KVM: x86: Prioritize DR7.GD #DB over #GP due to illegal DR6/7 value

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When emulating a MOV DR, specifically a write to DR6 or DR7, treat a #DB
due to DR7.GD (General Detect) as higher priority than a #GP due to an
illegal value.  While neither Intel's SDM nor AMD's APM says anything
about the relative priority, empirical testing on Intel and AMD shows that
the #DB has higher priority.  And for VMX, where the instruction intercept
has priority over *all* exceptions, KVM already treats the #DB as having
higher priority.

Cc: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 3b88e41a41 ("KVM: SVM: Add intercept check for accessing dr registers")
Reviewed-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260612230113.684301-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

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Sean Christopherson 2026-06-12 16:01:07 -07:00

parent 8f683a4dc5

commit 55ac576a9b

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arch/x86/kvm/emulate.c

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