In 32-bit arm, the build fails with: error[E0308]: mismatched types --> drivers/gpu/drm/nova/file.rs:42:28 | 42 | getparam.set_value(value); | --------- ^^^^^ expected `u64`, found `u32` | | | arguments to this method are incorrect | note: method defined here --> drivers/gpu/drm/nova/uapi.rs:29:12 | 29 | pub fn set_value(&self, v: u64) { | ^^^^^^^^^ ------ help: you can convert a `u32` to a `u64` | 42 | getparam.set_value(value.into()); | +++++++ The reason is that `Getparam::set_value` takes a `u64` (from the UAPI), but `pci::Device::resource_len()` returns a `resource_size_t`, which is a `phys_addr_t`, which may be 32- or 64-bit. Thus add an `into()` call to support the 32-bit case, while allowing the Clippy lint that complains in the 64-bit case where the type is the same. Fixes: cdeaeb9dd762 ("drm: nova-drm: add initial driver skeleton") Signed-off-by: Miguel Ojeda <ojeda at kernel.org> --- As discussed, it may be best to have a newtype, or at least a function to perform this -- here it is the minimal fix nevertheless. drivers/gpu/drm/nova/file.rs | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nova/file.rs b/drivers/gpu/drm/nova/file.rs index 7e59a34b830d..4fe62cf98a23 100644 --- a/drivers/gpu/drm/nova/file.rs +++ b/drivers/gpu/drm/nova/file.rs @@ -39,7 +39,8 @@ pub(crate) fn get_param( _ => return Err(EINVAL), }; - getparam.set_value(value); + #[allow(clippy::useless_conversion)] + getparam.set_value(value.into()); Ok(0) } base-commit: 89be9a83ccf1f88522317ce02f854f30d6115c41 -- 2.50.1
On Thu Jul 24, 2025 at 6:54 PM CEST, Miguel Ojeda wrote:> In 32-bit arm, the build fails with: > > error[E0308]: mismatched types > --> drivers/gpu/drm/nova/file.rs:42:28 > | > 42 | getparam.set_value(value); > | --------- ^^^^^ expected `u64`, found `u32` > | | > | arguments to this method are incorrect > | > note: method defined here > --> drivers/gpu/drm/nova/uapi.rs:29:12 > | > 29 | pub fn set_value(&self, v: u64) { > | ^^^^^^^^^ ------ > help: you can convert a `u32` to a `u64` > | > 42 | getparam.set_value(value.into()); > | +++++++ > > The reason is that `Getparam::set_value` takes a `u64` (from the UAPI), > but `pci::Device::resource_len()` returns a `resource_size_t`, which is a > `phys_addr_t`, which may be 32- or 64-bit. > > Thus add an `into()` call to support the 32-bit case, while allowing the > Clippy lint that complains in the 64-bit case where the type is the same. > > Fixes: cdeaeb9dd762 ("drm: nova-drm: add initial driver skeleton") > Signed-off-by: Miguel Ojeda <ojeda at kernel.org>Thanks -- will take it through -fixes once rc-1 is out.> --- > As discussed, it may be best to have a newtype, or at least a function > to perform this -- here it is the minimal fix nevertheless.I think I will follow up with a function to perform the conversion in a single place, but I really like the idea of a special clippy annotation to tell clippy to not warn about unnecessary into() conversions for a specific type alias, such as ResourceSize. Do we agree that we want something like this? Do we even have a feature request for this already?
On 7/24/25 6:54 PM, Miguel Ojeda wrote:> In 32-bit arm, the build fails with: > > error[E0308]: mismatched types > --> drivers/gpu/drm/nova/file.rs:42:28 > | > 42 | getparam.set_value(value); > | --------- ^^^^^ expected `u64`, found `u32` > | | > | arguments to this method are incorrect > | > note: method defined here > --> drivers/gpu/drm/nova/uapi.rs:29:12 > | > 29 | pub fn set_value(&self, v: u64) { > | ^^^^^^^^^ ------ > help: you can convert a `u32` to a `u64` > | > 42 | getparam.set_value(value.into()); > | +++++++ > > The reason is that `Getparam::set_value` takes a `u64` (from the UAPI), > but `pci::Device::resource_len()` returns a `resource_size_t`, which is a > `phys_addr_t`, which may be 32- or 64-bit. > > Thus add an `into()` call to support the 32-bit case, while allowing the > Clippy lint that complains in the 64-bit case where the type is the same. > > Fixes: cdeaeb9dd762 ("drm: nova-drm: add initial driver skeleton") > Signed-off-by: Miguel Ojeda <ojeda at kernel.org>Applied to drm-misc-fixes, thanks!