[PATCH 2/2] rust: io: gate ioremap doctests on CONFIG_HAS_IOMEM

Danilo Krummrich <[email protected]> Mon, 3 Aug 2026 22:02:37 +0200
Newsgroups org.kernel.vger.rust-for-linux,dev.linux.lists.driver-core,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
The doc examples in io.rs and devres.rs directly call
bindings::ioremap() and bindings::iounmap(), which do not exist when
CONFIG_HAS_IOMEM is not set. This causes build failures with
CONFIG_RUST_KERNEL_DOCTESTS=y on such configurations (e.g. s390
allnoconfig).

Gate the affected doctests with `#![cfg(CONFIG_HAS_IOMEM)]` so they are
skipped when IOMEM is unavailable.

Fixes: 3f70ebe63858 ("s390: Enable Rust support")
Signed-off-by: Danilo Krummrich <[email protected]>
---
 rust/kernel/devres.rs | 1 +
 rust/kernel/io.rs     | 1 +
 2 files changed, 2 insertions(+)

diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs
index 11ce500e9b76..8ff8aedf251a 100644
--- a/rust/kernel/devres.rs
+++ b/rust/kernel/devres.rs
@@ -59,6 +59,7 @@ struct Inner<T> {
 /// # Examples
 ///
 /// ```no_run
+/// # #![cfg(CONFIG_HAS_IOMEM)]
 /// use kernel::{
 ///     bindings,
 ///     device::{
diff --git a/rust/kernel/io.rs b/rust/kernel/io.rs
index fcc7678fd9e3..9e0c8a891656 100644
--- a/rust/kernel/io.rs
+++ b/rust/kernel/io.rs
@@ -80,6 +80,7 @@ pub fn maxsize(&self) -> usize {
 /// # Examples
 ///
 /// ```no_run
+/// # #![cfg(CONFIG_HAS_IOMEM)]
 /// use kernel::{
 ///     bindings,
 ///     ffi::c_void,
-- 
2.55.0