2021-3-22 Meeting Meeting notes
Meeting Details
Topic: linaro-open-discussion meeting
Time: March 22 , 2021 10.00 AM London
Join Zoom Meeting
https://linaro-org.zoom.us/j/4417312160
Meeting ID: 441 731 2160
One tap mobile
+16465588656,,4417312160# US (New York)
+16699009128,,4417312160# US (San Jose)
Dial by your location
+1 646 558 8656 US (New York)
+1 669 900 9128 US (San Jose)
+1 253 215 8782 US (Tacoma)
+1 301 715 8592 US (Washington D.C)
+1 312 626 6799 US (Chicago)
+1 346 248 7799 US (Houston)
877 853 5247 US Toll-free
888 788 0099 US Toll-free
Meeting ID: 441 731 2160
Find your local number: https://linaro-org.zoom.us/u/aUcYpPkSC
Attendees
Lorenzo
- Vincent
- Jammy
- James Morse
- Souvik Chakravarty
- Jonathan
- Jean-Philippe
- Shameerali
- Salil
- Barry Song
- Yunsheng Lin
- Tao Zeng
Agenda
Confirmed topics
- CXL follow up discussion
- Feedback on the virtual CPU hotplug implementation with PSCI
- AOB
Meeting Notes
- CXL on memory (Jonathan presented several new slides after the introduction in last call)
- Handling of memory on Type 2 devices (like GPU), two modes:
- Host biased (coherency is managed as part of the host SoC)
- Device biased (device issues coherence messages)
- Vikram's question: how should it be presented by Firmware?
- Problem 1: normal memory at boot can't be offlined later
- Likely to need element of BIOS control
- Problem 2: pinned memory in region
- Patch sets under review to migrate memory out of ZONE_MOVABLE on pin
- Problem 1: normal memory at boot can't be offlined later
- Generic Initiator Reminder
- GI as bridge for CXL etc.
- Handling of memory on Type 2 devices (like GPU), two modes:
- Virtual CPU hotplug
- Salil shared some figures about QEMU boot time impact by the number of CPU cores
- Pre vCPU Init
- Post vCPU Init (but pre-VGIC Init)
- Post VGIC Init
- Pre Linux Kernel Load
- Post Kernel Load (But Pre SMBIOS setup)
- LP: we need to converge and do some wrap up for proposal
- Salil to share some details about how to get the figures
- Salil shared some figures about QEMU boot time impact by the number of CPU cores
- Recording: link (password: *92a8xSE)