Re: [PATCH] KVM: nVMX: Fix consistency check on injected exception error code

From: Jim Mattson
Date: Tue Oct 01 2019 - 12:28:51 EST


On Tue, Oct 1, 2019 at 9:21 AM Sean Christopherson
<sean.j.christopherson@xxxxxxxxx> wrote:
>
> Current versions of Intel's SDM incorrectly state that "bits 31:15 of
> the VM-Entry exception error-code field" must be zero. In reality, bits
> 31:16 must be zero, i.e. error codes are 16-bit values.
>
> The bogus error code check manifests as an unexpected VM-Entry failure
> due to an invalid code field (error number 7) in L1, e.g. when injecting
> a #GP with error_code=0x9f00.
>
> Nadav previously reported the bug[*], both to KVM and Intel, and fixed
> the associated kvm-unit-test.
>
> [*] https://patchwork.kernel.org/patch/11124749/
>
> Reported-by: Nadav Amit <namit@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>