Re: [PATCH 0/4] Improve soundness of bus device abstractions

[Boqun Feng]

On Thu, Mar 13, 2025 at 03:13:30AM +0100, Danilo Krummrich wrote:
> Currently, when sharing references of bus devices (e.g. ARef<pci::Device>), we
> do not have a way to restrict which functions of a bus device can be called.
> 
> Consequently, it is possible to call all bus device functions concurrently from
> any context. This includes functions, which access fields of the (bus) device,
> which are not protected against concurrent access.
> 
> This is improved by applying an execution context to the bus device in form of a
> generic type.
> 
> For instance, the PCI device reference that is passed to probe() has the type
> pci::Device<Core>, which implements all functions that are only allowed to be
> called from bus callbacks.
> 
> The implementation for the default context (pci::Device) contains all functions
> that are safe to call from any context concurrently.
> 
> The context types can be extended as required, e.g. to limit availability  of
> certain (bus) device functions to probe().
> 

For the whole series:

Acked-by: Boqun Feng <boqun.feng@xxxxxxxxx>

Regards,
Boqun

> A branch containing the patches can be found in [1].
> 
> [1] https://web.git.kernel.org/pub/scm/linux/kernel/git/dakr/linux.git/log/?h=rust/device
> 
> Danilo Krummrich (4):
>   rust: pci: use to_result() in enable_device_mem()
>   rust: device: implement device context marker
>   rust: pci: fix unrestricted &mut pci::Device
>   rust: platform: fix unrestricted &mut platform::Device
> 
>  drivers/gpu/nova-core/driver.rs      |   4 +-
>  rust/kernel/device.rs                |  18 ++++
>  rust/kernel/pci.rs                   | 131 ++++++++++++++++-----------
>  rust/kernel/platform.rs              |  93 ++++++++++++-------
>  samples/rust/rust_driver_pci.rs      |   8 +-
>  samples/rust/rust_driver_platform.rs |  16 +++-
>  6 files changed, 177 insertions(+), 93 deletions(-)
> 
> 
> base-commit: b28786b190d1ae2df5e6a5181ad78c6f226ea3e1
> -- 
> 2.48.1
>