ACRN Project Technical Community Meeting Minutes - 11/28/2018

Wang, Hongbo

ACRN Project TCM - 28th November 2018
1. ACRN project update
2. Chen, Zide:  PCIe configuration space emulation
Download foil from ACRN Presentation->ACRN_TCM->WW48’18
Q: do we need to passthrough PCIe bridge and the device?
A: don’t need to pass-thru PCIe bridge to the guest, but we can pass-thru PCIe device to the guests.
Q: For partition mode, will we use the same or different BDF?
A: it doesn’t matter virtual BDF is identical to physical BDF or not, as long as the virtual BDF is unique in the guest and it’s bus is 0.
Q:  for example a PCIe end device (bdf  1:0:0) is on the PCIe bridge (bdf 0:7:0), how do we pass thru end device? do we only do -s 1/0/0? or do we pass thru the PCIe bridge 0/7/0 as well? or do we need to emulate the bridge like host bridge?
A: We can pass through PCIe device to the guest, in this case “-s 1/0/0”, but don’t need to pass through PCIe bridge (0/7/0). We don’t need to emulate the PCIe bridge and attach the PCIe device to the virtual host bridge.
However, we didn’t test PCIe extensively, and it’s possible that it may need some fixes.
Q: Any performance data regarding to the HV interception? For emulated devices and pass-through devices.
A: In hypervisor, it only intercepts configuration I/O ports and the MSI-X table MMIO, and the guests are supposed to have access them mostly in the system initialization stage. So we don’t think there will have noticeable performance penalties for pass-through devices.
Q: What’s the next step for PCIe configuration space emulation?
A: Currently the PCI configuration emulation for UOS is done in device model and we are planning to move this functionality to hypervisor; Some improvements to the MSI remapping, for example, support the per-vector masking for MSI devices.
3. All: Community open discussion.
4. Next meeting agenda proposal:
WW Topic Presenter Status
WW21 ACRN roadmap introduction Ren, Jack Done
WW22 Patch submission process
ACRN feature list introduction
Wang, Hongbo
Ren, Jack
WW23 Memory Management Chen, Jascon Done
WW24 Boot flow and fast boot Wu, Binbin Done
WW25 Memory Management Chen, Jason C Done
WW26 Audio virtualization Li, Jocelyn Done
WW27 Trusty Security on ACRN Zhu, Bing’s team Done
WW28 Clear Linux and use on ACRN Du, Alek Done
WW29 GVT-g for ACRN (a.k.a AcrnGT) Gong, Zhipeng Done
WW30 Device pass-through Zhai, Edwin Done
WW31 ACRN logical partition Ren, Jack/Xu, Anthony Done
WW32 ACRN interrupt management Chen, Jason Done
WW33 ACRN ACPI virtualization Edwin Zhai Done
WW34 ACRN S3/S5 management Fengwei Yin Done
WW35 ACRN P-state/C-state management Victor Sun Done
WW36 CPU Virtualization Jason Chen Done
WW37 Joint Design: VM Configuration Options Discussion Fengwei Yin Done
WW38 Joint Design: Remove dynamic memory allocation from ACRN memory management Li, Fei Done
WW39 USB virtualization Wang, Yu Done
WW41 Interrupt Storm Mitigation Cao, Minggui Done
WW42 SBL bootloader introduction - 101 Ma, Maurice Done
WW43 SBL bootloader - 201 Ma, Maurice Done
WW44 ACRN VT-d Binbin Wu Done
WW45 ACRN update in Embedded Linux Conf Ren, Jack Done
WW46 Vhost support Wang, Yu Done
WW47 ACRN Real-Time Architecture Ren, jack Done
WW48 PCIe config space trap and emulation In HV Chen, Zide 11/28
Virtio network performance analysis Deng, Jie Plan
Virtio storage performance analysis Chen, Conghui Plan
ACRN GPIO virtualization Wang, Yu Plan
  1. 2019 Embedded World Exhibition & Conference
  1. Feb. 26-28, 2019
  2. CFP deadline: Aug. 31, 2018
  3. Nuremberg, Germany
  1. Project URL:
  1. Portal:   
  2. Source code:   
  3. email: info@...g
  4. Technical Mailing list: acrn-dev@...g
  1. Recommended Hardware platform (reference):
  1. Apollo Lake (SoC) UP2 (with serial port): AAEON UPS-APLC2-A10-0232
  2. Apollo Lake (SoC) NUC (without serial port): NUC6CAYHL (at least 8G memory)
  3. Kabylake (Core) NUC (with serial port): NUC7i5BNH
Best regards.
Tel: +86-21-6116 7445
MP: +86-1364 1793 689

Join { to automatically receive all group messages.