Handle interception of the CHSC SEI instruction for requests
indicating the guest's AP configuration has changed.
If configuring --without-default-devices, hw/s390x/ap-stub.c
was created to handle such circumstance. Also added the
following to hw/s390x/meson.build if CONFIG_VFIO_AP is
false, it will use the stub file.
Signed-off-by: Rorie Reyes <rreyes@linux.ibm.com>
Reviewed-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
---
MAINTAINERS | 1 +
hw/s390x/ap-stub.c | 25 +++++++++++++++++++++++++
hw/s390x/meson.build | 1 +
target/s390x/ioinst.c | 11 +++++++++--
4 files changed, 36 insertions(+), 2 deletions(-)
create mode 100644 hw/s390x/ap-stub.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 7060cf49b9..444523a35e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -112,6 +112,7 @@ F: hw/intc/s390_flic.c
F: hw/intc/s390_flic_kvm.c
F: hw/s390x/
F: hw/vfio/ap.c
+F: hw/s390x/ap-stub.c
F: hw/vfio/ccw.c
F: hw/watchdog/wdt_diag288.c
F: include/hw/s390x/
diff --git a/hw/s390x/ap-stub.c b/hw/s390x/ap-stub.c
new file mode 100644
index 0000000000..e2dacff959
--- /dev/null
+++ b/hw/s390x/ap-stub.c
@@ -0,0 +1,25 @@
+/*
+ * VFIO based AP matrix device assignment
+ *
+ * Copyright 2025 IBM Corp.
+ * Author(s): Rorie Reyes <rreyes@linux.ibm.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/s390x/ap-bridge.h"
+
+int ap_chsc_sei_nt0_get_event(void *res)
+{
+ return 0;
+}
+
+int ap_chsc_sei_nt0_have_event(void)
+{
+ return 0;
+}
diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build
index 3bbebfd817..99cbcbd7d6 100644
--- a/hw/s390x/meson.build
+++ b/hw/s390x/meson.build
@@ -33,6 +33,7 @@ s390x_ss.add(when: 'CONFIG_S390_CCW_VIRTIO', if_true: files(
))
s390x_ss.add(when: 'CONFIG_TERMINAL3270', if_true: files('3270-ccw.c'))
s390x_ss.add(when: 'CONFIG_VFIO', if_true: files('s390-pci-vfio.c'))
+s390x_ss.add(when: 'CONFIG_VFIO_AP', if_false: files('ap-stub.c'))
virtio_ss = ss.source_set()
virtio_ss.add(files('virtio-ccw.c'))
diff --git a/target/s390x/ioinst.c b/target/s390x/ioinst.c
index fe62ba5b06..2320dd4c12 100644
--- a/target/s390x/ioinst.c
+++ b/target/s390x/ioinst.c
@@ -18,6 +18,7 @@
#include "trace.h"
#include "hw/s390x/s390-pci-bus.h"
#include "target/s390x/kvm/pv.h"
+#include "hw/s390x/ap-bridge.h"
/* All I/O instructions but chsc use the s format */
static uint64_t get_address_from_regs(CPUS390XState *env, uint32_t ipb,
@@ -574,13 +575,19 @@ out:
static int chsc_sei_nt0_get_event(void *res)
{
- /* no events yet */
+ if (s390_has_feat(S390_FEAT_AP)) {
+ return ap_chsc_sei_nt0_get_event(res);
+ }
+
return 1;
}
static int chsc_sei_nt0_have_event(void)
{
- /* no events yet */
+ if (s390_has_feat(S390_FEAT_AP)) {
+ return ap_chsc_sei_nt0_have_event();
+ }
+
return 0;
}
--
2.48.1
On 5/23/25 12:47 AM, Rorie Reyes wrote:
> Handle interception of the CHSC SEI instruction for requests
> indicating the guest's AP configuration has changed.
>
> If configuring --without-default-devices, hw/s390x/ap-stub.c
> was created to handle such circumstance. Also added the
> following to hw/s390x/meson.build if CONFIG_VFIO_AP is
> false, it will use the stub file.
