From: Nico Pache npache@redhat.com
[ Upstream commit 91b80cc5b39f00399e8e2d17527cad2c7fa535e2 ]
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.
Link: https://lkml.kernel.org/r/20240119131429.172448-1-npache@redhat.com Signed-off-by: Nico Pache npache@redhat.com Cc: Donet Tom donettom@linux.vnet.ibm.com Cc: Shuah Khan shuah@kernel.org Cc: Christophe Leroy christophe.leroy@c-s.fr Cc: Michael Ellerman mpe@ellerman.id.au Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/selftests/vm/map_hugetlb.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/tools/testing/selftests/vm/map_hugetlb.c b/tools/testing/selftests/vm/map_hugetlb.c index 312889edb84ab..c65c55b7a789f 100644 --- a/tools/testing/selftests/vm/map_hugetlb.c +++ b/tools/testing/selftests/vm/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) @@ -70,10 +71,16 @@ 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) {