On 05/12/2017 01:53, Wanpeng Li wrote: >> That seems like a convoluted path to produce an illegal RFLAGS value. >> What's to prevent syzkaller from simply clearing bit 1 of RFLAGS with >> the KVM_SET_REGS ioctl? > Yeah, it can happen. Which do you prefer, ioctl fails or | > X86_EFLAGS_FIXED unconditionally in the ioctl handler in kvm? I suspect somebody might be passing an all-zero regs struct to KVM_SET_REGS, so ORing X86_EFLAGS_FIXED is better. Thanks, Paolo
