Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [High] Using `Region<SIZE>` for `IoMem` and `pci::Bar` breaks I/O mappings for valid resources with non-4-byte alignment or odd sizes. --
commit ac5441d891df2073c7c58a81916e6a7310f48450 Author: Gary Guo <[email protected]> rust: io: generalize `MmioRaw` to pointer to arbitrary type This commit updates MmioRaw to be generic over the type it points to. It introduces MmioRaw::new_region utilizing the Region type and updates IoMem and pci::Bar to use this new region API instead of the raw address. > diff --git a/rust/kernel/io.rs b/rust/kernel/io.rs > index 9f060dd291826..12be266d7ed7e 100644 > --- a/rust/kernel/io.rs > +++ b/rust/kernel/io.rs [ ... ] > +impl<const SIZE: usize> MmioRaw<Region<SIZE>> { > + /// Create a `MmioRaw` representing a I/O region with given size. > + /// > + /// The size is checked against the minimum size specified via const > generics. > + #[inline] > + pub fn new_region(addr: usize, size: usize) -> Result<Self> { > + Ok(Self { > + ptr: > Region::ptr_try_from_raw_parts_mut(core::ptr::without_provenance_mut(addr), > size)?, [Severity: High] Does this change prevent drivers from mapping valid hardware resources that are not 4-byte aligned or have sizes that aren't multiples of 4? Looking at Region::ptr_try_from_raw_parts_mut(), it enforces strict alignment and size constraints: if size < SIZE || base.align_offset(4) != 0 || !size.is_multiple_of(4) { return Err(EINVAL); } Since IoMem::ioremap() and pci::Bar::new() now both call MmioRaw::new_region() instead of MmioRaw::new(), wouldn't this cause device probes to unconditionally fail for drivers attempting to map legacy 8-bit or 16-bit peripherals where the I/O resources are not strictly 4-byte aligned or sized? > + }) > + } > +} [ ... ] > diff --git a/rust/kernel/io/mem.rs b/rust/kernel/io/mem.rs > index fc2a3e24f8d5d..9e15bc8fde784 100644 > --- a/rust/kernel/io/mem.rs > +++ b/rust/kernel/io/mem.rs [ ... ] > @@ -264,8 +264,7 @@ fn ioremap(dev: &'a Device<Bound>, resource: &Resource) > -> Result<Self> { > return Err(ENOMEM); > } > > - let io = MmioRaw::new(addr as usize, size)?; > - > + let io = MmioRaw::new_region(addr as usize, size)?; > Ok(IoMem { dev, io }) > } > -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=5
