Re: [PATCH v4 2/5] s390x: switch pv and subsystem reset ordering on reboot

["Marc Hartmayer" <mhartmay@linux.ibm.com>]

On Wed, Aug 23, 2023 at 04:22 PM +0200, Steffen Eiden <seiden@linux.ibm.com> wrote:
> From: Janosch Frank <frankja@linux.ibm.com>
>
> Bound APQNs have to be reset before tearing down the secure config via
> s390_machine_unprotect(). Otherwise the Ultravisor will return a error
> code.
>
> So let's switch the ordering around to make that happen.
>
> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> ---
>  hw/s390x/s390-virtio-ccw.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index 4b36c9970e..795dd53d68 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -442,13 +442,13 @@ static void s390_machine_reset(MachineState *machine, ShutdownCause reason)
>      switch (reset_type) {
>      case S390_RESET_EXTERNAL:
>      case S390_RESET_REIPL:
> +        qemu_devices_reset(reason);
> +        s390_crypto_reset();
> +
>          if (s390_is_pv()) {
>              s390_machine_unprotect(ms);
>          }
>  
> -        qemu_devices_reset(reason);
> -        s390_crypto_reset();
> -
>          /* configure and start the ipl CPU only */
>          run_on_cpu(cs, s390_do_cpu_ipl, RUN_ON_CPU_NULL);
>          break;
> -- 
> 2.41.0
>

Unfortunately, this breaks things for me. You can reproduce the problem
easily… Start an SE guest via direct kernel boot and reboot the guest
after the guest has booted.

e.g.

$ sudo qemu-system-s390x -smp 2 --machine accel=kvm,aes-key-wrap=off -kernel /var/lib/libvirt/images/hades/vmlinux-s390x.se.img -m 2048 -nographic -nodefaults -chardev stdio,id=c1,mux=on  -device sclpconsole,chardev=c1 -append "earlyprintk"
…
#  reboot  # (console in the guest)
…
[    3.966496] systemd-shutdown[1]: Syncing filesystems and block devices.
[    3.966606] systemd-shutdown[1]: Rebooting.
qemu-system-s390x: CPU reset failed on CPU 0 type aec4
qemu-system-s390x: CPU reset failed on CPU 1 type aec4
qemu-system-s390x: KVM PV command 4 (KVM_PV_VERIFY) failed: header rc 102 rrc 1b IOCTL rc: -22
Protected boot has failed: 0xa02

-- 
Kind regards / Beste Grüße
   Marc Hartmayer

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