Update our vendored copy of `zerocopy` (and `zerocopy-derive`) to v0.8.52.
Most SPDX identifiers have been added upstream at our request [1]
(without parentheses -- supporting them is an issue on the kernel side,
but it does already reduce our differences). The CSS one for `rustdoc`
was added too [2], but will be picked up in a later version.
For `zerocopy`, enable `--cfg no_fp_fmt_parse`, which was added at our
request to avoid our local workaround [3]. This means one less difference,
thus indicate so in our `README.md`.
For `zerocopy-derive`, enable `--cfg zerocopy_unstable_linux`. This
allows us to use `#[derive(zerocopy_derive::most_traits)]`, a new feature
upstream added for us [4]. We noticed a minor doc render bug [5], which
will be fixed for a future version too.
The following script may be used to check for the remaining differences:
for path in $(cd rust/zerocopy-derive/ && find . -type f ! -name README.md); do
curl --silent --show-error --location \
https://github.com/google/zerocopy/raw/v0.8.52/zerocopy/zerocopy-derive/src/$path |
git diff --no-index - rust/zerocopy-derive/$path &&
echo $path: OK
done
for path in $(cd rust/zerocopy/ && find . -type f ! -name README.md); do
curl --silent --show-error --location \
https://github.com/google/zerocopy/raw/v0.8.52/zerocopy/$path |
git diff --no-index - rust/zerocopy/$path &&
echo $path: OK
done
Cc: Joshua Liebow-Feeser <joshlf@google.com>
Cc: Jack Wrenn <jswrenn@google.com>
Link: https://github.com/google/zerocopy/issues/3428 [1]
Link: https://github.com/google/zerocopy/issues/3457 [2]
Link: https://github.com/google/zerocopy/issues/3426 [3]
Link: https://github.com/google/zerocopy/pull/3416 [4]
Link: https://github.com/google/zerocopy/issues/3466 [5]
Acked-by: Nicolas Schier <n.schier@fritz.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260625231919.692444-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Linux is built with `-Dnon_ascii_idents`. However, `zerocopy-derive`
uses a non-ASCII character (`ẕ`) internally, which in turn triggers
the lint when attempting to use derives like `FromBytes`:
error: identifier contains non-ASCII characters
--> rust/kernel/lib.rs:153:9
|
153 | a: u32,
| ^
|
= note: requested on the command line with `-D non-ascii-idents`
This was already noticed by another project using
`#![deny(non_ascii_idents)]` [1]. `zerocopy` added an
`#[allow(non_ascii_idents)]` [2], but it does not work since, at the
moment, the `non_ascii_idents` lint is a `crate_level_only` one, and thus
`allow`s only work at the crate root level.
Due to this, an issue about relaxing this restriction was created in
upstream Rust [3] some months ago.
Thus work around it here by using another prefix. The likelihood of a
collision is very small for us, since we control the callers, and this
will hopefully be fixed soon at either the `zerocopy` or the Rust level.
I filed an issue [4] about it with upstream `zerocopy` as requested
and we discussed this with upstream Rust and `zerocopy`: the Rust issue
got nominated and a PR [5] to relax the restriction was submitted by
Joshua. Upstream `zerocopy` prefers that approach, so if Rust merges it,
then it means we will be able to remove the workaround when we bump the
MSRV, thus likely late 2027, since we follow Debian Stable.
Cc: Joshua Liebow-Feeser <joshlf@google.com>
Cc: Jack Wrenn <jswrenn@google.com>
Link: https://github.com/google/zerocopy/issues/2880 [1]
Link: https://github.com/google/zerocopy/pull/2882 [2]
Link: https://github.com/rust-lang/rust/issues/151025 [3]
Link: https://github.com/google/zerocopy/issues/3427 [4]
Link: https://github.com/rust-lang/rust/pull/157497 [5]
Link: https://patch.msgid.link/20260608141439.182634-16-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Originally, when the Rust upstream `alloc` standard library crate was
vendored, the SPDX License Identifiers were added to every file so that
the license on those was clear. The same happened with the vendoring of
`proc_macro2`, `quote` and `syn`. Please see:
commit 057b8d2571 ("rust: adapt `alloc` crate to the kernel")
commit 69942c0a89 ("rust: syn: add SPDX License Identifiers")
commit ddfa1b279d ("rust: quote: add SPDX License Identifiers")
commit a9acfceb96 ("rust: proc-macro2: add SPDX License Identifiers")
Thus do the same for the `zerocopy-derive` crate.
This makes `scripts/spdxcheck.py` pass: use parentheses like commit
06e9bfc1e5 ("ionic: make spdxcheck.py happy") did since we have two
`OR` operators in the expression (three licenses).
Finally, as requested, I filed an issue [1] with upstream about it.
Cc: Joshua Liebow-Feeser <joshlf@google.com>
Cc: Jack Wrenn <jswrenn@google.com>
Link: https://github.com/google/zerocopy/issues/3428 [1]
Link: https://patch.msgid.link/20260608141439.182634-15-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
