Merge pull request #18 from Rust-for-Linux/fix/ci

Fix CI

Author: antoyo

.github/workflows/ci.yaml

@@ -93,6 +93,12 @@ jobs:
       # TODO: remove if this patch is indeed not necessary. (It seems the patch is now included upstream.)
       # - run: git -C linux apply ../ci/x86-boot-Use-std-gnu11-to-fix-build-with-GCC-15.patch
 
+      # TODO: remove when fixed upstream.
+      - run: git -C linux apply ../ci/0001-Use-inline-always-for-bitfield-test-conversions.patch
+
+      # TODO: remove when fixed upstream.
+      - run: git -C linux apply ../ci/0002-Path-qualify-zerocopy-extern-in-rusttestlib-kernel.patch
+
       # Setup: `busybox`.
       - run: |
           git clone --depth 1 -b 1_30_1 https://github.com/mirror/busybox
@@ -254,7 +260,11 @@ jobs:
           grep '] rust_print: Info message (level 6) with args$'         qemu-stdout
           grep '] rust_print: A line that is continued with args$'       qemu-stdout
 
-      - run: grep '] ok 7 rust_doctests_kernel$' qemu-stdout
+      - run: |
+          # Print the result line for debugging.
+          grep -E '\] ok [0-9]+ rust_doctests_kernel$' qemu-stdout || true
+
+          grep '] ok 8 rust_doctests_kernel$' qemu-stdout
 
       - run: python ci/check_panics.py qemu-stdout
 

0001-Use-inline-always-for-bitfield-test-conversions.patch

@@ -0,0 +1,41 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Antoni Boucher <bouanto@zoho.com>
+Date: Mon, 20 Jul 2026 00:00:00 -0500
+Subject: [PATCH] Use #[inline(always)] for bitfield test conversions
+
+The `From<MemoryType>`/`From<Priority>` impls in the `bitfield` KUnit
+tests forward to `Bounded::from_expr`, which uses `build_assert!`. That
+assertion is meant to be optimized out on the (statically valid) success
+path. rustc_codegen_gcc only manages to fold it away once the constant
+enum values from the test bodies are visible, which requires the whole
+call chain to be inlined. The generated `bitfield!` setters and
+`from_expr` are already `#[inline(always)]`; these two `From` impls are
+the only remaining out-of-line links, so an out-of-line copy carrying an
+un-eliminated call to `rust_build_error` is emitted and the vmlinux link
+fails with `undefined reference to rust_build_error`.
+
+Force-inlining these conversions lets the constants reach `build_assert!`
+so the branch is folded away, matching the codegen LLVM already produces.
+---
+ rust/kernel/bitfield.rs | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/rust/kernel/bitfield.rs b/rust/kernel/bitfield.rs
+--- a/rust/kernel/bitfield.rs
++++ b/rust/kernel/bitfield.rs
+@@ -581,6 +581,7 @@
+     }
+
+     impl From<MemoryType> for Bounded<u64, 4> {
++        #[inline(always)]
+         fn from(mt: MemoryType) -> Bounded<u64, 4> {
+             Bounded::from_expr(mt as u64)
+         }
+@@ -606,6 +607,7 @@
+     }
+
+     impl From<Priority> for Bounded<u16, 2> {
++        #[inline(always)]
+         fn from(p: Priority) -> Bounded<u16, 2> {
+             Bounded::from_expr(p as u16)
+         }

0002-Path-qualify-zerocopy-extern-in-rusttestlib-kernel.patch

@@ -0,0 +1,38 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Antoni Boucher <bouanto@zoho.com>
+Date: Mon, 20 Jul 2026 00:00:00 -0500
+Subject: [PATCH] rust: path-qualify the zerocopy extern in rusttestlib-kernel
+
+Since nightly-2025-11-23 the Rust sysroot ships a precompiled `zerocopy`
+crate (`libzerocopy-<hash>.rmeta`). `rusttestlib-kernel` builds the kernel
+crate as a host test library with a bare `--extern zerocopy` and
+`-L rust/test`, so rustc finds two candidates for the crate -- the
+in-tree `rust/test/libzerocopy.rlib` and the sysroot one -- and fails:
+
+    error[E0464]: multiple candidates for `rmeta` dependency `zerocopy` found
+
+The other rules that name `zerocopy` are unaffected: the rustdoc/doctest
+rules pass `--sysroot=/dev/null`, and `rusttest-macros` only pulls
+`zerocopy` in transitively through `--extern kernel`, which rustc
+resolves unambiguously by crate hash.
+
+Point the direct dependency at the in-tree rlib so the sysroot copy is
+never considered. This only shows up with a recent toolchain, which the
+GCC backend uses (rustc_codegen_gcc pins nightly-2026-07-14); the LLVM
+backend still builds against an older nightly without the sysroot crate.
+---
+ rust/Makefile | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/rust/Makefile b/rust/Makefile
+--- a/rust/Makefile
++++ b/rust/Makefile
+@@ -342,7 +342,7 @@ rusttestlib-pin_init: $(src)/pin-init/src/lib.rs rusttestlib-macros \
+ rusttestlib-kernel: private rustc_target_flags = --extern ffi \
+     --extern build_error --extern macros --extern pin_init \
+     --extern bindings --extern uapi \
+-    --extern zerocopy --extern zerocopy_derive
++    --extern zerocopy=$(objtree)/$(obj)/test/libzerocopy.rlib --extern zerocopy_derive
+ rusttestlib-kernel: $(src)/kernel/lib.rs rusttestlib-bindings rusttestlib-uapi \
+     rusttestlib-build_error rusttestlib-pin_init $(obj)/$(libmacros_name) \
+     $(obj)/bindings.o rusttestlib-zerocopy rusttestlib-zerocopy_derive FORCE

rfl-rust.config

@@ -17,3 +17,13 @@ AX88796B_RUST_PHY=y
 
 CONFIG_KUNIT=y
 CONFIG_RUST_KERNEL_DOCTESTS=y
+
+# Other test suites from the `kernel` crate (i.e. `kunit_tests`, `#[test]`).
+CONFIG_RUST_KUNIT_TESTS=y
+CONFIG_RUST_ALLOCATOR_KUNIT_TEST=y
+CONFIG_RUST_KVEC_KUNIT_TEST=y
+CONFIG_RUST_BITMAP_KUNIT_TEST=y
+CONFIG_RUST_KUNIT_SELFTEST=y
+CONFIG_RUST_STR_KUNIT_TEST=y
+CONFIG_RUST_ATOMICS_KUNIT_TEST=y
+CONFIG_RUST_BITFIELD_KUNIT_TEST=y