On Thu, Aug 06, 2020 at 04:17:13AM +0800, kernel test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git vhost > head: 4c05433bc6fb4ae172270f0279be8ba89a3da64f > commit: b025584098e621d88894d28e80af686958e273af [32/52] virtio_input: convert to LE accessors > config: parisc-randconfig-r003-20200805 (attached as .config) > compiler: hppa-linux-gcc (GCC) 9.3.0 > reproduce (this is a W=1 build): > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > git checkout b025584098e621d88894d28e80af686958e273af > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=parisc Weird. So the following fixes it: diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index ecb166c824bb..8fe857e27ef3 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -357,10 +357,10 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val) */ #define virtio_le_to_cpu(x) \ _Generic((x), \ - __u8: (x), \ - __le16: le16_to_cpu(x), \ - __le32: le32_to_cpu(x), \ - __le64: le64_to_cpu(x) \ + __u8: (u8)(x), \ + __le16: (u16)le16_to_cpu(x), \ + __le32: (u32)le32_to_cpu(x), \ + __le64: (u64)le64_to_cpu(x) \ ) #define virtio_cpu_to_le(x, m) \ @@ -400,7 +400,6 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val) *(ptr) = virtio_le_to_cpu(virtio_cread_v); \ } while(0) -/* Config space accessors. */ #define virtio_cwrite_le(vdev, structname, member, ptr) \ do { \ typeof(((structname*)0)->member) virtio_cwrite_v = \ How could this be? le16_to_cpu doesn't return a u16? I suspect this compiler gets confused by _Generic. Let's hope it does not also miscompile the code :) > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot > > All warnings (new ones prefixed by >>): > > In file included from include/linux/irqflags.h:15, > from include/asm-generic/cmpxchg-local.h:6, > from arch/parisc/include/asm/cmpxchg.h:89, > from arch/parisc/include/asm/atomic.h:10, > from include/linux/atomic.h:7, > from arch/parisc/include/asm/bitops.h:13, > from include/linux/bitops.h:29, > from include/linux/kernel.h:12, > from include/linux/list.h:9, > from include/linux/module.h:12, > from drivers/virtio/virtio_input.c:2: > drivers/virtio/virtio_input.c: In function 'virtinput_probe': > >> include/linux/typecheck.h:12:18: warning: comparison of distinct pointer types lacks a cast > 12 | (void)(&__dummy == &__dummy2); \ > | ^~ > include/linux/virtio_config.h:405:3: note: in expansion of macro 'typecheck' > 405 | typecheck(typeof(virtio_le_to_cpu(virtio_cread_v)), *(ptr)); \ > | ^~~~~~~~~ > drivers/virtio/virtio_input.c:247:3: note: in expansion of macro 'virtio_cread_le' > 247 | virtio_cread_le(vi->vdev, struct virtio_input_config, > | ^~~~~~~~~~~~~~~ > >> include/linux/typecheck.h:12:18: warning: comparison of distinct pointer types lacks a cast > 12 | (void)(&__dummy == &__dummy2); \ > | ^~ > include/linux/virtio_config.h:405:3: note: in expansion of macro 'typecheck' > 405 | typecheck(typeof(virtio_le_to_cpu(virtio_cread_v)), *(ptr)); \ > | ^~~~~~~~~ > drivers/virtio/virtio_input.c:249:3: note: in expansion of macro 'virtio_cread_le' > 249 | virtio_cread_le(vi->vdev, struct virtio_input_config, > | ^~~~~~~~~~~~~~~ > >> include/linux/typecheck.h:12:18: warning: comparison of distinct pointer types lacks a cast > 12 | (void)(&__dummy == &__dummy2); \ > | ^~ > include/linux/virtio_config.h:405:3: note: in expansion of macro 'typecheck' > 405 | typecheck(typeof(virtio_le_to_cpu(virtio_cread_v)), *(ptr)); \ > | ^~~~~~~~~ > drivers/virtio/virtio_input.c:251:3: note: in expansion of macro 'virtio_cread_le' > 251 | virtio_cread_le(vi->vdev, struct virtio_input_config, > | ^~~~~~~~~~~~~~~ > >> include/linux/typecheck.h:12:18: warning: comparison of distinct pointer types lacks a cast > 12 | (void)(&__dummy == &__dummy2); \ > | ^~ > include/linux/virtio_config.h:405:3: note: in expansion of macro 'typecheck' > 405 | typecheck(typeof(virtio_le_to_cpu(virtio_cread_v)), *(ptr)); \ > | ^~~~~~~~~ > drivers/virtio/virtio_input.c:253:3: note: in expansion of macro 'virtio_cread_le' > 253 | virtio_cread_le(vi->vdev, struct virtio_input_config, > | ^~~~~~~~~~~~~~~ > > vim +12 include/linux/typecheck.h > > e0deaff470900a4 Andrew Morton 2008-07-25 4 > e0deaff470900a4 Andrew Morton 2008-07-25 5 /* > e0deaff470900a4 Andrew Morton 2008-07-25 6 * Check at compile time that something is of a particular type. > e0deaff470900a4 Andrew Morton 2008-07-25 7 * Always evaluates to 1 so you may use it easily in comparisons. > e0deaff470900a4 Andrew Morton 2008-07-25 8 */ > e0deaff470900a4 Andrew Morton 2008-07-25 9 #define typecheck(type,x) \ > e0deaff470900a4 Andrew Morton 2008-07-25 10 ({ type __dummy; \ > e0deaff470900a4 Andrew Morton 2008-07-25 11 typeof(x) __dummy2; \ > e0deaff470900a4 Andrew Morton 2008-07-25 @12 (void)(&__dummy == &__dummy2); \ > e0deaff470900a4 Andrew Morton 2008-07-25 13 1; \ > e0deaff470900a4 Andrew Morton 2008-07-25 14 }) > e0deaff470900a4 Andrew Morton 2008-07-25 15 > > :::::: The code at line 12 was first introduced by commit > :::::: e0deaff470900a4c3222ca7139f6c9639e26a2f5 split the typecheck macros out of include/linux/kernel.h > > :::::: TO: Andrew Morton > :::::: CC: Linus Torvalds > > --- > 0-DAY CI Kernel Test Service, Intel Corporation > https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org