On 06/02/2026 3:53 pm, [email protected] wrote:
> Abdelkareem Abdelsaamad (3):
> svm/vnmi: introduce the vnmi bit support in the cpuid feature set
> svm/vnmi: add the definitions for the svm vnmi management bits in the
> VMCB
> svm/vnmi: Add support for the SVM Virtual NMI
>
> xen/arch/x86/hvm/hvm.c | 29 +++++++++++++++++++++--------
> xen/arch/x86/hvm/svm/intr.c | 16 ++++++++++++++--
> xen/arch/x86/hvm/svm/svm.c | 25 ++++++++++++++++++++++++-
> xen/arch/x86/hvm/svm/vmcb.c | 3 +++
> xen/arch/x86/hvm/svm/vmcb.h | 12 ++++++++----
> xen/arch/x86/include/asm/hvm/hvm.h | 12 +++++++++++-
> xen/arch/x86/include/asm/hvm/svm.h | 2 ++
> 7 files changed, 83 insertions(+), 16 deletions(-)
Patches 1 and 2 want merging. They're both enumerations and
configuration bits, although the very first hunk of patch 1 (the P())
wants delaying until the final patch; we shouldn't print out the
capability until it's being used.
The patch subjects want to be:
x86/svm: Enumerations for virtual NMI
and
x86/svm: Use virtual NMI when available
Everything here is local to SVM. Notably there should be no edits to
hvm.c or hvm.h. By introducing hvm_intblk_vnmi, you break NMI injection
in other cases. vNMI is just a hardware-optimised way of handling the
hvm_intblk_nmi_iret case.
svm_inject_nmi() wants to gain a check to see whether vNMI is enabled,
and in the case that it is, simply set vnmi_pending. You have this
partially, but it needs to be dependent on the VMCB vNMI setting, not
some global idea of enablement.
svm_get_interrupt_shadow() needs a similar adjustment to read
vnmi_blocked rather than unconditionally depending on INTERCEPT_IRET.
In construct_vmcb(), you need to check cpu_has_svm_vnmi. I think this
change is simple enough to be enabled unconditionally. (We'll need to
change this in due course, but that's going to take other infrastructure
which we don't have yet.)
I think that's everything that needs altering.
A couple of other minor notes:
In the vintr_t union, use an anonymous 3 bit field (literally "u64 :3;",
which is valid syntax) instead of renumbering the rsvd$N fields. That
will shrink the diff.
Xen's style has spaces inside the outermost brackets for control
structures, and {'s on new lines. For the functions you're modifying,
just copy the surrounding style.
~Andrew
