| Message ID | 20241025141453.1210600-2-david@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | virtio-mem: s390 support | expand |
On Fri, Oct 25, 2024 at 04:14:46PM +0200, David Hildenbrand wrote: > Let's make it a generic KVM hypercall, allowing other subfunctions to > be more independent of virtio. > > While at it, document that unsupported/unimplemented subfunctions result > in a SPECIFICATION exception. > > This is a preparation for documenting a new hypercall. > > Signed-off-by: David Hildenbrand <david@redhat.com> > --- > Documentation/virt/kvm/s390/s390-diag.rst | 18 +++++++++++------- > 1 file changed, 11 insertions(+), 7 deletions(-) Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
On Fri, 2024-10-25 at 16:14 +0200, David Hildenbrand wrote: > Let's make it a generic KVM hypercall, allowing other subfunctions to > be more independent of virtio. > > While at it, document that unsupported/unimplemented subfunctions result > in a SPECIFICATION exception. > > This is a preparation for documenting a new hypercall. s/hypercall/subfunction/ ? > > Signed-off-by: David Hildenbrand <david@redhat.com> > --- > Documentation/virt/kvm/s390/s390-diag.rst | 18 +++++++++++------- > 1 file changed, 11 insertions(+), 7 deletions(-) Reviewed-by: Eric Farman <farman@linux.ibm.com>
On 31.10.24 15:56, Eric Farman wrote: > On Fri, 2024-10-25 at 16:14 +0200, David Hildenbrand wrote: >> Let's make it a generic KVM hypercall, allowing other subfunctions to >> be more independent of virtio. >> >> While at it, document that unsupported/unimplemented subfunctions result >> in a SPECIFICATION exception. >> >> This is a preparation for documenting a new hypercall. > > s/hypercall/subfunction/ ? Indeed, thanks! I assume this can be fixed up when applying, unless I have to resend for other reasons. > >> >> Signed-off-by: David Hildenbrand <david@redhat.com> >> --- >> Documentation/virt/kvm/s390/s390-diag.rst | 18 +++++++++++------- >> 1 file changed, 11 insertions(+), 7 deletions(-) > > Reviewed-by: Eric Farman <farman@linux.ibm.com> > Thanks!
diff --git a/Documentation/virt/kvm/s390/s390-diag.rst b/Documentation/virt/kvm/s390/s390-diag.rst index ca85f030eb0b..48a326d41cc0 100644 --- a/Documentation/virt/kvm/s390/s390-diag.rst +++ b/Documentation/virt/kvm/s390/s390-diag.rst @@ -35,20 +35,24 @@ DIAGNOSE function codes not specific to KVM, please refer to the documentation for the s390 hypervisors defining them. -DIAGNOSE function code 'X'500' - KVM virtio functions ------------------------------------------------------ +DIAGNOSE function code 'X'500' - KVM functions +---------------------------------------------- -If the function code specifies 0x500, various virtio-related functions -are performed. +If the function code specifies 0x500, various KVM-specific functions +are performed, including virtio functions. -General register 1 contains the virtio subfunction code. Supported -virtio subfunctions depend on KVM's userspace. Generally, userspace -provides either s390-virtio (subcodes 0-2) or virtio-ccw (subcode 3). +General register 1 contains the subfunction code. Supported subfunctions +depend on KVM's userspace. Regarding virtio subfunctions, generally +userspace provides either s390-virtio (subcodes 0-2) or virtio-ccw +(subcode 3). Upon completion of the DIAGNOSE instruction, general register 2 contains the function's return code, which is either a return code or a subcode specific value. +If the specified subfunction is not supported, a SPECIFICATION exception +will be triggered. + Subcode 0 - s390-virtio notification and early console printk Handled by userspace.
Let's make it a generic KVM hypercall, allowing other subfunctions to be more independent of virtio. While at it, document that unsupported/unimplemented subfunctions result in a SPECIFICATION exception. This is a preparation for documenting a new hypercall. Signed-off-by: David Hildenbrand <david@redhat.com> --- Documentation/virt/kvm/s390/s390-diag.rst | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-)