* Re: [RTF] kvm:x86:Fix error checking in the function pf_interception
[not found] <1438913423-30959-1-git-send-email-xerofoify@gmail.com>
@ 2015-08-07 7:31 ` Joerg Roedel
0 siblings, 0 replies; only message in thread
From: Joerg Roedel @ 2015-08-07 7:31 UTC (permalink / raw)
To: Nicholas Krause; +Cc: gleb, pbonzini, x86, kvm, linux-kernel
On Thu, Aug 06, 2015 at 10:10:23PM -0400, Nicholas Krause wrote:
> This fixes error checking in the function pf_interception by
> checking if the call to kvm_mmu_unprotect_page_virt returns
> zero to indicate the function has failed internally and if
> this occurs we must return immediately to the caller of the
> function pf_interception with the return value of zero from
> the call to the function kvm_mmu_unprotect_page_virt to indicate
> failure to the caller of the function pf_interception.
>
> Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
> ---
> arch/x86/kvm/svm.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 8e0c084..a57aee1 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -1814,8 +1814,11 @@ static int pf_interception(struct vcpu_svm *svm)
> error_code = svm->vmcb->control.exit_info_1;
>
> trace_kvm_page_fault(fault_address, error_code);
> - if (!npt_enabled && kvm_event_needs_reinjection(&svm->vcpu))
> - kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address);
> + if (!npt_enabled && kvm_event_needs_reinjection(&svm->vcpu)) {
> + r = kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address);
> + if (!r)
> + break;
> + }
NAK. kvm_mmu_unprotect_page_virt does not return an error but whether it
unprotected a page or not. This patch breaks SVM.
^ permalink raw reply [flat|nested] only message in thread