On Mon, 16 Feb 2015 13:16:41 +0100 Thomas Huth <[email protected]> wrote:
> On s390, we've got to make sure to hold the IPTE lock while accessing > logical memory. So let's add an ioctl for reading and writing logical > memory to provide this feature for userspace, too. > > Signed-off-by: Thomas Huth <[email protected]> > --- > Documentation/virtual/kvm/api.txt | 45 +++++++++++++++++++++++ > arch/s390/kvm/gaccess.c | 22 +++++++++++ > arch/s390/kvm/gaccess.h | 2 + > arch/s390/kvm/kvm-s390.c | 70 > +++++++++++++++++++++++++++++++++++++ > include/uapi/linux/kvm.h | 20 ++++++++++ > 5 files changed, 159 insertions(+), 0 deletions(-) Looks good, except for one minor thing: > +static long kvm_s390_guest_mem_op(struct kvm_vcpu *vcpu, > + struct kvm_s390_mem_op *mop) > +{ > + void __user *uaddr = (void __user *)mop->buf; > + void *tmpbuf = NULL; > + int r, srcu_idx; > + const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION > + | KVM_S390_MEMOP_F_CHECK_ONLY; > + > + if (mop->flags & ~supported_flags) > + return -EINVAL; > + > + if (mop->size > 16 * PAGE_SIZE) > + return -E2BIG; Do you want to document this limit? Or make it discoverable by having the capability check return the number of pages? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
