Re: [PATCH v3] hwrng: virtio: clamp device-reported used.len at copy_data()

[Herbert Xu]

On Thu, Jun 11, 2026 at 05:10:32AM -0400, Michael S. Tsirkin wrote:
>
> data_avail is under hypervisor control
> 
>         avail = min_t(unsigned int, vi->data_avail, sizeof(vi->data));
>         if (vi->data_idx >= avail) {
>         	vi->data_idx = 0;
> 
> and maybe this can speculate past the if?
> 
> I agree, this is all speculation )

Either it is vulnerable to Spectre, or it isn't.  Adding nospec
markers when you're not sure is cargo cult programming.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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