From 5d9668f3930609ead91f39b059ef4fe53db04942 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Sat, 8 Aug 2026 11:26:08 +0900 Subject: [PATCH] rust: bug: skip arch-specific asm in `testlib` builds Running `make rusttest` with `ARCH=` set to an architecture other than the host's fails, e.g. `ARCH=arm64` on an x86_64 host: error: invalid instruction mnemonic 'brk' --> rust/kernel/bug.rs:63:17 | 63 | / concat!( 64 | | "/* {size} */", 65 | | include!(concat!(env!("OBJTREE"), "/rust/kernel/generated_arch_warn_asm.rs")), 66 | | include!(concat!(env!("OBJTREE"), "/rust/kernel/generated_arch_reachable_asm.rs"))); | |_______________________________________________________________________________________________________^ | note: instantiated into assembly here --> :1:115 | 1 | /* 8 */.pushsection __bug_table,"aw"; .align 2; 14470: .long 14471f - .;.short 2305;.align 2; .popsection; 14471:brk 0x800 | ^^^ The reason is that `rusttest` builds the `kernel` crate as a host library: it passes the `CONFIG_*` cfgs of the configured architecture, but not `--target`, so code generation happens for the host. `warn_flags!` then selects the arch-specific inline asm arm based on `CONFIG_*`, and the host assembler rejects it. This does not happen with the current `master` because `warn_on!` has no user inside the `kernel` crate itself yet, but it will as soon as one is added. Reported-by: Miguel Ojeda Closes: https://lore.kernel.org/all/CANiq72n4=fz=JNKY0Jdm8BnLa=RmHB2B7s0bO47YTJ7hygqBZg@mail.gmail.com/ Signed-off-by: FUJITA Tomonori Cc: stable@vger.kernel.org Fixes: dff64b072708 ("rust: Add warn_on macro") Link: https://patch.msgid.link/20260808022608.1125174-1-tomo@flapping.org Signed-off-by: Miguel Ojeda --- rust/kernel/bug.rs | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/rust/kernel/bug.rs b/rust/kernel/bug.rs index a09e6c9b314e..309131b1e9d0 100644 --- a/rust/kernel/bug.rs +++ b/rust/kernel/bug.rs @@ -8,6 +8,7 @@ #[macro_export] #[doc(hidden)] +#[cfg(not(testlib))] #[cfg(all(CONFIG_BUG, not(CONFIG_UML), not(CONFIG_LOONGARCH), not(CONFIG_ARM)))] #[cfg(CONFIG_DEBUG_BUGVERBOSE)] macro_rules! warn_flags { @@ -47,6 +48,7 @@ macro_rules! warn_flags { #[macro_export] #[doc(hidden)] +#[cfg(not(testlib))] #[cfg(all(CONFIG_BUG, not(CONFIG_UML), not(CONFIG_LOONGARCH), not(CONFIG_ARM)))] #[cfg(not(CONFIG_DEBUG_BUGVERBOSE))] macro_rules! warn_flags { @@ -77,6 +79,7 @@ macro_rules! warn_flags { #[macro_export] #[doc(hidden)] +#[cfg(not(testlib))] #[cfg(all(CONFIG_BUG, CONFIG_UML))] macro_rules! warn_flags { ($file:expr, $flags:expr) => { @@ -99,6 +102,7 @@ macro_rules! warn_flags { #[macro_export] #[doc(hidden)] +#[cfg(not(testlib))] #[cfg(all(CONFIG_BUG, any(CONFIG_LOONGARCH, CONFIG_ARM)))] macro_rules! warn_flags { ($file:expr, $flags:expr) => { @@ -114,7 +118,7 @@ macro_rules! warn_flags { #[macro_export] #[doc(hidden)] -#[cfg(not(CONFIG_BUG))] +#[cfg(any(testlib, not(CONFIG_BUG)))] macro_rules! warn_flags { ($file:expr, $flags:expr) => { if false {