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Minute takers according to this page
July 12, 2021
Participants:
- Stephen (Renesas)
- Adam (Kernkonzept)
- Matti (Opensynergy)
- Gunnar (GENIVI)
- Oleksandr (EPAM)
- Kai (EB)
Minutes
- Gunnar: I met with Arm (Bernhard) and Francois Ozog (active in Linaro). We discussed virtual platform specification, if there are additional automotive-specific hardware that need VIRTIO support (e.g. do we have a proposal for FM tuner? (No, not currently))
Discussion on the usage of virtual platforms as a hardware-portability solution:
- Gunnar: We se this trend. I'd like to analyze this idea further, compared to for example just making stable user-space APIs and creating new kernel drivers for new hardware.
- => Is this not just shifting portability work "somewhere else". Let's analyze how "virtual platform API is stable" is different from "user-space API is stable" (i.e. just port drivers to new hardware..)
- Adam: BSPs that add a lot of patches to Linux get stuck on older versions. Not using mainline. Updating to new kernel drivers difficult (N.B. officially no APIs are stable inside Linux kernel)
- Matti: Linux kernel in particular, is an operating system kernel and a hardware-abstraction at the same time, which is challenging.
- Future challenges: Value-add for SoCs could be difficult if the [hardware abstraction] API is limiting.
- The virtual platform / VIRTIO / Trout and others. It seems the "new" distinction is a clear focus on a hardware-abstraction layer?
- (partly agreed, discussed the existence of firmware as one abstraction already used, and on PC side the hardware it self was standardized, etc. Overall, a complex reality)
- Summary:
- Kernel updates are driven by fast development, security issues, etc.
- Fast changes, no internal API stability guarantee etc. = updating drivers is a major issue.
- It seems this situation can't be avoided, and the industry is looking for a solution to the challenge.
- The theory seems to be that keeping API stable and efficiently port to new hardware, could be more feasible to do in the virtual platform.
- Discussion turned to evaluating the effort (that the industry is also considering) to create new kernel(s) instead, as a Linux alternative (for safety, and development concerns as shown above).
E.g. if they have a POSIX API, is that "enough". => No... could still be a large effort to port existing functionality.- Gunnar: As an example, consider systemd which early on used Linux-only APIs. And then a lot of functionality built on systemd. Such examples makes porting software a challenge.
- Also discussed how large part of Linux' functionality is actually used in practice in the industry?
- Matti: (Explicit example that shows the current situation)
io_uring recently added to Linux. It accelerates applications a lot. A hardware vendor that is able to use these latest features could have an advantage (hardware itself not faster, but the software runs faster).
- => With a virtual platform abstraction, updating to a new kernel with the new features should be feasible.
June 2021
- Regular meetings held every week. No specific meeting minutes written. Results in AVPS and topic planning (link below)
- AVPS v2.0 release.
- Working on deep-dive topic planning
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