KVM: x86: Do not change ICR on write to APIC_SELF_IPI

[ Upstream commit d22a81b304 ]

Emulating writes to SELF_IPI with a write to ICR has an unwanted side effect:
the value of ICR in vAPIC page gets changed.  The lists SELF_IPI as write-only,
with no associated MMIO offset, so any write should have no visible side
effect in the vAPIC page.

Reported-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Paolo Bonzini 2022-02-24 09:53:36 -05:00 committed by Greg Kroah-Hartman
parent aac4b0e982
commit 0fa88cd8ee
1 changed files with 3 additions and 4 deletions

View File

@ -2125,10 +2125,9 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
break;
case APIC_SELF_IPI:
if (apic_x2apic_mode(apic)) {
kvm_lapic_reg_write(apic, APIC_ICR,
APIC_DEST_SELF | (val & APIC_VECTOR_MASK));
} else
if (apic_x2apic_mode(apic))
kvm_apic_send_ipi(apic, APIC_DEST_SELF | (val & APIC_VECTOR_MASK), 0);
else
ret = 1;
break;
default: