On 19/01/2022 13.46, Christian Borntraeger wrote:
Am 19.01.22 um 12:52 schrieb Thomas Huth:
On 18/01/2022 10.52, Janis Schoetterl-Glausch wrote:
Channel I/O honors storage keys and is performed on absolute memory.
For I/O emulation user space therefore needs to be able to do key
checked accesses.
Can't we do the checking in userspace? We already have functions for
handling the storage keys there (see hw/s390x/s390-skeys-kvm.c), so why
can't we do the checking in QEMU?
That would separate the key check from the memory operation. Potentially for
a long time.
Wenn we piggy back on access_guest_abs_with_key we use mvcos in the host and
thus do the key check in lockstep with the keycheck which is the preferrable
solution.
Ok, makes sense - Janis, could you please add this rationale to the patch
description?
Thomas