On 07/13/2014 10:25 PM, Lars-Peter Clausen wrote: > On 07/13/2014 04:03 PM, Richard Weinberger wrote: >> Am 13.07.2014 15:56, schrieb Lars-Peter Clausen: >>> On 07/13/2014 03:40 PM, Richard Weinberger wrote: >>>> Am 13.07.2014 15:26, schrieb Lars-Peter Clausen: >>>>> On 07/13/2014 11:45 AM, Richard Weinberger wrote: >>>>>> Am 13.07.2014 11:27, schrieb Lennox Wu: >>>>>>> As I said before, some configurations don't make sense. >>>>>> >>>>>> If such a configuration can be achieved using allmod/yesconfig it has to be fixed. >>>>>> Chen's fixes seem reasonable as not all architectures support iomem. >>>>> >>>>> Maybe we should stub out ioremap() and friends when COMPILE_TEST is enabled to avoid these linker errors. That's in my opinion better than turning most of the 'depends on >>>>> COMPILE_TEST' into 'depends on COMPILE_TEST && HAS_IOMEM'. The issue comes up quite a lot and it is often overlooked when adding a driver that can be build when COMPILE_TEST is >>>>> enabled. >>>> >>>> And what should this stub do? >>>> Except calling BUG()... >>> >>> return NULL; >>> >>> It's for compile testing, it's not meant to work at runtime. >> >> Hm, I really don't like the idea of having a non-working kernel. >> IMHO either it should build _and_ run and nothing else. >> Greg, what do you think? > > The kernel will still be working fine and you can run it on a system. The drivers which use ioremap() or similar are probably not instantiated on a system that does not provide HAS_IOMEM. But even if it was the driver should handle ioremap() returning NULL gracefully and abort the driver probe. That said you'll probably not run a kernel that was built with COMPILE_TEST on your real hardware since it contains so many drivers that are completely useless on your hardware. The idea of COMPILE_TEST is to have as much compile test exposure as possible to the code that is enabled by COMPILE_TEST. Stubbing out ioremap() and friends when HAS_IOMEM is not set and COMPILE_TEST is set makes it easier to get there. > For me, welcome Greg's idea or suggestion for it. And also if the reply contents are wrapped (e.g. within 80 or less), that will generate a better display under other members' email clients. Thanks -- Chen Gang Open share and attitude like air water and life which God blessed -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html