On Thu, Aug 14, 2025, Sasha Levin wrote:
From: Sean Christopherson seanjc@google.com
[ Upstream commit 80c64c7afea1da6a93ebe88d3d29d8a60377ef80 ]
Instruct vendor code to load the guest's DR6 into hardware via a new KVM_RUN flag, and remove kvm_x86_ops.set_dr6(), whose sole purpose was to load vcpu->arch.dr6 into hardware when DR6 can be read/written directly by the guest.
Note, TDX already WARNs on any run_flag being set, i.e. will yell if KVM thinks DR6 needs to be reloaded. TDX vCPUs force KVM_DEBUGREG_AUTO_SWITCH and never clear the flag, i.e. should never observe KVM_RUN_LOAD_GUEST_DR6.
Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250610232010.162191-4-seanjc@google.com Signed-off-by: Sean Christopherson seanjc@google.com Stable-dep-of: 6b1dd26544d0 ("KVM: VMX: Preserve host's DEBUGCTLMSR_FREEZE_IN_SMM while running the guest") Signed-off-by: Sasha Levin sashal@kernel.org
Acked-by: Sean Christopherson seanjc@google.com