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") 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