2 files changed, 47 insertions, 0 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d3e5f36bb01e..e62271da937f 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2710,6 +2710,40 @@ config HYPERV_TESTING
 
 endmenu # "Kernel Testing and Coverage"
 
+menu "Rust hacking"
+
+config RUST_DEBUG_ASSERTIONS
+	bool "Debug assertions"
+	depends on RUST
+	help
+	  Enables rustc's `-Cdebug-assertions` codegen option.
+
+	  This flag lets you turn `cfg(debug_assertions)` conditional
+	  compilation on or off. This can be used to enable extra debugging
+	  code in development but not in production. For example, it controls
+	  the behavior of the standard library's `debug_assert!` macro.
+
+	  Note that this will apply to all Rust code, including `core`.
+
+	  If unsure, say N.
+
+config RUST_OVERFLOW_CHECKS
+	bool "Overflow checks"
+	default y
+	depends on RUST
+	help
+	  Enables rustc's `-Coverflow-checks` codegen option.
+
+	  This flag allows you to control the behavior of runtime integer
+	  overflow. When overflow-checks are enabled, a Rust panic will occur
+	  on overflow.
+
+	  Note that this will apply to all Rust code, including `core`.
+
+	  If unsure, say Y.
+
+endmenu # "Rust"
+
 source "Documentation/Kconfig"
 
 endmenu # Kernel hacking
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 3c1853a9d1c0..c414a8d9f1ea 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -2246,6 +2246,9 @@ int __init no_hash_pointers_enable(char *str)
 }
 early_param("no_hash_pointers", no_hash_pointers_enable);
 
+/* Used for Rust formatting ('%pA'). */
+char *rust_fmt_argument(char *buf, char *end, void *ptr);
+
 /*
  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
  * by an extra set of alphanumeric characters that are extended format
@@ -2372,6 +2375,10 @@ early_param("no_hash_pointers", no_hash_pointers_enable);
  *
  * Note: The default behaviour (unadorned %p) is to hash the address,
  * rendering it useful as a unique identifier.
+ *
+ * There is also a '%pA' format specifier, but it is only intended to be used
+ * from Rust code to format core::fmt::Arguments. Do *not* use it from C.
+ * See rust/kernel/print.rs for details.
  */
 static noinline_for_stack
 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
@@ -2444,6 +2451,12 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 		return device_node_string(buf, end, ptr, spec, fmt + 1);
 	case 'f':
 		return fwnode_string(buf, end, ptr, spec, fmt + 1);
+	case 'A':
+		if (!IS_ENABLED(CONFIG_RUST)) {
+			WARN_ONCE(1, "Please remove %%pA from non-Rust code\n");
+			return error_string(buf, end, "(%pA?)", spec);
+		}
+		return rust_fmt_argument(buf, end, ptr);
 	case 'x':
 		return pointer_string(buf, end, ptr, spec);
 	case 'e':