Re: [PATCH v5 12/13] gpu: nova-core: gsp: separate context and GPU lifetimes in GspBootContext

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The GspSequencer struct was not updated with separate context and GPU lifetimes, leaving it vulnerable to the exact covariance issue this commit aims to fix.
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--- Patch [12]: [PATCH v5 12/13] gpu: nova-core: gsp: separate context and GPU lifetimes in GspBootContext ---
commit 25c80f140498d9178aab39d3a011facb7416a203
Author: Alexandre Courbot <acourbot@nvidia.com>

gpu: nova-core: gsp: separate context and GPU lifetimes in GspBootContext

This commit splits the lifetimes in GspBootContext into separate context and
GPU lifetimes to allow mutable references to GPU subdevices. This distinction
prepares the context for holding mutable borrows of Falcon instances.

> diff --git a/drivers/gpu/nova-core/gsp/sequencer.rs b/drivers/gpu/nova-core/gsp/sequencer.rs
> index ddce32cc4e308..422a74f9ecbd5 100644
> --- a/drivers/gpu/nova-core/gsp/sequencer.rs
> +++ b/drivers/gpu/nova-core/gsp/sequencer.rs
[ ... ]
> @@ -335,7 +335,7 @@ fn next(&mut self) -> Option<Self::Item> {
>  impl<'a> GspSequencer<'a> {

[Severity: Low]
Should GspSequencer also be updated to use separate 'ctx and 'gpu lifetimes?

The commit splits lifetimes in GspBootContext because holding mutable
references to GPU subdevices requires invariant lifetimes. However, the
GspSequencer struct definition still uses a single lifetime for its Falcon
references:

pub(crate) struct GspSequencer<'a> {
    bar: Bar0<'a>,
    sec2_falcon: &'a Falcon<'a, Sec2>,
    gsp_falcon: &'a Falcon<'a, Gsp>,
    ...

Will this cause similar compilation errors for GspSequencer when the Falcon
references are eventually made mutable?

>      pub(crate) fn run(
>          cmdq: &Cmdq,
> -        ctx: &'a GspBootContext<'_>,
> +        ctx: &'a GspBootContext<'_, '_>,
>          libos_dma_handle: u64,
>          bootloader_app_version: u32,
>      ) -> Result {

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260707-nova-bootcontext-v5-0-ecad9346387f@nvidia.com?part=12