Re: [PATCH] riscv: fix __user annotation in traps_misaligned.c

From: Christoph Hellwig
Date: Fri Nov 24 2023 - 01:18:20 EST


On Thu, Nov 23, 2023 at 02:16:17PM +0000, Ben Dooks wrote:
> @@ -319,7 +319,7 @@ static inline int get_insn(struct pt_regs *regs, ulong mepc, ulong *r_insn)
> static inline int load_u8(struct pt_regs *regs, const u8 *addr, u8 *r_val)
> {
> if (user_mode(regs)) {
> - return __get_user(*r_val, addr);
> + return __get_user(*r_val, (u8 __user *)addr);
> } else {
> *r_val = *addr;
> return 0;

This is the wrong way to approach it. Pass the untype unsigned long
from the caller instead and do a single round of casts from that
depending on the address_space.

And please also remove this horrible else after return entipattern
while you're at it.