Re: [v2, 06/21] powerpc: Avoid comparison of unsigned long >= 0 in __access_ok
From: Michael Ellerman <hidden>
Date: 2018-03-14 09:28:49
Also in:
lkml
On Fri, 2018-03-02 at 19:50:51 UTC, Mathieu Malaterre wrote:
Rewrite function-like macro into regular static inline function to avoid a
warning during macro expansion.
Fix warning (treated as error in W=1):
CC arch/powerpc/kernel/signal_32.o
In file included from ./include/linux/uaccess.h:14:0,
from ./include/asm-generic/termios-base.h:8,
from ./arch/powerpc/include/asm/termios.h:20,
from ./include/uapi/linux/termios.h:6,
from ./include/linux/tty.h:7,
from arch/powerpc/kernel/signal_32.c:36:
./include/asm-generic/termios-base.h: In function ���user_termio_to_kernel_termios���:
./arch/powerpc/include/asm/uaccess.h:52:35: error: comparison of unsigned expression >= 0 is always true [-Werror=type-limits]
(((size) == 0) || (((size) - 1) <= ((segment).seg - (addr)))))
^
./arch/powerpc/include/asm/uaccess.h:58:3: note: in expansion of macro ���__access_ok���
__access_ok((__force unsigned long)(addr), (size), get_fs()))
^~~~~~~~~~~
./arch/powerpc/include/asm/uaccess.h:262:6: note: in expansion of macro ���access_ok���
if (access_ok(VERIFY_READ, __gu_addr, (size))) \
^~~~~~~~~
./arch/powerpc/include/asm/uaccess.h:80:2: note: in expansion of macro ���__get_user_check���
__get_user_check((x), (ptr), sizeof(*(ptr)))
^~~~~~~~~~~~~~~~
./include/asm-generic/termios-base.h:36:6: note: in expansion of macro ���get_user���
if (get_user(termios->c_line, &termio->c_line) < 0)
^~~~~~~~
[...]
cc1: all warnings being treated as errors
Suggested-by: Segher Boessenkool <redacted>
Signed-off-by: Mathieu Malaterre <redacted>
Reviewed-by: Christophe Leroy <redacted>Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/ef85dffd4251ff6c23056651f6f83b cheers