+ uaccess-decouple-inline_copy_from_user-and-config_rust.patch added to mm-nonmm-unstable branch

+ uaccess-decouple-inline_copy_from_user-and-config_rust.patch added to mm-nonmm-unstable branch

[Andrew Morton]

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The patch titled
     Subject: uaccess: decouple INLINE_COPY_FROM_USER and CONFIG_RUST
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     uaccess-decouple-inline_copy_from_user-and-config_rust.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/uaccess-decouple-inline_copy_from_user-and-config_rust.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Yury Norov (NVIDIA)" <yury.norov@gmail.com>
Subject: uaccess: decouple INLINE_COPY_FROM_USER and CONFIG_RUST
Date: Thu, 23 Oct 2025 13:16:06 -0400

Commit 1f9a8286bc0c ("uaccess: always export _copy_[from|to]_user with
CONFIG_RUST") exports _copy_{from,to}_user() unconditionally, if RUST is
enabled.  This pollutes exported symbols namespace, and spreads RUST
ifdefery in core files.

It's better to declare a corresponding helper under the rust/helpers,
similarly to how non-underscored copy_{from,to}_user() is handled.

Link: https://lkml.kernel.org/r/20251023171607.1171534-1-yury.norov@gmail.com
Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Trevor Gross <tmgross@umich.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/usercopy.c         |    4 ++--
 rust/helpers/uaccess.c |   12 ++++++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

--- a/lib/usercopy.c~uaccess-decouple-inline_copy_from_user-and-config_rust
+++ a/lib/usercopy.c
@@ -12,7 +12,7 @@
 
 /* out-of-line parts */
 
-#if !defined(INLINE_COPY_FROM_USER) || defined(CONFIG_RUST)
+#if !defined(INLINE_COPY_FROM_USER)
 unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n)
 {
 	return _inline_copy_from_user(to, from, n);
@@ -20,7 +20,7 @@ unsigned long _copy_from_user(void *to,
 EXPORT_SYMBOL(_copy_from_user);
 #endif
 
-#if !defined(INLINE_COPY_TO_USER) || defined(CONFIG_RUST)
+#if !defined(INLINE_COPY_TO_USER)
 unsigned long _copy_to_user(void __user *to, const void *from, unsigned long n)
 {
 	return _inline_copy_to_user(to, from, n);
--- a/rust/helpers/uaccess.c~uaccess-decouple-inline_copy_from_user-and-config_rust
+++ a/rust/helpers/uaccess.c
@@ -13,3 +13,15 @@ unsigned long rust_helper_copy_to_user(v
 {
 	return copy_to_user(to, from, n);
 }
+
+#ifdef INLINE_COPY_FROM_USER
+unsigned long rust_helper__copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+	return _inline_copy_from_user(to, from, n);
+}
+
+unsigned long rust_helper__copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+	return _inline_copy_to_user(to, from, n);
+}
+#endif
_

Patches currently in -mm which might be from yury.norov@gmail.com are

uaccess-decouple-inline_copy_from_user-and-config_rust.patch