diff options
| -rw-r--r-- | rust/Makefile | 8 | ||||
| -rw-r--r-- | rust/helpers/bug.c | 5 | ||||
| -rw-r--r-- | rust/kernel/.gitignore | 2 | ||||
| -rw-r--r-- | rust/kernel/bug.rs | 126 | ||||
| -rw-r--r-- | rust/kernel/generated_arch_reachable_asm.rs.S | 7 | ||||
| -rw-r--r-- | rust/kernel/generated_arch_warn_asm.rs.S | 7 | ||||
| -rw-r--r-- | rust/kernel/lib.rs | 1 |
7 files changed, 156 insertions, 0 deletions
diff --git a/rust/Makefile b/rust/Makefile index 27dec7904c3a..4e675d210dd8 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -34,6 +34,9 @@ obj-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated.o obj-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated_kunit.o always-$(subst y,$(CONFIG_RUST),$(CONFIG_JUMP_LABEL)) += kernel/generated_arch_static_branch_asm.rs +ifndef CONFIG_UML +always-$(subst y,$(CONFIG_RUST),$(CONFIG_BUG)) += kernel/generated_arch_warn_asm.rs kernel/generated_arch_reachable_asm.rs +endif # Avoids running `$(RUSTC)` when it may not be available. ifdef CONFIG_RUST @@ -540,5 +543,10 @@ $(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/build_error.o $(obj)/pin_init.o \ ifdef CONFIG_JUMP_LABEL $(obj)/kernel.o: $(obj)/kernel/generated_arch_static_branch_asm.rs endif +ifndef CONFIG_UML +ifdef CONFIG_BUG +$(obj)/kernel.o: $(obj)/kernel/generated_arch_warn_asm.rs $(obj)/kernel/generated_arch_reachable_asm.rs +endif +endif endif # CONFIG_RUST diff --git a/rust/helpers/bug.c b/rust/helpers/bug.c index e2d13babc737..a62c96f507d1 100644 --- a/rust/helpers/bug.c +++ b/rust/helpers/bug.c @@ -6,3 +6,8 @@ __noreturn void rust_helper_BUG(void) { BUG(); } + +bool rust_helper_WARN_ON(bool cond) +{ + return WARN_ON(cond); +} diff --git a/rust/kernel/.gitignore b/rust/kernel/.gitignore index 6ba39a178f30..f636ad95aaf3 100644 --- a/rust/kernel/.gitignore +++ b/rust/kernel/.gitignore @@ -1,3 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 /generated_arch_static_branch_asm.rs +/generated_arch_warn_asm.rs +/generated_arch_reachable_asm.rs diff --git a/rust/kernel/bug.rs b/rust/kernel/bug.rs new file mode 100644 index 000000000000..36aef43e5ebe --- /dev/null +++ b/rust/kernel/bug.rs @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0 + +// Copyright (C) 2024, 2025 FUJITA Tomonori <fujita.tomonori@gmail.com> + +//! Support for BUG and WARN functionality. +//! +//! C header: [`include/asm-generic/bug.h`](srctree/include/asm-generic/bug.h) + +#[macro_export] +#[doc(hidden)] +#[cfg(all(CONFIG_BUG, not(CONFIG_UML), not(CONFIG_LOONGARCH), not(CONFIG_ARM)))] +#[cfg(CONFIG_DEBUG_BUGVERBOSE)] +macro_rules! warn_flags { + ($flags:expr) => { + const FLAGS: u32 = $crate::bindings::BUGFLAG_WARNING | $flags; + const _FILE: &[u8] = file!().as_bytes(); + // Plus one for null-terminator. + static FILE: [u8; _FILE.len() + 1] = { + let mut bytes = [0; _FILE.len() + 1]; + let mut i = 0; + while i < _FILE.len() { + bytes[i] = _FILE[i]; + i += 1; + } + bytes + }; + + // SAFETY: + // - `file`, `line`, `flags`, and `size` are all compile-time constants or + // symbols, preventing any invalid memory access. + // - The asm block has no side effects and does not modify any registers + // or memory. It is purely for embedding metadata into the ELF section. + unsafe { + $crate::asm!( + concat!( + "/* {size} */", + include!(concat!(env!("OBJTREE"), "/rust/kernel/generated_arch_warn_asm.rs")), + include!