From: David Gow <davidgow@xxxxxxxxxx>
commit c682e4c37d2b8ba3bde1125cbbea4ee88824b4e2 upstream.
The rust_fmt_argument function is called from printk() to handle the %pA
format specifier.
Since it's called from C, we should mark it extern "C" to make sure it's
ABI compatible.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 247b365dc8dc ("rust: add `kernel` crate")
Signed-off-by: David Gow <davidgow@xxxxxxxxxx>
Reviewed-by: Gary Guo <gary@xxxxxxxxxxx>
Reviewed-by: Björn Roy Baron <bjorn3_gh@xxxxxxxxxxxxxx>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@xxxxxxxxx>
[Applied `rustfmt`]
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
rust/kernel/print.rs | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/rust/kernel/print.rs
+++ b/rust/kernel/print.rs
@@ -18,7 +18,11 @@ use crate::bindings;
// Called from `vsprintf` with format specifier `%pA`.
#[no_mangle]
-unsafe fn rust_fmt_argument(buf: *mut c_char, end: *mut c_char, ptr: *const c_void) -> *mut c_char {
+unsafe extern "C" fn rust_fmt_argument(
+ buf: *mut c_char,
+ end: *mut c_char,
+ ptr: *const c_void,
+) -> *mut c_char {
use fmt::Write;
// SAFETY: The C contract guarantees that `buf` is valid if it's less than `end`.
let mut w = unsafe { RawFormatter::from_ptrs(buf.cast(), end.cast()) };
