RustInQemu: Difference between revisions

Latest revision as of 12:50, 2 May 2025

For the old RustInQemu page, see RustInQemu/2022

Active effort

Current state
Documentation
Past updates: January 2025 | November 2024

Past efforts

[RFC v3 00/32] Rust binding for QAPI and qemu-ga QMP handler examples
on patchew on lore
Subject: [RFC 0/6] scripts: Rewrite simpletrace printer in Rust
Date: Mon, 27 May 2024 16:14:15 +0800
RFC v1

Work in progress

Paolo

Waiting for Meson 1.8.1: "objects:", rustdoc,
Later: pinned_init... maybe use MaybeUninit as a first step?

Manos

Zhao

Kevin

Executing async code, block driver implementations
- https://lore.kernel.org/qemu-devel/20250211214328.640374-1-kwolf@redhat.com/

Bugs

Add BQL abstraction for tests - avoid running them with "--test-threads 1"
Distros would prefer to link libstd dynamically; Rust-enabled QEMU binaries are huge

Possible project targets

Nice things to have

Remove need for manual "meson subprojects update --reset" when updating packagefiles/
Improve tool integration
- Run code checks a la "meson test --suite codecheck"? (clippy and rustfmt)
Place rustdoc output for master somewhere?
split qemu_api into multiple crates
distros need dynamically linked libstd
- rewrite all main()s in Rust and use -C prefer-dynamic?
- or should Meson be able to link C programs with rlibs?

New code to write

more QOM procedural macros
- generate qdev properties
- generate parts of TypeInfo?
- monomorphization of T: IsA<Class> to &T (like the momo crate)
feature parity for pl011
safe object creation with pinned_init, originating from Linux)
Generic Rust<->C interop, Error (https://github.com/bonzini/rust-qemu)
DMA (investigate vm-memory?)
Trace/log (Summer of Code)

Improved clippy coverage in CI?

run clippy as part of "make check"
add to CI a fallible job that runs on nightly clippy with -Dclippy::complexity -Dclippy::perf -Dclippy::suspicious -Dclippy::style -Dunknown_lints. the job should generally pass, and if a new lint triggers it probably should be added to Cargo.toml as either "allow" (rare) or "deny" (possibly after adding #[allow()] to the source).

Miscellanea

qemu-bridge-helper.c Re-write SUID C executable with useful features.

Bindings

visitors/QOM properties, could be interesting for hw/sensor/tmp105.c...
complete vmstate bindings (needs const_refs_static in Rust 1.83.0, Zhao+Paolo have a prototype)

Devices

hw/block/pflash_cfi01.c, hw/block/pflash_cfi02.c (claimed, WIP)
- needs block bindings
hw/timer/i8254.c (claimed, WIP)
hw/mem/nvdimm.c (suggested by Manos)

