Re: [PATCH v5 00/10] KVM: s390: Extend MEM_OP ioctl by storage key checked cmpxchg

[Janosch Frank]

On 1/10/23 21:26, Janis Schoetterl-Glausch wrote:
> User space can use the MEM_OP ioctl to make storage key checked reads
> and writes to the guest, however, it has no way of performing atomic,
> key checked, accesses to the guest.
> Extend the MEM_OP ioctl in order to allow for this, by adding a cmpxchg
> mode. For now, support this mode for absolute accesses only.
>
> This mode can be use, for example, to set the device-state-change
> indicator and the adapter-local-summary indicator atomically.
>
> Also contains some fixes/changes for the memop selftest independent of
> the cmpxchg changes.

Since the selftest fixes seem to apply and run without the new code I'm 
considering splitting them off entirely.

Most of them have reviews already and they are lower risk anyway so we 
could add them to devel rather soonish.