Re: 572994bf18ff prevents system boot

[Chuck Lever III <chuck.lever@oracle.com>]

> On Oct 4, 2021, at 10:07 AM, Thomas Zimmermann <tzimmermann@suse.de> wrote:
> 
> Hi
> 
> Am 04.10.21 um 15:34 schrieb Chuck Lever III:
>>> On Oct 4, 2021, at 3:07 AM, Thomas Zimmermann <tzimmermann@suse.de> wrote:
>>> 
>>> (cc: ainux.wang@gmail.com)
>>> 
>>> Hi
>>> 
>>> Am 03.10.21 um 20:09 schrieb Chuck Lever III:
>>>> Hi-
>>>> After updating one of my test systems to v5.15-rc, I found that it
>>>> becomes unresponsive during the later part of the boot process. A
>>>> power-on reset is necessary to recover.
>>>> I bisected to this commit:
>>>> 572994bf18ff ("drm/ast: Zero is missing in detect function")
>>> 
>>> You don't have a monitor connected, I guess?
>> Correct, my lab systems use IPMI and a browser-attached console.
>>> In that case, we now trigger the helpers that poll for connected monitors. However, the overhead seems rather extreme.
>>> 
>>> I'll have to try to reproduce this, or otherwise we can revert the commit.
>> It's strange, only that system in my lab seems to have a problem.
>> The others work fine.
>> Thanks for having a look!
> 
> Is it a HW or FW problem? Maybe a different revision?

It's possible. I don't know how to further diagnose the issue,
though. Any guidance appreciated!


> I'm asking because the problematic commit does the correct thing. If there is no VGA cable connected, the driver should poll until it detects one. The overhead should be minimal.
> 
> But I'll try to reproduce anyway.
> 
> Best regards
> Thomas
> 
>>> Best regards
>>> Thomas
>>> 
>>>> Checking out v5.15-rc3 and reverting this commit enables the system
>>>> to boot again.
>>>> 0b:00.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics Family (rev 30) (prog-if 00 [VGA controller])
>>>>         DeviceName:  ASPEED Video AST2400
>>>>         Subsystem: Super Micro Computer Inc X10SRL-F
>>>>         Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
>>>>         Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
>>>>         Interrupt: pin A routed to IRQ 18
>>>>         Region 0: Memory at fa000000 (32-bit, non-prefetchable) [size=16M]
>>>>         Region 1: Memory at fb000000 (32-bit, non-prefetchable) [size=128K]
>>>>         Region 2: I/O ports at c000 [size=128]
>>>>         Expansion ROM at 000c0000 [virtual] [disabled] [size=128K]
>>>>         Capabilities: [40] Power Management version 3
>>>>                 Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
>>>>                 Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>>>>         Capabilities: [50] MSI: Enable- Count=1/4 Maskable- 64bit+
>>>>                 Address: 0000000000000000  Data: 0000
>>>>         Kernel driver in use: ast
>>>>         Kernel modules: ast
>>>> --
>>>> Chuck Lever
>>> 
>>> -- 
>>> Thomas Zimmermann
>>> Graphics Driver Developer
>>> SUSE Software Solutions Germany GmbH
>>> Maxfeldstr. 5, 90409 Nürnberg, Germany
>>> (HRB 36809, AG Nürnberg)
>>> Geschäftsführer: Felix Imendörffer
>> --
>> Chuck Lever
> 
> -- 
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
> Geschäftsführer: Felix Imendörffer

--
Chuck Lever