On Tue, Oct 16, 2018 at 5:05 AM Guo Ren <ren_guo@xxxxxxxxx> wrote: > > The patch adds "user access from kernel" codes. > > Signed-off-by: Guo Ren <ren_guo@xxxxxxxxx> > Cc: Arnd Bergmann <arnd@xxxxxxxx> > --- > arch/csky/include/asm/uaccess.h | 416 ++++++++++++++++++++++++++++++++++++++++ > arch/csky/lib/usercopy.c | 262 +++++++++++++++++++++++++ > 2 files changed, 678 insertions(+) > create mode 100644 arch/csky/include/asm/uaccess.h > create mode 100644 arch/csky/lib/usercopy.c Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx> The 64-bit __put_user() is usually what everyone gets wrong, but your version seems fine. Also the access_ok() checks and the copy_to_user() result value all look correct. Arnd