From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B81AD423A80 for ; Thu, 3 Sep 2026 12:43:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788439439; cv=none; b=DnJwwVDrh0g0FzTvHwtgs3M98a34CPFQMScF9bkhOWlc/3mHBVPhaeKp1O8aBJvNguz91SrjRWzDvrgKknR529HuLA050JkmeYc39Ly9IKASqYzkkZq2D1tJqgq92wAa90hbGgLwY2M0tArx85tEH5qr1/mDt++DBR4xXstVBnY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788439439; c=relaxed/simple; bh=u0nby/QpdReBsxZJMUgy/p+LX/63fi+79LqpagDD8AI=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=aUQ/jANLzbp1Pdpz0/4cEuONu4u4dwQiLVd2vGx4x/daBfQ9oLQBomPezswYUbH/DAwHCHNUMmlMWhxh1c3pRUqkN+toqPO+p2Y2tyAURaU39AI6MYBTdnjlE31NEx0hWwutNLzdLfjGGOnGiG1zJehg9NwPekPPl8rffBEDL5U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uKieLv9R; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="uKieLv9R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C21131F000E9; Thu, 3 Sep 2026 12:43:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788439437; bh=xmGfZQMqmLKUx6INofu1+xkCgyoMirlRN0J7gD+EX/c=; h=Subject:To:Cc:From:Date; b=uKieLv9RglnY0AolwlSd6nz1H0knSB0wh3AuHyGy+ZXYeupJzTVifvUt7QqFcpw1G SXeh7lL1K15XIPqW0c8HLe5Xprrv+4i+WswgUUysacQ7h8eixrXcgTXEV6KBA7KPoF DoKWktid555t6jj2+oiwnAV3gQN1Tn9wZnRx9UJE= Subject: FAILED: patch "[PATCH] rust: rust_is_available: warn for `bindgen` < 0.72.1 &&" failed to apply to 6.18-stable tree To: ojeda@kernel.org,burak.emir@gmail.com Cc: From: Date: Thu, 03 Sep 2026 12:43:02 +0200 Message-ID: <2026090302-mumbo-scorebook-4564@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y git checkout FETCH_HEAD git cherry-pick -x dc01dfb37b34beeefcfe1c3055364d41a4070c7e # git commit -s git send-email --to '' --in-reply-to '2026090302-mumbo-scorebook-4564@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From dc01dfb37b34beeefcfe1c3055364d41a4070c7e Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 19 Jul 2026 14:05:14 +0200 Subject: [PATCH] rust: rust_is_available: warn for `bindgen` < 0.72.1 && libclang >= 22 Starting with LLVM 22, `clang_getTypeDeclaration()` may return a forward declaration instead of the type definition. This made `bindgen` generate opaque types [1][2], which in turn made us fail with e.g. error[E0609]: no field `__bindgen_anon_1` on type `bindings::kernel_param` --> rust/kernel/module_param.rs:78:46 | 78 | let container = unsafe { &*((*param).__bindgen_anon_1.arg.cast::>()) }; | ^^^^^^^^^^^^^^^^ unknown field | = note: available field is: `_address` This was fixed in `bindgen` 0.72.1 [3]. In order to clarify what is going on and avoid confusion [4][5], add a warning to `rust_is_available.sh` about it when the versions match, similar to past warnings like the one removed in: commit ae64324ad5c1 ("rust: rust_is_available: remove warning for `bindgen` < 0.69.5 && libclang >= 19.1") In addition, even if the versions match, check if the issue appears to not reproduce with the given binaries, to avoid a warning in such a case. Finally, include tests. [ Nathan, in parallel, updated the instructions of the LLVM+Rust kernel.org toolchains [6] so that `--version` is not passed to `cargo` for `bindgen`, and thus the latest `bindgen` is installed by default, which should help to avoid some of these situations. Thanks! - Miguel ] Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs). Link: https://github.com/rust-lang/rust-bindgen/issues/3264 [1] Link: https://github.com/Rust-for-Linux/linux/issues/353 [2] # "Missing fields in nested class with LLVM 22." Link: https://github.com/rust-lang/rust-bindgen/pull/3278 [3] Reported-by: Burak Emir Link: https://github.com/Rust-for-Linux/linux/issues/1247 [4] Link: https://lore.kernel.org/rust-for-linux/CABwQupNfMAJOGqRM9ke6tj4f53dCCsBDKU7Vp+zf8mwk7bqt8Q@mail.gmail.com/ [5] Link: https://mirrors.edge.kernel.org/pub/tools/llvm/rust/ [6] Tested-by: Burak Emir Link: https://patch.msgid.link/20260719120514.159914-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh index 551f1ebd0dcb..c30983562a2f 100755 --- a/scripts/rust_is_available.sh +++ b/scripts/rust_is_available.sh @@ -208,6 +208,20 @@ if [ "$bindgen_libclang_cversion" -lt "$bindgen_libclang_min_cversion" ]; then exit 1 fi +if [ "$bindgen_libclang_cversion" -ge 2200000 ] && + [ "$rust_bindings_generator_cversion" -lt 7201 ]; then + # Distributions may have patched the issue. + if ! "$BINDGEN" $(dirname $0)/rust_is_available_bindgen_libclang_22.h | grep -q 'pub foo'; then + echo >&2 "***" + echo >&2 "*** Rust bindings generator '$BINDGEN' < 0.72.1 together with libclang >= 22" + echo >&2 "*** may not work due to a bug (https://github.com/rust-lang/rust-bindgen/pull/3278)." + echo >&2 "*** Your bindgen version: $rust_bindings_generator_version" + echo >&2 "*** Your libclang version: $bindgen_libclang_version" + echo >&2 "***" + warning=1 + fi +fi + # If the C compiler is Clang, then we can also check whether its version # matches the `libclang` version used by the Rust bindings generator. # diff --git a/scripts/rust_is_available_bindgen_libclang_22.h b/scripts/rust_is_available_bindgen_libclang_22.h new file mode 100644 index 000000000000..6b33544c14a8 --- /dev/null +++ b/scripts/rust_is_available_bindgen_libclang_22.h @@ -0,0 +1,5 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +struct S; +struct S { + int foo; +}; diff --git a/scripts/rust_is_available_test.py b/scripts/rust_is_available_test.py index b205d792550d..22bdff980c35 100755 --- a/scripts/rust_is_available_test.py +++ b/scripts/rust_is_available_test.py @@ -54,16 +54,23 @@ else: """) @classmethod - def generate_bindgen(cls, version_stdout, libclang_stderr): + def generate_bindgen(cls, version_stdout, libclang_stderr, libclang_22_patched=False): if libclang_stderr is None: libclang_case = f"raise SystemExit({cls.bindgen_default_bindgen_libclang_failure_exit_code})" else: libclang_case = f"print({repr(libclang_stderr)}, file=sys.stderr)" + if libclang_22_patched: + libclang_22_case = "print('pub foo: ::std::os::raw::c_int,')" + else: + libclang_22_case = "pass" + return cls.generate_executable(f"""#!/usr/bin/env python3 import sys if "rust_is_available_bindgen_libclang.h" in " ".join(sys.argv): {libclang_case} +elif "rust_is_available_bindgen_libclang_22.h" in " ".join(sys.argv): + {libclang_22_case} else: print({repr(version_stdout)}) """) @@ -260,6 +267,27 @@ else: result = self.run_script(self.Expected.FAILURE, { "BINDGEN": bindgen }) self.assertIn(f"libclang (used by the Rust bindings generator '{bindgen}') is too old.", result.stderr) + def test_bindgen_bad_libclang_22(self): + for (bindgen_version, libclang_version, expected_not_patched) in ( + ("0.71.1", "21.1.0", self.Expected.SUCCESS), + ("0.71.1", "22.0.0", self.Expected.SUCCESS_WITH_WARNINGS), + ("0.71.1", "22.1.0", self.Expected.SUCCESS_WITH_WARNINGS), + + ("0.72.0", "22.0.0", self.Expected.SUCCESS_WITH_WARNINGS), + + ("0.72.1", "22.0.0", self.Expected.SUCCESS), + ): + with self.subTest(bindgen_version=bindgen_version, libclang_version=libclang_version): + cc = self.generate_clang(f"clang version {libclang_version}") + libclang_stderr = f"scripts/rust_is_available_bindgen_libclang.h:2:9: warning: clang version {libclang_version} [-W#pragma-messages], err: false" + bindgen = self.generate_bindgen(f"bindgen {bindgen_version}", libclang_stderr) + result = self.run_script(expected_not_patched, { "BINDGEN": bindgen, "CC": cc }) + if expected_not_patched == self.Expected.SUCCESS_WITH_WARNINGS: + self.assertIn(f"Rust bindings generator '{bindgen}' < 0.72.1 together with libclang >= 22", result.stderr) + + bindgen = self.generate_bindgen(f"bindgen {bindgen_version}", libclang_stderr, libclang_22_patched=True) + result = self.run_script(self.Expected.SUCCESS, { "BINDGEN": bindgen, "CC": cc }) + def test_clang_matches_bindgen_libclang_different_bindgen(self): bindgen = self.generate_bindgen_libclang("scripts/rust_is_available_bindgen_libclang.h:2:9: warning: clang version 999.0.0 [-W#pragma-messages], err: false") result = self.run_script(self.Expected.SUCCESS_WITH_WARNINGS, { "BINDGEN": bindgen })