On Fri, Jul 28, 2023 at 09:28:58AM +0200, Christian Borntraeger wrote: > Am 27.07.23 um 20:29 schrieb Heiko Carstens: > > Commit 9fb6c9b3fea1 ("s390/sthyi: add cache to store hypervisor info") > > added cache handling for store hypervisor info. This also changed the > > possible return code for sthyi_fill(). > > > > Instead of only returning a condition code like the sthyi instruction would > > do, it can now also return a negative error value (-ENOMEM). handle_styhi() > > was not changed accordingly. In case of an error, the negative error value > > would incorrectly injected into the guest PSW. > > > > Add proper error handling to prevent this, and update the comment which > > describes the possible return values of sthyi_fill(). > > To me it looks like this can only happen if page allocation fails? This should > not happen in normal cases (and return -ENOMEM would likely kill the guest as > QEMU would stop). > But if it happens we better stop. Yes, no reason for any stable backports. But things might change in the future, so we better have correct error handling in place.