>
> Signed-off-by: Rorie Reyes <rreyes@linux.ibm.com>
> Reviewed-by: Anthony Krowiak <akrowiak@linux.ibm.com>
> Reviewed-by: Cédric Le Goater <clg@redhat.com>
> ---
> MAINTAINERS | 1 +
> hw/s390x/ap-stub.c | 25 +++++++++++++++++++++++++
> hw/s390x/meson.build | 1 +
> target/s390x/ioinst.c | 11 +++++++++--
> 4 files changed, 36 insertions(+), 2 deletions(-)
> create mode 100644 hw/s390x/ap-stub.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7060cf49b9..444523a35e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -112,6 +112,7 @@ F: hw/intc/s390_flic.c
> F: hw/intc/s390_flic_kvm.c
> F: hw/s390x/
> F: hw/vfio/ap.c
> +F: hw/s390x/ap-stub.c
> F: hw/vfio/ccw.c
> F: hw/watchdog/wdt_diag288.c
> F: include/hw/s390x/
> diff --git a/hw/s390x/ap-stub.c b/hw/s390x/ap-stub.c
> new file mode 100644
> index 0000000000..e2dacff959
> --- /dev/null
> +++ b/hw/s390x/ap-stub.c
> @@ -0,0 +1,25 @@
> +/*
> + * VFIO based AP matrix device assignment
> + *
> + * Copyright 2025 IBM Corp.
> + * Author(s): Rorie Reyes <rreyes@linux.ibm.com>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or (at
> + * your option) any later version. See the COPYING file in the top-level
> + * directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "hw/s390x/ap-bridge.h"
> +
> +int ap_chsc_sei_nt0_get_event(void *res)
> +{
> + return 0;
> +}
> +
> +int ap_chsc_sei_nt0_have_event(void)
> +{
> + return 0;
> +}
Shouldn't these stub function signatures match those in
ap-bridge.h?
> diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build
> index 3bbebfd817..99cbcbd7d6 100644
> --- a/hw/s390x/meson.build
> +++ b/hw/s390x/meson.build
> @@ -33,6 +33,7 @@ s390x_ss.add(when: 'CONFIG_S390_CCW_VIRTIO', if_true: files(
> ))
> s390x_ss.add(when: 'CONFIG_TERMINAL3270', if_true: files('3270-ccw.c'))
> s390x_ss.add(when: 'CONFIG_VFIO', if_true: files('s390-pci-vfio.c'))
> +s390x_ss.add(when: 'CONFIG_VFIO_AP', if_false: files('ap-stub.c'))
>
> virtio_ss = ss.source_set()
> virtio_ss.add(files('virtio-ccw.c'))
> diff --git a/target/s390x/ioinst.c b/target/s390x/ioinst.c
> index fe62ba5b06..2320dd4c12 100644
> --- a/target/s390x/ioinst.c
> +++ b/target/s390x/ioinst.c
> @@ -18,6 +18,7 @@
> #include "trace.h"
> #include "hw/s390x/s390-pci-bus.h"
> #include "target/s390x/kvm/pv.h"
> +#include "hw/s390x/ap-bridge.h"
>
> /* All I/O instructions but chsc use the s format */
> static uint64_t get_address_from_regs(CPUS390XState *env, uint32_t ipb,
> @@ -574,13 +575,19 @@ out:
>
> static int chsc_sei_nt0_get_event(void *res)
> {
> - /* no events yet */
> + if (s390_has_feat(S390_FEAT_AP)) {
> + return ap_chsc_sei_nt0_get_event(res);
> + }
> +
> return 1;
> }
>
> static int chsc_sei_nt0_have_event(void)
> {
> - /* no events yet */
> + if (s390_has_feat(S390_FEAT_AP)) {
> + return ap_chsc_sei_nt0_have_event();
> + }
> +
> return 0;
> }
>
>> diff --git a/hw/s390x/ap-stub.c b/hw/s390x/ap-stub.c
>> new file mode 100644
>> index 0000000000..e2dacff959
>> --- /dev/null
>> +++ b/hw/s390x/ap-stub.c
>> @@ -0,0 +1,25 @@
>> +/*
>> + * VFIO based AP matrix device assignment
>> + *
>> + * Copyright 2025 IBM Corp.
>> + * Author(s): Rorie Reyes <rreyes@linux.ibm.com>
>> + *
>> + * SPDX-License-Identifier: GPL-2.0-or-later
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2
>> or (at
>> + * your option) any later version. See the COPYING file in the
>> top-level
>> + * directory.
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "hw/s390x/ap-bridge.h"
>> +
>> +int ap_chsc_sei_nt0_get_event(void *res)
>> +{
>> + return 0;
>> +}
>> +
>> +int ap_chsc_sei_nt0_have_event(void)
>> +{
>> + return 0;
>> +}
>
> Shouldn't these stub function signatures match those in
> ap-bridge.h?
>
I'll update 'ap_chsc_sei_nt0_have_event' to be a boolean function, but
keep the get_event as an int. The definition that I'll use from the
header file will keep the integrity of function type
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