Steam Deck is getting a fix for serious Zenbleed security flaw - but some gamers are worried

The Steam Deck's engine, a Zen 2 APU, is vulnerable to the Zenbleed exploit - but a fix is now inbound (and a 'fallback' solution is activate for now).

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The engine of the Steam Deck is a custom 'APU 0405' (toting Zen 2 and RDNA 2), and that particular chip was missed off the list for patching up when it came to the Linux kernel.

This is being swiftly remedied, as per a commit Gaming on Linux spotted (via Windows Central), which reads as follows:

"Commit 522b1d69219d ('x86/cpu/amd: Add a Zenbleed fix') provided a fix for the Zen2 VZEROUPPER data corruption bug affecting a range of CPU models, but the AMD Custom APU 0405 found on SteamDeck was not listed, although it is clearly affected by the vulnerability."

"Add this CPU variant to the Zenbleed erratum list, in order to unconditionally enable the fallback fix until a proper microcode update is available."

As that statement notes, the CPU now gets the fallback fix enabled until the full microcode update is pushed out to Steam Deck devices.

This has caused some debate, because the Steam Deck is a gaming device - and these microcode patches can come with caveats in terms of dents in performance, which obviously isn't good news for gamers.

On the other hand, because the Steam Deck is essentially a handheld PC, and can be equipped with a browser - with users going online and potentially being exposed to Zenbleed - to leave it unpatched is a precarious situation, security-wise.

As long as any performance hit is relatively minimal, the safe path is likely the best route to take.