Re: Xen 4.21 Development Update [June-July]

[Oleksii Moisieiev <Oleksii_Moisieiev@xxxxxxxx>]

On 05/08/2025 21:19, Oleksii Kurochko wrote:
> Hello everyone,
>
> This email only tracks big items for xen.git tree. Please reply for
> items you
> would like to see in 4.21 so that people have an idea what is going on
> and
> prioritise accordingly.
>
> You're welcome to provide description and use cases of the feature you're
> working on.
>
> = Timeline =
>
> The current release schedule could be found here:
> https://wiki.xenproject.org/wiki/Xen_Project_X.YY_Release_Notes
>
> And as a reminder I would like to remind at the of this week we will have
> Last posting date (Fri Aug 08, 2025).
>
> = Updates =
>
> The following items ( the links for them could be found int the list
> below )
> were moved to completed:
>   [since Jun2 - Aug5]:
>    Added some tags: [4.21], [next-rel(s)] to the list "Full list of
> items"
>    below.
>    * x86:
>     - kexec: add kexec support to Mini-OS.
>     - x86: memcpy() / memset() (non-)ERMS flavors plus fallout
>    * Arm:
>     - SMMU handling for PCIe Passthrough on ARM.
>     - Add support for R-Car Gen4 PCI host controller.
>     - First chunk for Arm R82 and MPU support.
>     - Enable R52 support for the first chunk of MPU support
>     - ARM split hardware and control domains.
>    * RISC-V:
>     - Introduce basic UART support and interrupts for hypervisor mode.
>
>   [since May 6 - Jun2]:
>     * Hypervisor:
>       - tools: remove qemu-traditional
>     * Arm:
>       - PCI devices passthrough on Arm, part 3
>     * x86:
>       - xen: cache control improvements
>   [since 4.20 relese - May 6]:
>     * Hypervisor:
>       - Move parts of Arm's Dom0less to common code
>       - remove libxenctrl usage from xenstored
>     * Arm:
>       - Enable early bootup of Armv8-R AArch32 systems
>     * x86:
>       - x86/HVM: emulation (MMIO) improvements
>     * RISC-V:
>       - RISC-V some preinit calls.
>       - Fixes for UBSAN & GCOV support for RISC-V.
>
>
[snip]
> * [next-rel(s)] VT-d: SATC handling; ATS: tidying (v2)
>   -  Jan Beulich
>   -
> https://patchew.org/Xen/64b028be-2197-4951-ae5b-32f9eabfa84a@xxxxxxxx/
>
> *  [next-rel(s)] x86: parallelize AP bring-up during boot (v1)
>   -  Krystian Hebel
>   -
> https://lore.kernel.org/xen-devel/cover.1699982111.git.krystian.hebel@xxxxxxxxx/
>
> *  [next-rel(s)] x86/spec-ctrl: IBPB improvements (v4)
>   -  Jan Beulich
>   -
> https://patchew.org/Xen/06591b64-2f05-a4cc-a2f3-a74c3c4a76d6@xxxxxxxx/
>
> *  [next-rel(s)] Move some boot code from assembly to C (v2)
>   -  Frediano Ziglio
>   -
> https://lore.kernel.org/xen-devel/20241122093358.478774-1-frediano.ziglio@xxxxxxxxx/
>   -
> https://patchew.org/Xen/20241122093358.478774-1-frediano.ziglio@xxxxxxxxx/
>
> *  [next-rel(s)]amd-pstate CPU Performance Scaling Driver (v1)
>   -  Penny Zheng
>   -
> https://patchew.org/Xen/20241203081111.463400-1-Penny.Zheng@xxxxxxx/
>   -
> https://lore.kernel.org/xen-devel/593baee2-9bf1-4db4-86e8-015cae48dc1a@xxxxxxxx/
>
> * [next-rel(s)] x86: adventures in Address Space Isolation
>   - Roger Pau Monne <roger.pau@xxxxxxxxxx>
>   -
> https://lore.kernel.org/xen-devel/20250108142659.99490-1-roger.pau@xxxxxxxxxx/
>
> === ARM ===
>
> * [4.21?] MPU mm subsistem skeleton
>   - Luca Fancellu
>   -
> https://lore.kernel.org/xen-devel/20250312135258.1815706-1-luca.fancellu@xxxxxxx/
>   -
> https://patchew.org/Xen/20250312135258.1815706-1-luca.fancellu@xxxxxxx/
>
> * [4.21?] Add initial Xen Suspend-to-RAM support on ARM64 (v4)
>   - Mykola Kvach
>   -
> https://lore.kernel.org/xen-devel/cover.1748848482.git.mykola_kvach@xxxxxxxx/
>
> * [4.21?] xen/arm: scmi: introduce SCI SCMI SMC multi-agent support
> (->v4)
>   - Oleksii Moisieiev
>   -
> https://lore.kernel.org/xen-devel/cover.1753184487.git.oleksii_moisieiev@xxxxxxxx/
>
Hello Oleksii.

My status update on the SCMI feature upstreaming:

The v5 patch series [1] has been posted and has already received some
ACKs. I'm now waiting for the remaining maintainers to complete their
reviews. After that, I plan to drop the RFC tag and post the final version.

[1]
https://lore.kernel.org/xen-devel/cover.1753184487.git.oleksii_moisieiev@xxxxxxxx/
> * [next-rel(s)] FF-A VM to VM support (v6)
>   - Bertrand Marquis <bertrand.marquis@xxxxxxx>
>   -
> https://lore.kernel.org/xen-devel/cover.1747925287.git.bertrand.marquis@xxxxxxx/
>   -
> https://patchew.org/Xen/cover.1747925287.git.bertrand.marquis@xxxxxxx/
>
[snip]