Commit fa7b9a805c79 ("tools/selftest/vm: allow choosing mem size and page size in map_hugetlb") added the possibility to change the size of memory mapped for the test, but left the read and write test using the default value. This is unnoticed when mapping a length greater than the default one, but segfaults otherwise.
Fix read_bytes() and write_bytes() by giving them the real length.
Also fix the call to munmap().
Fixes: fa7b9a805c79 ("tools/selftest/vm: allow choosing mem size and page size in map_hugetlb") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy christophe.leroy@c-s.fr --- tools/testing/selftests/vm/map_hugetlb.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/tools/testing/selftests/vm/map_hugetlb.c b/tools/testing/selftests/vm/map_hugetlb.c index 5a2d7b8efc40..6af951900aa3 100644 --- a/tools/testing/selftests/vm/map_hugetlb.c +++ b/tools/testing/selftests/vm/map_hugetlb.c @@ -45,20 +45,20 @@ static void check_bytes(char *addr) printf("First hex is %x\n", *((unsigned int *)addr)); }
-static void write_bytes(char *addr) +static void write_bytes(char *addr, size_t length) { unsigned long i;
- for (i = 0; i < LENGTH; i++) + for (i = 0; i < length; i++) *(addr + i) = (char)i; }
-static int read_bytes(char *addr) +static int read_bytes(char *addr, size_t length) { unsigned long i;
check_bytes(addr); - for (i = 0; i < LENGTH; i++) + for (i = 0; i < length; i++) if (*(addr + i) != (char)i) { printf("Mismatch at %lu\n", i); return 1; @@ -96,11 +96,11 @@ int main(int argc, char **argv)
printf("Returned address is %p\n", addr); check_bytes(addr); - write_bytes(addr); - ret = read_bytes(addr); + write_bytes(addr, length); + ret = read_bytes(addr, length);
/* munmap() length of MAP_HUGETLB memory must be hugepage aligned */ - if (munmap(addr, LENGTH)) { + if (munmap(addr, length)) { perror("munmap"); exit(1); }