On Sun, Feb 09, 2020 at 01:37:35PM +0100, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 55680890ea78be0df5e1384989f1be835043c084 Mon Sep 17 00:00:00 2001
From: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Date: Fri, 31 Jan 2020 05:02:00 -0500
Subject: [PATCH] KVM: s390: do not clobber registers during guest reset/store
status
The initial CPU reset clobbers the userspace fpc and the store status
ioctl clobbers the guest acrs + fpr. As these calls are only done via
ioctl (and not via vcpu_run), no CPU context is loaded, so we can (and
must) act directly on the sync regs, not on the thread context.
Cc: stable@xxxxxxxxxx
Fixes: e1788bb995be ("KVM: s390: handle floating point registers in the run ioctl not in vcpu_put/load")
Fixes: 31d8b8d41a7e ("KVM: s390: handle access registers in the run ioctl not in vcpu_put/load")
Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200131100205.74720-2-frankja@xxxxxxxxxxxxx
Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
This was a context conflict because we don't have b9224cd7381a ("KVM:
s390: introduce defines for control registers") on 4.14. I've fixed it
and queued it up on 4.14.
--
Thanks,
Sasha
