Re: [PATCH v2 0/4] Improve soundness of bus device abstractions
From: Greg KH
Date: Sat Mar 15 2025 - 04:35:45 EST
On Fri, Mar 14, 2025 at 05:09:03PM +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().
>
> 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
>
> Changes in v2:
> - make `DeviceContext` trait sealed
> - impl From<&pci::Device<device::Core>> for ARef<pci::Device>
> - impl From<&platform::Device<device::Core>> for ARef<platform::Device>
> - rebase onto v6.14-rc6
> - apply RBs
>
> 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
>
> rust/kernel/device.rs | 26 +++++
> rust/kernel/pci.rs | 137 +++++++++++++++++----------
> rust/kernel/platform.rs | 95 +++++++++++++------
> samples/rust/rust_driver_pci.rs | 8 +-
> samples/rust/rust_driver_platform.rs | 11 ++-
> 5 files changed, 187 insertions(+), 90 deletions(-)
Thanks for doing this work, looks good to me. Mind if I suck it into
the driver-core tree now? Or do you want it to go through a different
tree?
thanks,
greg k-h