@@ Line 1: / Line 1: @@
 For the old RustInQemu page, see [[RustInQemu/2022]]
-== Active efforts in 2024 ==
+== Active effort ==
-* <code>Subject: [RFC 0/6] scripts: Rewrite simpletrace printer in Rust</code><br /><code>Date: Mon, 27 May 2024 16:14:15 +0800</code><br />[https://lore.kernel.org/qemu-devel/20240527081421.2258624-1-zhao1.liu@intel.com/ RFC v1]
+* [https://lore.kernel.org/qemu-devel/d3d1944e-2482-4aa7-b621-596246a08107@gnu.org/ Current state]
-* ARM PL011 UART device model in Rust<br /><code>Subject: [RFC PATCH v1 0/6] Implement ARM PL011 in Rust</code><br /><code>Date: Mon, 10 Jun 2024 21:22:35 +0300</code><br />[https://lore.kernel.org/qemu-devel/cover.rust-pl011-rfc-v1.git.manos.pitsidianakis@linaro.org/ RFC v1] [https://lore.kernel.org/qemu-devel/rust-pl011-rfc-v2.git.manos.pitsidianakis@linaro.org v2]
+* [https://www.qemu.org/docs/master/devel/rust.html Documentation]
-** Meson integration
+* Past updates: [https://lore.kernel.org/qemu-devel/17ad81c3-98fc-44c2-8f65-f5e2cc07030b@gnu.org/ January 2025] |  [https://lore.kernel.org/all/cc40943e-dec1-4890-a1d9-579350ce296f@pbonzini.local/ November 2024]
-** Bindings generation
 == Past efforts ==
 * <code>[RFC v3 00/32] Rust binding for QAPI and qemu-ga QMP handler examples</code><br />[https://patchew.org/QEMU/20210907121943.3498701-1-marcandre.lureau@redhat.com/ on patchew] [https://lore.kernel.org/qemu-devel/20210907121943.3498701-1-marcandre.lureau@redhat.com/ on lore]
+* <code>Subject: [RFC 0/6] scripts: Rewrite simpletrace printer in Rust</code><br /><code>Date: Mon, 27 May 2024 16:14:15 +0800</code><br />[https://lore.kernel.org/qemu-devel/20240527081421.2258624-1-zhao1.liu@intel.com/ RFC v1]
-== Minimum supported version ==
+== Work in progress ==
-* 1.56.0: 2021 edition
+=== Paolo ===
-* 1.59.0: const <tt>CStr::from_bytes_with_nul_unchecked</tt> (needed by cstr crate, see below)
+* Waiting for Meson 1.8.1: "objects:", rustdoc,
-* 1.64.0: <tt>std::ffi::c_*</tt> (can use libc or std::os::raw)
+* Later: pinned_init... maybe use MaybeUninit as a first step?
-* 1.74.0: Clippy can be configured in Cargo.toml
-* 1.77.0: C string literals, offset_of!
-**alternative: cstr crate, [https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=10a22a9b8393abd7b541d8fc844bc0df with_offsets macro]
-== TODO ==
+=== Manos ===
-[https://patchew.org/QEMU/rust-pl011-rfc-v4.git.manos.pitsidianakis@linaro.org/ Done]:
+=== Zhao ===
-* module structure should resemble the C part of the tree?
-* only generate bindings.rs.inc once
-* disabling the cast_ptr_alignment lint is too broad
-[https://lore.kernel.org/qemu-devel/9a83a260-4f4c-477b-a6e1-c8d78d1f3039@redhat.com/ To do (patch available)]:
+=== Kevin ===
-* update bundled meson to 1.5.0
+* Executing async code, block driver implementations
-* add support for --rustc and RUSTC environment variables
+** https://lore.kernel.org/qemu-devel/20250211214328.640374-1-kwolf@redhat.com/
-* remove --no-include-path-detection from bindgen invocation
-* rename subprojects to use Meson 1.5.0+ convention and add meson.override_dependency() call
-* add support for cross compilation of Rust subprojects (<tt>native: true</tt> for deps of procedural macro crates)
-* fix licenses for Rust subprojects
-* fix cfgs so that proc-macro2 can be compiled with 1.63.0
-* demonstrate patching of subprojects (needed for bilge-impl to support 1.63.0)
-After commit:
+== Bugs ==
-* add more safety docs
+* Add BQL abstraction for tests - avoid running them with "--test-threads 1"
-* trait to generate all-zero structs without having to type "unsafe { MaybeUninit::zeroed().assume_init() }"
+* [https://github.com/mesonbuild/meson/issues/8828 Distros would prefer to link libstd dynamically]; Rust-enabled QEMU binaries are huge
-* use ctor instead of non-portable linker magic, and the cstr crate instead of CStr statics or c""
-* TODO comments when the code is doing potential undefined behavior
-* single cargo workspace for clippy etc.?
-* CI integration
-** clean up lints (see below)
-* lower minimum supported version in QEMU code too (Debian needs 1.63.0)
-* eliminate undefined behavior:
-** no aliasing of &mut
-** use MaybeUninit in instance_init (long-term: investigate [https://docs.rs/pinned-init/ pinned_init crate, originating from Linux])
-other experiments at https://github.com/bonzini/rust-qemu
+== Possible project targets ==
-* Generic Rust<->C interop, Error, QOM reference counting
-* Chardev
-* MemoryRegion, SysbusDevice
-== Ideas for lints without breaking CI ==
+=== Nice things to have ===
-See https://github.com/bonzini/rust-qemu/commit/95b25f7c5f4e2694a85a5503050cc98da7562c7c
+* Remove need for manual "meson subprojects update --reset" when updating packagefiles/
-* run clippy as part of "make check", possibly only if Rust is newer than some version (1.74.0 so that clippy can be configured in Cargo.toml?)
+* Improve tool integration
-* deny many individual lints, do not deny groups (complexity, perf, style, suspicious) on regular builds. allow unknown_lints.
+** Run code checks a la "meson test --suite codecheck"? (clippy and rustfmt)
+* Place rustdoc output for master somewhere?
+* split qemu_api into multiple crates
+* distros need dynamically linked libstd
+** rewrite all main()s in Rust and use [https://github.com/mesonbuild/meson/issues/14224 -C prefer-dynamic]?
+** or should Meson be able to link C programs with rlibs?
+=== New code to write===
+* more QOM procedural macros
+** generate qdev properties
+** generate parts of TypeInfo?
+** monomorphization of <tt>T: IsA&lt;Class&gt;</tt> to <tt>&T</tt> (like the momo crate)
+* feature parity for pl011
+* safe object creation with [https://docs.rs/pinned-init/ pinned_init, originating from Linux])
+* Generic Rust<->C interop, Error (https://github.com/bonzini/rust-qemu)
+* DMA (investigate vm-memory?)
+* Trace/log (Summer of Code)
+=== Improved clippy coverage in CI? ===
+* run clippy as part of "make check"
 * add to CI a fallible job that runs on nightly clippy with <tt>-Dclippy::complexity -Dclippy::perf -Dclippy::suspicious -Dclippy::style -Dunknown_lints</tt>. the job should generally pass, and if a new lint triggers it probably should be added to Cargo.toml as either "allow" (rare) or "deny" (possibly after adding #[allow()] to the source).
-== Possible project targets ==
 === Miscellanea  ===
-- <code>qemu-bridge-helper.c</code> Re-write SUID C executable with useful features.
+* <code>qemu-bridge-helper.c</code> Re-write SUID C executable with useful features.
-=== Devices  ===
+=== Bindings ===
-- <code>hw/block/pflash_cfi01.c</code>, <code>hw/block/pflash_cfi02.c</code> (claimed, WIP)
+* visitors/QOM properties, could be interesting for <code>hw/sensor/tmp105.c</code>...
+* complete vmstate bindings (needs const_refs_static in Rust 1.83.0, Zhao+Paolo have a prototype)
-- <code>hw/mem/nvdimm.c</code> (suggested by [[User:Manos|Manos]])
+=== Devices  ===
-- <code>hw/timer/i8254.c</code> (claimed, WIP)
+* <code>hw/block/pflash_cfi01.c</code>, <code>hw/block/pflash_cfi02.c</code> (claimed, WIP)
+** needs block bindings
+* <code>hw/timer/i8254.c</code> (claimed, WIP)
+* <code>hw/mem/nvdimm.c</code> (suggested by [[User:Manos|Manos]])
 [[Category:RustInQemu]]