riscv: Fix sparse warning in __get_user_error()

We used to assign 0 to x without an appropriate cast which results in
sparse complaining when x is a pointer:

>> block/ioctl.c:72:39: sparse: sparse: Using plain integer as NULL pointer

So fix this by casting 0 to the correct type of x.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202508062321.gHv4kvuY-lkp@intel.com/
Fixes: f6bff7827a48 ("riscv: uaccess: use 'asm_goto_output' for get_user()")
Cc: stable@vger.kernel.org
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Cyril Bur <cyrilbur@tenstorrent.com>
Link: https://lore.kernel.org/r/20250903-dev-alex-sparse_warnings_v1-v1-1-7e6350beb700@rivosinc.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>

diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
index 22e3f52a763d1c0350e8185225e4c99aac3fc549..551e7490737effb2c238e6a4db50293ece7c9df9 100644 (file)
--- a/arch/riscv/include/asm/uaccess.h
+++ b/arch/riscv/include/asm/uaccess.h
@@ -209,7 +209,7 @@ do {                                                                        \
                err = 0;                                                \
                break;                                                  \
 __gu_failed:                                                           \
-               x = 0;                                                  \
+               x = (__typeof__(x))0;                                   \
                err = -EFAULT;                                          \
 } while (0)