https://www.theregister.co.uk/2018/01/12/should_sans_be_patched_to_fix_the_spectre_and_meltdown_bugs_er_yes_and_no/

Analysis Is the performance sapping spectre of the X86 Spectre/Meltdown bug fixes hanging over SAN storage arrays? The general assumption is "yes" but five suppliers say not.

You would expect SANs to need patching; they run their controller software on X86 servers after all.