| Message ID | 20240119131429.172448-1-npache@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] selftests: mm: fix map_hugetlb failure on 64K page size systems | expand |
On Fri, 19 Jan 2024 06:14:29 -0700 Nico Pache <npache@redhat.com> wrote: > On systems with 64k page size and 512M huge page sizes, the allocation > and test succeeds but errors out at the munmap. As the comment states, > munmap will failure if its not HUGEPAGE aligned. This is due to the > length of the mapping being 1/2 the size of the hugepage causing the > munmap to not be hugepage aligned. Fix this by making the mapping length > the full hugepage if the hugepage is larger than the length of the > mapping. Is Fixes: fa7b9a805c79 ("tools/selftest/vm: allow choosing mem size and page size in map_hugetlb") a suitable Fixes: target for this? > --- a/tools/testing/selftests/mm/map_hugetlb.c > +++ b/tools/testing/selftests/mm/map_hugetlb.c > @@ -15,6 +15,7 @@ > #include <unistd.h> > #include <sys/mman.h> > #include <fcntl.h> > +#include "vm_util.h" > > #define LENGTH (256UL*1024*1024) > #define PROTECTION (PROT_READ | PROT_WRITE) > @@ -58,10 +59,16 @@ int main(int argc, char **argv) > { > void *addr; > int ret; > + size_t hugepage_size; > size_t length = LENGTH; > int flags = FLAGS; > int shift = 0; > > + hugepage_size = default_huge_page_size(); > + /* munmap with fail if the length is not page aligned */ > + if (hugepage_size > length) > + length = hugepage_size; > + > if (argc > 1) > length = atol(argv[1]) << 20; > if (argc > 2) { > -- > 2.43.0
Hi Andrew, No, I think it's always been broken-- I don't think the test was written with 512M huge page sizes in mind. -- Nico On Sat, Jan 20, 2024 at 9:39 PM Andrew Morton <akpm@linux-foundation.org> wrote: > > On Fri, 19 Jan 2024 06:14:29 -0700 Nico Pache <npache@redhat.com> wrote: > > > On systems with 64k page size and 512M huge page sizes, the allocation > > and test succeeds but errors out at the munmap. As the comment states, > > munmap will failure if its not HUGEPAGE aligned. This is due to the > > length of the mapping being 1/2 the size of the hugepage causing the > > munmap to not be hugepage aligned. Fix this by making the mapping length > > the full hugepage if the hugepage is larger than the length of the > > mapping. > > Is > > Fixes: fa7b9a805c79 ("tools/selftest/vm: allow choosing mem size and page size in map_hugetlb") > > a suitable Fixes: target for this? > > > --- a/tools/testing/selftests/mm/map_hugetlb.c > > +++ b/tools/testing/selftests/mm/map_hugetlb.c > > @@ -15,6 +15,7 @@ > > #include <unistd.h> > > #include <sys/mman.h> > > #include <fcntl.h> > > +#include "vm_util.h" > > > > #define LENGTH (256UL*1024*1024) > > #define PROTECTION (PROT_READ | PROT_WRITE) > > @@ -58,10 +59,16 @@ int main(int argc, char **argv) > > { > > void *addr; > > int ret; > > + size_t hugepage_size; > > size_t length = LENGTH; > > int flags = FLAGS; > > int shift = 0; > > > > + hugepage_size = default_huge_page_size(); > > + /* munmap with fail if the length is not page aligned */ > > + if (hugepage_size > length) > > + length = hugepage_size; > > + > > if (argc > 1) > > length = atol(argv[1]) << 20; > > if (argc > 2) { > > -- > > 2.43.0 >
diff --git a/tools/testing/selftests/mm/map_hugetlb.c b/tools/testing/selftests/mm/map_hugetlb.c index 193281560b61..86e8f2048a40 100644 --- a/tools/testing/selftests/mm/map_hugetlb.c +++ b/tools/testing/selftests/mm/map_hugetlb.c @@ -15,6 +15,7 @@ #include <unistd.h> #include <sys/mman.h> #include <fcntl.h> +#include "vm_util.h" #define LENGTH (256UL*1024*1024) #define PROTECTION (PROT_READ | PROT_WRITE) @@ -58,10 +59,16 @@ int main(int argc, char **argv) { void *addr; int ret; + size_t hugepage_size; size_t length = LENGTH; int flags = FLAGS; int shift = 0; + hugepage_size = default_huge_page_size(); + /* munmap with fail if the length is not page aligned */ + if (hugepage_size > length) + length = hugepage_size; + if (argc > 1) length = atol(argv[1]) << 20; if (argc > 2) {
On systems with 64k page size and 512M huge page sizes, the allocation and test succeeds but errors out at the munmap. As the comment states, munmap will failure if its not HUGEPAGE aligned. This is due to the length of the mapping being 1/2 the size of the hugepage causing the munmap to not be hugepage aligned. Fix this by making the mapping length the full hugepage if the hugepage is larger than the length of the mapping. Signed-off-by: Nico Pache <npache@redhat.com> --- tools/testing/selftests/mm/map_hugetlb.c | 7 +++++++ 1 file changed, 7 insertions(+)