>>>>>>>    720x480i      60.00    59.94
>>>>>>>    640x480       75.00    72.81    66.67    60.00    59.94
>>>>>>>    720x400       70.08
>>>>>>> DVI-0 disconnected (normal left inverted right x axis y axis)
>>>>>>>
>>>>>>> I think the driver should only support resolutions that are progressive, but also at least of 50Hz.
>>>>>>>
>>>>>>> On Tue, 30 Mar 2021 at 15:41, Christian König <ckoenig.leichtzumerken@gmail.com> wrote:
>>>>>>>>
>>>>>>>> Mhm, no idea why an interlaced resolution would cause a crash. Maybe some miscalculation in the display code.
>>>>>>>>
>>>>>>>> But apart from that if you just connected your PC to a TV I also wouldn't recommend using an interlaced resolution in the first place.
>>>>>>>>
>>>>>>>> See those resolutions only exists for backward compatibility with analog hardware.
>>>>>>>>
>>>>>>>> I think we would just disable those modes instead of searching for the bug.
>>>>>>>>
>>>>>>>> Regards,
>>>>>>>> Christian.
>>>>>>>>
>>>>>>>> Am 30.03.21 um 11:07 schrieb Alberto Salvia Novella:
>>>>>>>>
>>>>>>>> I guessed so.
>>>>>>>>
>>>>>>>> The GPU is a Radeon HD5870, and the screen is an old Telefunken TV (TLFK22LEDPVR1).
>>>>>>>>
>>>>>>>> Since my real display got into repair I used this TV meanwhile, and to my surprise it froze the system.
>>>>>>>>
>>>>>>>> On Tue, 30 Mar 2021 at 10:15, Christian König <christian.koenig@amd.com> wrote:
>>>>>>>>>
>>>>>>>>> Hi Alberto,
>>>>>>>>>
>>>>>>>>> well what hardware do you have?
>>>>>>>>>
>>>>>>>>> Interlaced resolutions are not used any more on modern hardware, so they
>>>>>>>>> are not well tested.
>>>>>>>>>
>>>>>>>>> Regards,
>>>>>>>>> Christian.
>>>>>>>>>
>>>>>>>>> Am 30.03.21 um 10:04 schrieb Alberto Salvia Novella:
>>>>>>>>> > The entire desktop hangs after some minutes when using the module
>>>>>>>>> > "radeon" with an interlaced resolution.
>>>>>>>>> >
>>>>>>>>> > Easier to trigger by playing a video on Firefox, at least on kwin_x11.
>>>>>>>>> > Wayland didn't exhibit the problem.
>>>>>>>>> >
>>>>>>>>> > Other display drivers, from different computers I have tried, didn't
>>>>>>>>> > allow those interlaced resolutions all together. It seems they know
>>>>>>>>> > there will be problems.
>>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> amd-gfx mailing list
>>>>>>>> amd-gfx@lists.freedesktop.org
>>>>>>>> https://lists.freedesktop.org/mailman/listinfo/amd-gfx
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>
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