Am 28.07.23 um 11:14 schrieb Heiko Carstens:
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.
Feel free to carry via the s390 tree.
