On Wed, May 10, 2017 at 1:14 AM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > On Wed, May 10, 2017 at 09:08:41AM +0100, Al Viro wrote: >> On Wed, May 10, 2017 at 09:37:04AM +0200, Arnd Bergmann wrote: >> >> > > How about trying to remove all of them? If we could actually get rid >> > > of all of them, we could drop the arch support, and we'd get faster, >> > > simpler, shorter uaccess code throughout the kernel. >> >> BTW, not all get_user() under KERNEL_DS are plain loads. There is an >> exception - probe_kernel_read(). > > And various calls that looks like opencoded versions, e.g. drivers/dio > or the ELF loader. > > But in the long run we'll just need a separate primitive for that, > but that can wait until the set_fs calls outside the core code are > gone. I suspect that, on most arches, the primitive is called __copy_from_user(). We could make the generic code do that except where overridden. -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
