Re: [PATCH] KVM: VMX: Formally define KVM's "0xdead" exit reason used for failed VM-Enter

On 9/22/2026 7:56 AM, Sean Christopherson wrote:

Add EXIT_REASON_UNDEFINED to track KVM's magic "0xdead" value that's used
to stuff the exit reason on a failed VM-Enter so that the magic can be
reused by TDX, and to make it more obvious that it's an arbitrary, KVM-
defined value (though the whole "dead" thing makes it pretty darn obvious).

Opportunistically add a compile-time assert to ensure the KVM-defined exit
reason never collides with a "real" exit reason.

No functional change intended.

Cc: Xiaoyao Li <redacted>
Cc: Yan Zhao <redacted>
Cc: Binbin Wu <redacted>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>

Reviewed-by: Xiaoyao Li <redacted>