We are pleased to announce that the Android Microconference has been accepted into the 2021 Linux Plumbers Conference. The past Android microconferences have been centered around the idea that it was primarily a synchronization point between the Android kernel team and the rest of the community to inform them on what they have been doing. With the help of last year’s focus on the Generic Kernel Image[1] (GKI), this year’s Android microconference will instead be an opportunity to foster a higher level of collaboration between the Android and Linux kernel communities. Discussions will be centered on the goal of ensuring that both the Android and Linux development moves in a lockstep fashion going forward.

Last year’s meetup achieved the following:

• Forward progress on GKI, where vendors have started contributing their core kernel changes upstream, and moving their core functionality to modules.
• fw_devlink=on by default
• ION dropped from staging in favour of dma-buf heaps
• A couple of inline encryption patch series eMMC inline encryption support add support for inline encryption to device mapper
• Forward progress on dm-user
• Open development of the protected KVM project
• More details about last years achievements

This year’s topics to be discussed include:

• Alignment issues between Android and Cgroups v2: Issues in refactoring Android’s use of cgroups to utilize cgroups v2
• Thermal: Issues around performance and thermal handling between the kernel and Android’s HAL
• Fuse/device-mapper/other storage: Discuss out-of-tree dm/storage drivers and how they might go upstream or better align with upstream efforts
• In kernel memory tracking: Tracking/account GPU (and other multi-device shared) memory and how it might fit with cgroups
• fw_devlink: Remaining fw_devlink issues to resolve, now that its enabled by default.
• Hermetic builds/Kbuild
• GKI updates: Whats new this year in GKI and where its going next year
• Rust in AOSP / Kernel / Binder: How Android is adopting rust for userland and potentially for kernel drivers
• Android Automotive OS Reference Platform: Details on recent Android Automotive work
• Community devboard/device Collaboration: Ways to better collaborate on enabling various devboard against AOSP, without needing close interlock with Google

Come and join us in the discussion of making Android a better partner with Linux.

We hope to see you there.

We are pleased to announce that the Kernel Dependability and Assurance Microconference has been accepted into the 2021 Linux Plumbers Conference.

Linux development is producing kernels at an ever increasing rate, and at the same time with arguably increasing software quality. The process of kernel development has been adapting to handle the increasing number of contributors over the years to ensure a sufficient software quality. This quality is key in that Linux is now being used in applications that require a high degree of trust that the kernel is going to behave as expected. Some of the key areas we’re seeing Linux start to be used are in medical devices, civil infrastructure, caregiving robots, automotives, etc.

Last year’s miniconference raised awareness about this topic with the wider community. Since then the ELISA team has made contributions to the Documentation and tools. The team has deployed a CI server that runs static analysis tools and syzkaller on the Linux kernel repos and is making the results of last 10 days of linux-next are made available to the community.

This year’s topics to be discussed include:

• Identify missing features that will provide assurance in safety critical systems.
• Which test coverage infrastructures are most effective to provide evidence for kernel quality assurance? How should it be measured?
• Explore ways to improve testing framework and tests in the kernel with a specific goal to increase traceability and code coverage.
• Regression Testing for safety: Prioritize configurations and tests critical and important for quality and dependability

Come and join us in the discussion on how we can assure that Linux becomes the most trusted and dependable software in the world!

We hope to see you there.

We are pleased to announce that the Open Printing Microconference has been accepted into the 2021 Linux Plumbers Conference. Over the years OpenPrinting has been actively working on improving and modernizing the way we print in Linux. We have been working on multiple areas of printing and scanning. Especially driverless print and scan technologies have helped the world do away with a lot of hassles involved in deciding on the correct driver to use and to install the same. Users can now just plug in their printer and do what they need.

Based on the discussions that we had last year, we have been able to achieve the following:

– Significant progress in deciding on the structure of PAPPL – framework/library for developing Printer Applications as a replacement of Printer Drivers.

– Progress on LPrint. Label Printer Application, implementing printing for a variety of common label and receipt printers connected via network or USB.

– Have helped us in giving shape to the Printer Application concept. Sample printer applications for HP PCL printers have been created that use PAPPL to support IPP printing from multiple operating systems. This prototype will help others looking forward to adopting this new concept of Printer Applications. First production Printer Application started from this prototype is the PostScript Printer Application.

Development is in continuous progress, see the state of the art in OpenPrinting’s monthly news posts[6].

This year’s topics to be discussed include:

• Changes in CUPS 2.4.x
  • Print sharing changes for mobile
  • OAauth support to replace Kerberos
  • Printer drivers replaced with Printer Applications
  • TLS/X.509 changes
• CUPS in containers
  • CUPS 3.0
  • Future CUPS development
  • Identify support platforms
  • Key printing system components
  • Discuss integration with Printer Applications and application stores like Snap Store
• Print Management GUI
  • Migrating from working with CUPS queues to IPP services
  • Handling legacy devices that do not handle IPP services
• Common Print Dialog Backends
  • CPDB, CUPS backend.
  • Separating GUI toolkits and the print technology support to be independent from each other.
• Printer/Scanner Driver Design and Development
  • Design, creation and Snap-packaging of Printer/Scanner Applications.

