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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-01-03 15:44:38 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-01-03 15:44:38 +0300
commit824adf37ee9ddf3ecba1bc245507bc5953dda268 (patch)
treeee85366f9e2c019b58492558d8ad406df35fd260 /arch/x86/kvm/vmx/vmx.c
parentf2ee4759fb700b32a1bd830960fe86bf6bdfd0ab (diff)
parentc9e6606c7fe92b50a02ce51dda82586ebdf99b48 (diff)
downloadlinux-824adf37ee9ddf3ecba1bc245507bc5953dda268.tar.xz
Merge 5.16-rc8 into char-misc-next
We need the fixes in here as well for testing. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
-rw-r--r--arch/x86/kvm/vmx/vmx.c45
1 files changed, 32 insertions, 13 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 5aadad3e7367..0dbf94eb954f 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1363,6 +1363,11 @@ void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
vmx->emulation_required = vmx_emulation_required(vcpu);
}
+static bool vmx_get_if_flag(struct kvm_vcpu *vcpu)
+{
+ return vmx_get_rflags(vcpu) & X86_EFLAGS_IF;
+}
+
u32 vmx_get_interrupt_shadow(struct kvm_vcpu *vcpu)
{
u32 interruptibility = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO);
@@ -3959,8 +3964,7 @@ static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
if (pi_test_and_set_on(&vmx->pi_desc))
return 0;
- if (vcpu != kvm_get_running_vcpu() &&
- !kvm_vcpu_trigger_posted_interrupt(vcpu, false))
+ if (!kvm_vcpu_trigger_posted_interrupt(vcpu, false))
kvm_vcpu_kick(vcpu);
return 0;
@@ -5877,18 +5881,14 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
vmx_flush_pml_buffer(vcpu);
/*
- * We should never reach this point with a pending nested VM-Enter, and
- * more specifically emulation of L2 due to invalid guest state (see
- * below) should never happen as that means we incorrectly allowed a
- * nested VM-Enter with an invalid vmcs12.
+ * KVM should never reach this point with a pending nested VM-Enter.
+ * More specifically, short-circuiting VM-Entry to emulate L2 due to
+ * invalid guest state should never happen as that means KVM knowingly
+ * allowed a nested VM-Enter with an invalid vmcs12. More below.
*/
if (KVM_BUG_ON(vmx->nested.nested_run_pending, vcpu->kvm))
return -EIO;
- /* If guest state is invalid, start emulating */
- if (vmx->emulation_required)
- return handle_invalid_guest_state(vcpu);
-
if (is_guest_mode(vcpu)) {
/*
* PML is never enabled when running L2, bail immediately if a
@@ -5910,10 +5910,30 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
*/
nested_mark_vmcs12_pages_dirty(vcpu);
+ /*
+ * Synthesize a triple fault if L2 state is invalid. In normal
+ * operation, nested VM-Enter rejects any attempt to enter L2
+ * with invalid state. However, those checks are skipped if
+ * state is being stuffed via RSM or KVM_SET_NESTED_STATE. If
+ * L2 state is invalid, it means either L1 modified SMRAM state
+ * or userspace provided bad state. Synthesize TRIPLE_FAULT as
+ * doing so is architecturally allowed in the RSM case, and is
+ * the least awful solution for the userspace case without
+ * risking false positives.
+ */
+ if (vmx->emulation_required) {
+ nested_vmx_vmexit(vcpu, EXIT_REASON_TRIPLE_FAULT, 0, 0);
+ return 1;
+ }
+
if (nested_vmx_reflect_vmexit(vcpu))
return 1;
}
+ /* If guest state is invalid, start emulating. L2 is handled above. */
+ if (vmx->emulation_required)
+ return handle_invalid_guest_state(vcpu);
+
if (exit_reason.failed_vmentry) {
dump_vmcs(vcpu);
vcpu->run->exit_reason = KVM_EXIT_FAIL_ENTRY;
@@ -6608,9 +6628,7 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
* consistency check VM-Exit due to invalid guest state and bail.
*/
if (unlikely(vmx->emulation_required)) {
-
- /* We don't emulate invalid state of a nested guest */
- vmx->fail = is_guest_mode(vcpu);
+ vmx->fail = 0;
vmx->exit_reason.full = EXIT_REASON_INVALID_STATE;
vmx->exit_reason.failed_vmentry = 1;
@@ -7579,6 +7597,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
.cache_reg = vmx_cache_reg,
.get_rflags = vmx_get_rflags,
.set_rflags = vmx_set_rflags,
+ .get_if_flag = vmx_get_if_flag,
.tlb_flush_all = vmx_flush_tlb_all,
.tlb_flush_current = vmx_flush_tlb_current,