On Wed, Feb 26, 2020 at 7:20 PM linmiaohe <linmiaohe@xxxxxxxxxx> wrote: > > From: Miaohe Lin <linmiaohe@xxxxxxxxxx> > > When kvm_vcpu_ioctl_get_cpuid2() fails, we set cpuid->nent to the value of > vcpu->arch.cpuid_nent. But this is in vain as cpuid->nent is not copied to > userspace by copy_to_user() from call site. Also cpuid->nent is not updated > to indicate how many entries were retrieved on success case. So this ioctl > is straight up broken. And in fact, it's not used anywhere. So it should be > deprecated. I don't know how you can make the assertion that this ioctl is not used anywhere. For instance, I see a use of it in Google's code base.
