Re: [PATCH] rust: zerocopy: update to v0.8.54

["Gary Guo" <gary@garyguo.net>]

On Thu Jul 9, 2026 at 10:13 PM BST, Miguel Ojeda wrote:
> Update our vendored copy of `zerocopy` (and `zerocopy-derive`) to v0.8.54.
> 
> It is a very small delta from v0.8.52, and most importantly it resolves
> the unexpected lack of inlining [1] which triggered a modpost error
> under `CONFIG_CC_OPTIMIZE_FOR_SIZE=y` reported by Alexandre using Gary's
> suggestion [2]:
> 
>     ERROR: modpost: "_RNvMNtCs5wX7wwEUCR9_8zerocopy6layoutNtB2_8SizeInfo24try_to_nonzero_elem_size" [drivers/gpu/nova-core.ko] undefined!
>     ERROR: modpost: "_RNvNtCs5wX7wwEUCR9_8zerocopy4util18padding_needed_for" [drivers/gpu/nova-core.ko] undefined!
> 
> It also resolves `most_traits` being unexpectedly documented [3] that I
> reported and adds a missing SPDX license identifier [4] that I requested
> to match the kernel version.
> 
> The following script may be used to check for the remaining differences:
> 
>     for path in $(cd rust/zerocopy-derive/ && find . -type f ! -name README.md); do
>         curl --silent --show-error --location \
>             https://github.com/google/zerocopy/raw/v0.8.54/zerocopy/zerocopy-derive/src/$path |
>             git diff --no-index - rust/zerocopy-derive/$path &&
>             echo $path: OK
>     done
> 
>     for path in $(cd rust/zerocopy/ && find . -type f ! -name README.md); do
>         curl --silent --show-error --location \
>             https://github.com/google/zerocopy/raw/v0.8.54/zerocopy/$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>
> Reported-by: Alexandre Courbot <acourbot@nvidia.com>
> Link: https://lore.kernel.org/rust-for-linux/20260708-zerocopy-export-v1-1-2bfc355853c6@nvidia.com/ [1]
> Suggested-by: Gary Guo <gary@garyguo.net>
> Link: https://lore.kernel.org/rust-for-linux/DJT6235B3DOV.222XR5O6VHG4M@garyguo.net/ [2]
> Link: https://github.com/google/zerocopy/issues/3466 [3]
> Link: https://github.com/google/zerocopy/issues/3457 [4]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Gary Guo <gary@garyguo.net>

> ---
> This goes on top of the v0.8.52 one:
> 
>   https://lore.kernel.org/rust-for-linux/20260625231919.692444-1-ojeda@kernel.org/
> 
> I may land both in `rust-fixes`, especially if someone else can confirm
> it works for them (I reproduced Alexandre's issue and this does indeed
> solve it).
> 
>  rust/Makefile                   |  2 +-
>  rust/zerocopy-derive/README.md  | 12 ++++++------
>  rust/zerocopy-derive/lib.rs     |  2 +-
>  rust/zerocopy/README.md         | 12 ++++++------
>  rust/zerocopy/rustdoc/style.css |  1 -
>  rust/zerocopy/src/byteorder.rs  |  1 +
>  rust/zerocopy/src/layout.rs     |  2 ++
>  rust/zerocopy/src/lib.rs        |  1 -
>  rust/zerocopy/src/util/mod.rs   |  6 ++++++
>  9 files changed, 23 insertions(+), 16 deletions(-)