Re: [PATCH] efivarfs: Rate limit statfs() handler

On Wed, 19 Aug 2026, at 19:29, Anisse Astier wrote:
> Hi Ard,
>
> I like the new approach, it's much simpler and easier to understand
>
> On Tue, Aug 18, 2026 at 04:11:50PM +0200, Ard Biesheuvel wrote:
>> Ravi reports that statfs() may be called by unprivileged users on the
>> efivarfs mount point, which may result in a flood of calls to the
>> QueryVariableInfo() runtime service. These calls are disproportionately
>> costly on x86 systems where the variable store is backed by SMM, as each
>> SMM entry requires a rendez-vous of all the CPUs.
>> 
>> So rate limit the calls to QueryVariableInfo() at twice per second, and
>
> It's already a high-rate in performance sensitive environment. I'd have
> gone higher at once per 10 seconds for example. But really, this is
> minor, so please consider this:
>
> Reviewed-by: <[email protected]>
>

Thanks!