Re: [PATCH] rust: pci: fix build failure when CONFIG_PCI_MSI is disabled

[Alice Ryhl]

On Wed, Dec 03, 2025 at 10:01:50AM +1300, Danilo Krummrich wrote:
> When CONFIG_PCI_MSI is disabled pci_alloc_irq_vectors() and
> pci_free_irq_vectors() are defined as inline functions and hence require
> a Rust helper.
> 
> 	error[E0425]: cannot find function `pci_alloc_irq_vectors` in crate `bindings`
> 	    --> rust/kernel/pci/irq.rs:144:23
> 	     |
> 	 144 | ...s::pci_alloc_irq_vectors(dev.as_raw(), min_vecs, max_vecs, irq_types.as_raw())
> 	     |       ^^^^^^^^^^^^^^^^^^^^^ help: a function with a similar name exists: `pci_irq_vector`
> 	     |
> 	    ::: .../rust/bindings/bindings_helpers_generated.rs:1197:5
> 	     |
> 	1197 |     pub fn pci_irq_vector(pdev: *mut pci_dev, nvec: ffi::c_uint) -> ffi::c_int;
> 	     |     --------------------------------------------------------------------------- similarly named function `pci_irq_vector` defined here
> 
> 	error[E0425]: cannot find function `pci_free_irq_vectors` in crate `bindings`
> 	    --> rust/kernel/pci/irq.rs:170:28
> 	     |
> 	 170 |         unsafe { bindings::pci_free_irq_vectors(self.dev.as_raw()) };
> 	     |                            ^^^^^^^^^^^^^^^^^^^^ help: a function with a similar name exists: `pci_irq_vector`
> 	     |
> 	    ::: .../rust/bindings/bindings_helpers_generated.rs:1197:5
> 	     |
> 	1197 |     pub fn pci_irq_vector(pdev: *mut pci_dev, nvec: ffi::c_uint) -> ffi::c_int;
> 	     |     --------------------------------------------------------------------------- similarly named function `pci_irq_vector` defined here
> 
> 	error: aborting due to 2 previous errors
> 
> Fix this by adding the corresponding helpers.
> 
> Fixes: 340ccc973544 ("rust: pci: Allocate and manage PCI interrupt vectors")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202512012238.YgVvRRUx-lkp@xxxxxxxxx/
> Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>

It may make sense to add __rust_helper to these helpers right away.

otherwise:
Reviewed-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>

Alice

For context:
https://lore.kernel.org/all/20251202-define-rust-helper-v1-0-a2e13cbc17a6@xxxxxxxxxx/