diff options
| author | Sean Christopherson <seanjc@google.com> | 2024-02-09 14:16:58 -0800 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-04-09 10:24:36 -0700 |
| commit | 0c4765140351e22d1568eca2c62c505e07151887 (patch) | |
| tree | 51c38d5f3bd4bd0a177bf513dfbe21126a8866ca /arch/x86/kvm/vmx/nested.c | |
| parent | fec50db7033ea478773b159e0e2efb135270e3b7 (diff) | |
KVM: nVMX: Clear EXIT_QUALIFICATION when injecting an EPT Misconfig
Explicitly clear the EXIT_QUALIFCATION field when injecting an EPT
misconfig into L1, as required by the VMX architecture. Per the SDM:
This field is saved for VM exits due to the following causes:
debug exceptions; page-fault exceptions; start-up IPIs (SIPIs);
system-management interrupts (SMIs) that arrive immediately after the
execution of I/O instructions; task switches; INVEPT; INVLPG; INVPCID;
INVVPID; LGDT; LIDT; LLDT; LTR; SGDT; SIDT; SLDT; STR; VMCLEAR; VMPTRLD;
VMPTRST; VMREAD; VMWRITE; VMXON; WBINVD; WBNOINVD; XRSTORS; XSAVES;
control-register accesses; MOV DR; I/O instructions; MWAIT; accesses to
the APIC-access page; EPT violations; EOI virtualization; APIC-write
emulation; page-modification log full; SPP-related events; and
instruction timeout. For all other VM exits, this field is cleared.
Generating EXIT_QUALIFICATION from vcpu->arch.exit_qualification is wrong
for all (two) paths that lead to nested_ept_inject_page_fault(). For EPT
violations (the common case), vcpu->arch.exit_qualification will have been
set by handle_ept_violation() to vmcs02.EXIT_QUALIFICATION, i.e. contains
the information of a EPT violation and thus is likely non-zero.
For an EPT misconfig, which can reach FNAME(walk_addr_generic) and thus
inject a nEPT misconfig if KVM created an MMIO SPTE that became stale,
vcpu->arch.exit_qualification will hold the information from the last EPT
violation VM-Exit, as vcpu->arch.exit_qualification is _only_ written by
handle_ept_violation().
Fixes: 4704d0befb07 ("KVM: nVMX: Exiting from L2 to L1")
Link: https://lore.kernel.org/r/20240209221700.393189-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86/kvm/vmx/nested.c')
| -rw-r--r-- | arch/x86/kvm/vmx/nested.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index d05ddf751491..695558ff40e1 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -417,10 +417,12 @@ static void nested_ept_inject_page_fault(struct kvm_vcpu *vcpu, vmx->nested.pml_full = false; exit_qualification &= INTR_INFO_UNBLOCK_NMI; } else { - if (fault->error_code & PFERR_RSVD_MASK) + if (fault->error_code & PFERR_RSVD_MASK) { vm_exit_reason = EXIT_REASON_EPT_MISCONFIG; - else + exit_qualification = 0; + } else { vm_exit_reason = EXIT_REASON_EPT_VIOLATION; + } /* * Although the caller (kvm_inject_emulated_page_fault) would |