On Fri, May 5, 2017 at 7:13 PM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Fri, May 05, 2017 at 01:57:23PM +0200, Arnd Bergmann wrote:
>> We get a warning about a broken pointer conversion on 64-bit architectures:
>>
>> drivers/message/i2o/i2o_config.c: In function 'i2o_cfg_passthru':
>> drivers/message/i2o/i2o_config.c:893:19: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> (p->virt, (void __user *)sg[i].addr_bus,
>> ^
>> drivers/message/i2o/i2o_config.c:953:10: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> ((void __user *)sg[j].addr_bus, sg_list[j].virt,
>> ^
>>
>> This has clearly never worked right, so we can add an #ifdef around the code.
>> The driver was moved to staging in linux-4.0 and finally removed in 4.2,
>> so upstream does not have a fix for it.
>>
>> The driver originally got this mostly right, though probably by accident.
>
> I fixed this in a different way, doing the cast to make things be quiet,
> as was done in other places in the driver. You were copied on that
> patch when it was added to my tree, right?
I missed it when you sent it, but looking at it now, I think it introduces
another warning, on 32-bit architectures:
- (p->virt, (void __user *)sg[i].addr_bus,
+ (p->virt, (void __user
*)(u64)sg[i].addr_bus,
I think you need '(void __user *)(uintptr_t)sg[i].addr_bus' to
shut up the warning for all builds.
Arnd