On 15.10.21 17:45, Shuah Khan wrote: > On 9/18/21 1:41 AM, David Hildenbrand wrote: >> On 18.09.21 00:45, Shuah Khan wrote: >>> Hi David, >>> >>> I am running into the following warning when try to build this test: >>> >>> madv_populate.c:334:2: warning: #warning "missing MADV_POPULATE_READ or MADV_POPULATE_WRITE definition" [-Wcpp] >>> 334 | #warning "missing MADV_POPULATE_READ or MADV_POPULATE_WRITE definition" >>> | ^~~~~~~ >>> >>> >>> I see that the following handling is in place. However there is no >>> other information to explain why the check is necessary. >>> >>> #if defined(MADV_POPULATE_READ) && defined(MADV_POPULATE_WRITE) >>> >>> #else /* defined(MADV_POPULATE_READ) && defined(MADV_POPULATE_WRITE) */ >>> >>> #warning "missing MADV_POPULATE_READ or MADV_POPULATE_WRITE definition" >>> >>> I do see these defined in: >>> >>> include/uapi/asm-generic/mman-common.h:#define MADV_POPULATE_READ 22 >>> include/uapi/asm-generic/mman-common.h:#define MADV_POPULATE_WRITE 23 >>> >>> Is this the case of missing include from madv_populate.c? >> >> Hi Shuan, >> >> note that we're including "#include <sys/mman.h>", which in my >> understanding maps to the version installed on your system instead >> of the one in our build environment.ing. >> >> So as soon as you have a proper kernel + the proper headers installed >> and try to build, it would pick up MADV_POPULATE_READ and >> MADV_POPULATE_WRITE from the updated headers. That makes sense: you >> annot run any MADV_POPULATE_READ/MADV_POPULATE_WRITE tests on a kernel >> that doesn't support it. >> >> See vm/userfaultfd.c where we do something similar. >> > > Kselftest is for testing the kernel with kernel headers. That is the > reason why there is the dependency on header install. > >> >> As soon as we have a proper environment, it seems to work just fine: >> >> Linux vm-0 5.15.0-0.rc1.20210915git3ca706c189db.13.fc36.x86_64 #1 SMP Thu Sep 16 11:32:54 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux >> [root@vm-0 linux]# cat /etc/redhat-release >> Fedora release 36 (Rawhide) > > This is a distro release. We don't want to have dependency on headers > from the distro to run selftests. Hope this makes sense. > > I still see this on my test system running Linux 5.15-rc5. Did you also install Linux headers? I assume no, correct? -- Thanks, David / dhildenb