Come join us and participate in the discussion to bring Linux printing, scanning and fax a better experience.

We hope to see you there.

We are pleased to announce that the VFIO/IOMMU/PCI Microconference has been accepted into the 2021 Linux Plumbers Conference. Today’s high speed components commonly utilize the devices that implement the PCI interconnect specification and the system IOMMUs that provide memory and access control between the devices and the system resources. The features of this domain are constantly increasing with such features as:

• Address Translation Service (ATS)/Page Request Interface (PRI)
• Single-root I/O Virtualization (SR-IOV)/Process Address Space ID (PASID)
• Shared Virtual Addressing (SVA)
• Remote Direct Memory Access (RDMA)
• Peer-to-Peer DMA (P2PDMA)
• Cache Coherent Interconnect for Accelerators (CCIX)
• Compute Express Link (CXL)
• Data Object Exchange (DOE)
• Gen-Z

Last year’s meetup achieved the following:

• A path towards converting the Intel IOMMU driver for it to use DMA-IOMMU was defined
• Support for exposing devices to userspace using either VFIO mdev or userspace DMA was debated and brought a solution forward
• A discussion was held concerning drivers ability to enable PCI capabilities explicitly without current implicit support through the IOMMU drivers so that the number of newly added quirks can be reduced should there be a broken or buggy feature present. This discussion paved the way closer to a working solution
• The groundwork for improving security and management of both the internal and external (“trusted” and “untrusted”) devices was discussed defining changes that have to be completed going forward
• To ease problems with the hot-plug support, two concepts were presented and reviewed: movable BARs and movable bus number. A discourse followed during which the current issues were widely discussed and a possible solution was debated setting a tone for future work
• A proposal put forward to address the lack of endpoint function drivers ability to perform data transfer between the Root Complex (RC) and Endpoint (EP) leveraging the existing VirtIO infrastructure was reviewed and debated, where then a path forward has been identified
• A series of enhancements to IOMMU and VFIO user APIs for guest Shared Virtual Address (SVA) have been discussed with work already pending inclusion into the mainline kernel

This year’s topics to be discussed include:

• VFIO
  • Write-combine on non-x86 architectures
  • I/O Page Fault (IOPF) for passthrough devices
  • Shared Virtual Addressing (SVA) interface
  • Single-root I/O Virtualization(SRIOV)/Process Address Space ID (PASID) integration
  • PASID in SRIOV virtual functions
  • Device assignment/sub-assignment
• IOMMU
  • IOMMU virtualization
  • IOMMU drivers SVA interface
  • I/O Address Space ID Allocator (IOASID) and /dev/ioasid userspace API (uAPI) proposal
  • Possible IOMMU core changes (e.g., better integration with device-driver core, etc.)
• PCI
  • Cache Coherent Interconnect for Accelerators (CCIX)/Compute Express Link (CXL) expansion memory and accelerators management
  • I/O Address Space ID Allocator (IOASID)
  • INTX/MSI IRQ domain consolidation
  • Gen-Z interconnect fabric
  • ARM64 architecture and hardware
  • PCI native host controllers/endpoints drivers current challenges and improvements (e.g., state of PCI quirks, etc.)
  • PCI error handling and management e.g., Advanced Error Reporting (AER), Downstream Port Containment (DPC), ACPI Platform Error Interface (APEI) and Error Disconnect Recover (EDR)
  • Power management and devices supporting Active-state Power Management (ASPM)
  • Peer-to-Peer DMA (P2PDMA)
  • Resources claiming/assignment consolidation
  • Prefetchable vs non-prefetchable BAR address mappings
  • Untrusted/external devices management
  • Thunderbolt, DMA, RDMA and USB4 security

Come and join us in the discussion in helping Linux keep up with the new features being added to the PCI interconnect specification.

We hope to see you there.

We are pleased to announce that the Testing and Fuzzing Microconference has been accepted into the 2021 Linux Plumbers Conference. In spite of the huge number of products shipping with the Linux kernel which are being thoroughly tested by OEMs and distribution providers, there is still no enforced quality standard upstream. How can we make best use of all the publicly available infrastructure and test frameworks in order to fill this gap? Testing and fuzzing upstream as well as gathering results from products is crucial to keeping a project that has over 5,000 commits every month stable for all to use.

Last year’s meetup achieved the following:

• KernelCI enabled LLVM=1 Clang builds and produced initial results from kselftests and real-time tests
• KCIDB achieved multiple integrations, acting as a central collecting point for KernelCI, CKI, syzbot, etc.
• KFENCE was successfully merged.
• Clang: CFI, weeding out issued upstream, etc.
• KUnit started acting as the standard for some drivers.

This year’s topics to be discussed include:

• KernelCI: Extending coverage and improving user experience.
• Growing KCIDB, integrating more sources.
• Better sanitizers: KFENCE, improving KCSAN.
• Using Clang for better testing coverage: Now that the kernel fully supports building with clang, how can all that work be leveraged into using clang’s features?
• How to spread KUnit throughout the kernel?
• Testing in-kernel Rust code.

Come and join us in the discussion of keeping Linux being the best quality it can be.

We hope to see you there.