impl<H> Iterator for SdtHeaderIterator<'_, H>
where
    H: AcpiHandler,
{
    type Item = SdtHeader;

    fn next(&mut self) -> Option<Self::Item> {
        // ...

        // SAFETY: `address` needs to be valid for the size of `SdtHeader`, or the ACPI tables are malformed (not a
        // software issue).
        let header_mapping = unsafe {
            self.handler.map_physical_region::<SdtHeader>(table_phys_ptr as usize, mem::size_of::<SdtHeader>())
        };
        let r = header_mapping.validate(header_mapping.signature);

        // ...
    }
}

pub fn validate(&self, signature: Signature) -> AcpiResult<()> {
    self.validate_header_fields(signature)?;
    self.validate_checksum(signature)?;

    Ok(())
}

fn validate_checksum(&self, signature: Signature) -> AcpiResult<()> {
        // SAFETY: Entire table is mapped.
        let table_bytes =
            unsafe { core::slice::from_raw_parts((self as *const SdtHeader).cast::<u8>(), self.length as usize) };
        // ...
}