On Wed, May 10, 2023, at 16:27, Thomas Zimmermann wrote: > Am 10.05.23 um 16:15 schrieb Arnd Bergmann: >> On Wed, May 10, 2023, at 16:03, kernel test robot wrote: >> I think that's a preexisting bug and I have no idea what the >> correct solution is. Looking for HD64461 shows it being used >> both with inw/outw and readw/writew, so there is no way to have >> the correct type. The sh __raw_readw() definition hides this bug, >> but that is a problem with arch/sh and it probably hides others >> as well. > > The constant HD64461_IOBASE is defined as integer at > > > https://elixir.bootlin.com/linux/latest/source/arch/sh/include/asm/hd64461.h#L17 > > but fb_readw() expects a volatile-void pointer. I guess we could add a > cast somewhere to silence the problem. In the current upstream code, > that appears to be done by sh's __raw_readw() internally: > > > https://elixir.bootlin.com/linux/latest/source/arch/sh/include/asm/io.h#L35 Sure, that would make it build again, but that still doesn't make the code correct, since it's completely unclear what base address the HD64461_IOBASE is relative to. The hp6xx platform code only passes it through inw()/outw(), which take an offset relative to sh_io_port_base, but that is not initialized on hp6xx. I tried to find in the history when it broke, apparently that was in 2007 commit 34a780a0afeb ("sh: hp6xx pata_platform support."), which removed the custom inw/outw implementations. Arnd