From 5cc5e030bce2ec97ae5cdb2c1b94a98b1047b3fa Mon Sep 17 00:00:00 2001
From: Baptiste Lepers <baptiste.lepers@gmail.com>
Date: Tue, 12 Aug 2025 15:26:56 +0200
Subject: rust: mm: mark VmaNew as transparent
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Unsafe code in VmaNew's methods assumes that the type has the same layout
as the inner `bindings::vm_area_struct`.  This is not guaranteed by the
default struct representation in Rust, but requires specifying the
`transparent` representation.

Link: https://lkml.kernel.org/r/20250812132712.61007-1-baptiste.lepers@gmail.com
Fixes: dcb81aeab406 ("mm: rust: add VmaNew for f_ops->mmap()")
Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
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: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Trevor Gross <tmgross@umich.edu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 rust/kernel/mm/virt.rs | 1 +
 1 file changed, 1 insertion(+)

(limited to 'rust/kernel')

diff --git a/rust/kernel/mm/virt.rs b/rust/kernel/mm/virt.rs
index 6086ca981b06..a1bfa4e19293 100644
--- a/rust/kernel/mm/virt.rs
+++ b/rust/kernel/mm/virt.rs
@@ -209,6 +209,7 @@ impl VmaMixedMap {
 ///
 /// For the duration of 'a, the referenced vma must be undergoing initialization in an
 /// `f_ops->mmap()` hook.
+#[repr(transparent)]
 pub struct VmaNew {
     vma: VmaRef,
 }
-- 
cgit v1.2.3


From c09461a0d24fba8a847a37a381626141da22d8ee Mon Sep 17 00:00:00 2001
From: Alice Ryhl <aliceryhl@google.com>
Date: Wed, 27 Aug 2025 13:12:16 +0000
Subject: rust: use the new name Location::file_as_c_str() in Rust >= 1.91.0

As part of the stabilization of Location::file_with_nul(), it was brought
up that the with_nul() suffix usually means something else in Rust APIs,
so the API is being renamed prior to stabilization [1].

Thus, use the new name on new rustc versions.

Link: https://www.github.com/rust-lang/rust/pull/145928 [1]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20250827-file_as_c_str-v1-1-d3f5a3916a9c@google.com
[ Kept `cfg` separation. Reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 init/Kconfig       |  3 +++
 rust/kernel/lib.rs | 15 ++++++++++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

(limited to 'rust/kernel')

diff --git a/init/Kconfig b/init/Kconfig
index 836320251219..e7459cbea6ca 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -145,6 +145,9 @@ config RUSTC_HAS_UNNECESSARY_TRANSMUTES
 config RUSTC_HAS_FILE_WITH_NUL
 	def_bool RUSTC_VERSION >= 108900
 
+config RUSTC_HAS_FILE_AS_C_STR
+	def_bool RUSTC_VERSION >= 109100
+
 config PAHOLE_VERSION
 	int
 	default $(shell,$(srctree)/scripts/pahole-version.sh $(PAHOLE))
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index ed53169e795c..fef97f2a5098 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -296,7 +296,7 @@ macro_rules! asm {
 
 /// Gets the C string file name of a [`Location`].
 ///
-/// If `file_with_nul()` is not available, returns a string that warns about it.
+/// If `Location::file_as_c_str()` is not available, returns a string that warns about it.
 ///
 /// [`Location`]: core::panic::Location
 ///
@@ -310,8 +310,8 @@ macro_rules! asm {
 ///     let caller = core::panic::Location::caller();
 ///
 ///     // Output:
-///     // - A path like "rust/kernel/example.rs" if file_with_nul() is available.
-///     // - "<Location::file_with_nul() not supported>" otherwise.
+///     // - A path like "rust/kernel/example.rs" if `file_as_c_str()` is available.
+///     // - "<Location::file_as_c_str() not supported>" otherwise.
 ///     let caller_file = file_from_location(caller);
 ///
 ///     // Prints out the message with caller's file name.
@@ -326,7 +326,12 @@ macro_rules! asm {
 /// ```
 #[inline]
 pub fn file_from_location<'a>(loc: &'a core::panic::Location<'a>) -> &'a core::ffi::CStr {
-    #[cfg(CONFIG_RUSTC_HAS_FILE_WITH_NUL)]
+    #[cfg(CONFIG_RUSTC_HAS_FILE_AS_C_STR)]
+    {
+        loc.file_as_c_str()
+    }
+
+    #[cfg(all(CONFIG_RUSTC_HAS_FILE_WITH_NUL, not(CONFIG_RUSTC_HAS_FILE_AS_C_STR)))]
     {
         loc.file_with_nul()
     }
@@ -334,6 +339,6 @@ pub fn file_from_location<'a>(loc: &'a core::panic::Location<'a>) -> &'a core::f
     #[cfg(not(CONFIG_RUSTC_HAS_FILE_WITH_NUL))]
     {
         let _ = loc;
-        c"<Location::file_with_nul() not supported>"
+        c"<Location::file_as_c_str() not supported>"
     }
 }
-- 
cgit v1.2.3