(concat!(env!("OBJTREE"), "/rust/kernel/generated_arch_reachable_asm.rs"))); + file = sym FILE, + line = const line!(), + flags = const FLAGS, + size = const ::core::mem::size_of::<$crate::bindings::bug_entry>(), + ); + } + } +} + +#[macro_export] +#[doc(hidden)] +#[cfg(all(CONFIG_BUG, not(CONFIG_UML), not(CONFIG_LOONGARCH), not(CONFIG_ARM)))] +#[cfg(not(CONFIG_DEBUG_BUGVERBOSE))] +macro_rules! warn_flags { + ($flags:expr) => { + const FLAGS: u32 = $crate::bindings::BUGFLAG_WARNING | $flags; + + // SAFETY: + // - `flags` and `size` are all compile-time constants, preventing + // any invalid memory access. + // - The asm block has no side effects and does not modify any registers + // or memory. It is purely for embedding metadata into the ELF section. + unsafe { + $crate::asm!( + concat!( + "/* {size} */", + include!(concat!(env!("OBJTREE"), "/rust/kernel/generated_arch_warn_asm.rs")), + include!(concat!(env!("OBJTREE"), "/rust/kernel/generated_arch_reachable_asm.rs"))); + flags = const FLAGS, + size = const ::core::mem::size_of::<$crate::bindings::bug_entry>(), + ); + } + } +} + +#[macro_export] +#[doc(hidden)] +#[cfg(all(CONFIG_BUG, CONFIG_UML))] +macro_rules! warn_flags { + ($flags:expr) => { + // SAFETY: It is always safe to call `warn_slowpath_fmt()` + // with a valid null-terminated string. + unsafe { + $crate::bindings::warn_slowpath_fmt( + $crate::c_str!(::core::file!()).as_char_ptr(), + line!() as $crate::ffi::c_int, + $flags as $crate::ffi::c_uint, + ::core::ptr::null(), + ); + } + }; +} + +#[macro_export] +#[doc(hidden)] +#[cfg(all(CONFIG_BUG, any(CONFIG_LOONGARCH, CONFIG_ARM)))] +macro_rules! warn_flags { + ($flags:expr) => { + // SAFETY: It is always safe to call `WARN_ON()`. + unsafe { $crate::bindings::WARN_ON(true) } + }; +} + +#[macro_export] +#[doc(hidden)] +#[cfg(not(CONFIG_BUG))] +macro_rules! warn_flags { + ($flags:expr) => {}; +} + +#[doc(hidden)] +pub const fn bugflag_taint(value: u32) -> u32 { + value << 8 +} + +/// Report a warning if `cond` is true and return the condition's evaluation result. +#[macro_export] +macro_rules! warn_on { + ($cond:expr) => {{ + let cond = $cond; + if cond { + const WARN_ON_FLAGS: u32 = $crate::bug::bugflag_taint($crate::bindings::TAINT_WARN); + + $crate::warn_flags!(WARN_ON_FLAGS); + } + cond + }}; +} diff --git a/rust/kernel/generated_arch_reachable_asm.rs.S b/rust/kernel/generated_arch_reachable_asm.rs.S new file mode 100644 index 000000000000..3886a9ad3a99 --- /dev/null +++ b/rust/kernel/generated_arch_reachable_asm.rs.S @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include <linux/bug.h> + +// Cut here. + +::kernel::concat_literals!(ARCH_WARN_REACHABLE) diff --git a/rust/kernel/generated_arch_warn_asm.rs.S b/rust/kernel/generated_arch_warn_asm.rs.S new file mode 100644 index 000000000000..409eb4c2d3a1 --- /dev/null +++ b/rust/kernel/generated_arch_warn_asm.rs.S @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include <linux/bug.h> + +// Cut here. + +::kernel::concat_literals!(ARCH_WARN_ASM("{file}", "{line}", "{flags}", "{size}")) diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs index e88bc4b27d6e..11a6461e98da 100644 --- a/rust/kernel/lib.rs +++ b/rust/kernel/lib.rs @@ -57,6 +57,7 @@ pub mod auxiliary; pub mod bits; #[cfg(CONFIG_BLOCK)] pub mod block; +pub mod bug; #[doc(hidden)] pub mod build_assert; pub mod clk; |