On Fri, 2026-01-30 at 08:31 +0000, Alice Ryhl wrote:
> On Wed, Jan 28, 2026 at 08:28:33PM -0600, Timur Tabi wrote:
> > [PATCH v6 3/7] gpu: nova-core: implement BinaryWriter for
> > CoherentAllocation<u8>
>
> The commit title says 'gpu: nova-core:' but this is primarily a change
> to rust/kernel/dma.rs, so it should say 'rust: dma:' or similar.
Ok.
>
> > +// SAFETY: Sharing `&CoherentAllocation` across threads is safe if `T` is
> > `Sync`, because
> > all
> > +// methods that access the buffer contents (`field_read`, `field_write`,
> > `as_slice`,
> > +// `as_slice_mut`) are `unsafe`, and callers are responsible for ensuring
> > no data races
> > occur.
> > +// The safe methods only return metadata or raw pointers whose use
> > requires `unsafe`.
> > +unsafe impl<T: AsBytes + FromBytes + Sync> Sync for CoherentAllocation<T>
> > {}
>
> This change is unrelated to implementing BinaryWriter for
> CoherentAllocation.
Did you intend to reference this diff in gsp.rs?
use kernel::{
+ debugfs,
device,
dma::{
CoherentAllocation,
because that diff was mistakenly added to this commit. However, I'm pretty
sure the `Sync for
CoherentAllocation<T>` should be part of 'implement BinaryWriter for
CoherentAllocation<u8>'
because debugfs::read_binary_file() requires T: BinaryWriter + Sync.
> > +impl debugfs::BinaryWriter for CoherentAllocation<u8> {
> > + fn write_to_slice(
> > + &self,
> > + writer: &mut UserSliceWriter,
> > + offset: &mut file::Offset,
> > + ) -> Result<usize> {
> > + if offset.is_negative() {
> > + return Err(EINVAL);
> > + }
> > +
> > + let offset_val: usize = (*offset).try_into().map_err(|_| EINVAL)?;
>
> If the user seeks to a large offset, this leads to EINVAL. But the
> correct behavior for a file is to simply return Ok(0) in such case.
Will fix in 7. Thanks.
