(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? 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.

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