Re: [PATCH 1/3] irqchip/gic-v3-its: Zero ITS pages before sharing them with the host

[Fuad Tabba]

Hi Suzuki,

On Fri, 06 Nov 2026 14:31:56 +0000, Suzuki K Poulose
<suzuki.poulose@xxxxxxx> wrote:
[...]
> We hit a similar problem with CCA, but not from a security perspective,
> but a functionality perspective (crashing the Realm VM). There was a
> patch proposed here [0]. The general consensus was to fix this for
> all "shared allocations" and Aneesh has (had different attempts at this,
> but the latest) series is here [1]. Do you think something like this
> would be preferred than fixing every caller like this ?
>
> [0] https://lore.kernel.org/all/20260820150034.88729-2-steven.price@xxxxxxx
> [1]
> https://lore.kernel.org/all/20261104164555.3555725-1-aneesh.kumar@xxxxxxxxxx

For mainline, yes. Patch 2 of [1] zeroes the memory inside
set_memory_decrypted(), before the share on pKVM and after the
conversion on CCA, so every caller gets the order its platform
requires.

That said, [1] isn't stable material, so I'd still like this patch to
go in as the stable fix. Patch 4 of [1] would then replace it.

Cheers,
/fuad