On 03/02/2015 16:16, Thomas Huth wrote: > Actually, I'd prefer to keep the "virtual" in the defines for the type > of operation below: When it comes to s390 storage keys, we likely might > need some calls for reading and writing to physical memory, too. Then > we could simply extend this ioctl instead of inventing a new one.
Can you explain why it is necessary to read/write physical addresses from user space? In the case of QEMU, I'm worried that you would have to invent your own memory read/write APIs that are different from everything else. On real s390 zPCI, does bus-master DMA update storage keys? >> Not really true, as you don't check it. So "It is not used by KVM with >> the currently defined set of flags" is a better explanation. > > ok ... and maybe add "should be set to zero" ? If you don't check it, it is misleading to document this. Paolo
