On Mon, 2019-08-19 at 12:05 +0200, Geert Uytterhoeven wrote: > When compiling on 32-bit: > > drivers/infiniband/sw/siw/siw_cq.c:76:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] > drivers/infiniband/sw/siw/siw_qp.c:952:28: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] [] > Fix this by applying the following rules: > 1. When printing a u64, the %llx format specififer should be used, > instead of casting to a pointer, and printing the latter. > 2. When assigning a pointer to a u64, the pointer should be cast to > uintptr_t, not u64, > 3. When casting from u64 to pointer, an intermediate cast to uintptr_t > should be added, I think a cast to unsigned long is rather more common. uintptr_t is used ~1300 times in the kernel. I believe a cast to unsigned long is much more common. It might be useful to add something to the Documentation for this style. Documentation/process/coding-style.rst And trivia: > > diff --git a/drivers/infiniband/sw/siw/siw_verbs.c b/drivers/infiniband/sw/siw/siw_verbs.c [] > @@ -842,8 +842,8 @@ int siw_post_send(struct ib_qp *base_qp, const struct ib_send_wr *wr, > rv = -EINVAL; > break; > } > - siw_dbg_qp(qp, "opcode %d, flags 0x%x, wr_id 0x%p\n", > - sqe->opcode, sqe->flags, (void *)sqe->id); > + siw_dbg_qp(qp, "opcode %d, flags 0x%x, wr_id 0x%llx\n", > + sqe->opcode, sqe->flags, sqe->id); Printing possible pointers as %llx is generally not a good idea given the desire for %p obfuscation.
