Re: [PATCH 3/7] gpu: nova-core: gsp: add checking oversized commands

["Eliot Courtney" <ecourtney@nvidia.com>]

On Wed Feb 18, 2026 at 12:23 PM JST, Alexandre Courbot wrote:
>> +/// Maximum size of a single GSP command in bytes.
>> +///
>> +/// A single command can span up to 16 GSP pages.
>> +pub(crate) const MSGQ_MSG_SIZE_MAX: usize = GSP_PAGE_SIZE * 16;
>
> Where does this limitation come from? Is there a value in OpenRM that we
> can add to the bindings as the source of truth?

This is a GSP protocol level limitation. And yes, there's a constant
so I'll add that to the bindings. Thanks!

>
>> +
>>  /// Circular buffer of a [`Msgq`].
>>  ///
>>  /// This area of memory is to be shared between the driver and the GSP to exchange commands or
>> @@ -329,8 +334,11 @@ fn allocate_command(&mut self, size: usize) -> Result<GspCommand<'_>> {
>>      /// # Errors
>>      ///
>>      /// - `ETIMEDOUT` if space does not become available within the timeout.
>> -    /// - `EIO` if the command header is not properly aligned.
>> +    /// - `EIO` if the command header is not properly aligned or sizing is impossible.
>
> `sizing is impossible` should be its own error - probably `EMSGSIZE`
> (which would need to be added to `kernel/error.rs` in its own patch).
> Also the wording sounds a bit confusing to me, why not say "if the
> command is larger than `MSGQ_MSG_SIZE_MAX`"?

Do you mean in its own patch in this series, or sent as a separate patch
to a different tree (e.g. rfl)?

Tangential but I feel like some of the errors in this file are a bit
odd, like the existing EIO if the command doesn't fit (which it always
should). WDYT?