Although there is a provision for 52 bit VA on arm64 platform, it remains unutilised and higher addresses are not allocated. In order to accommodate 4PB [2^52] virtual address space where supported, NR_CHUNKS_HIGH is changed accordingly.

Array holding addresses is changed from static allocation to dynamic allocation to accommodate its voluminous nature which otherwise might overflow the stack.

Cc: Andrew Morton akpm@linux-foundation.org Cc: David Hildenbrand david@redhat.com Cc: Shuah Khan shuah@kernel.org Cc: linux-mm@kvack.org Cc: linux-kselftest@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Chaitanya S Prakash chaitanyas.prakash@arm.com --- tools/testing/selftests/mm/virtual_address_range.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/mm/virtual_address_range.c b/tools/testing/selftests/mm/virtual_address_range.c index 50564512c5ee..bae0ceaf95b1 100644 --- a/tools/testing/selftests/mm/virtual_address_range.c +++ b/tools/testing/selftests/mm/virtual_address_range.c @@ -36,13 +36,15 @@ * till it reaches 512TB. One with size 128TB and the * other being 384TB. * - * On Arm64 the address space is 256TB and no high mappings - * are supported so far. + * On Arm64 the address space is 256TB and support for + * high mappings up to 4PB virtual address space has + * been added. */

#define NR_CHUNKS_128TB ((128 * SZ_1TB) / MAP_CHUNK_SIZE) /* Number of chunks for 128TB */ #define NR_CHUNKS_256TB (NR_CHUNKS_128TB * 2UL) #define NR_CHUNKS_384TB (NR_CHUNKS_128TB * 3UL) +#define NR_CHUNKS_3840TB (NR_CHUNKS_128TB * 30UL)

#define ADDR_MARK_128TB (1UL << 47) /* First address beyond 128TB */ #define ADDR_MARK_256TB (1UL << 48) /* First address beyond 256TB */ @@ -51,7 +53,7 @@ #define HIGH_ADDR_MARK ADDR_MARK_256TB #define HIGH_ADDR_SHIFT 49 #define NR_CHUNKS_LOW NR_CHUNKS_256TB -#define NR_CHUNKS_HIGH 0 +#define NR_CHUNKS_HIGH NR_CHUNKS_3840TB #else #define HIGH_ADDR_MARK ADDR_MARK_128TB #define HIGH_ADDR_SHIFT 48 @@ -101,7 +103,7 @@ static int validate_lower_address_hint(void) int main(int argc, char *argv[]) { char *ptr[NR_CHUNKS_LOW]; - char *hptr[NR_CHUNKS_HIGH]; + char **hptr; char *hint; unsigned long i, lchunks, hchunks;

@@ -119,6 +121,9 @@ int main(int argc, char *argv[]) return 1; } lchunks = i; + hptr = (char **) calloc(NR_CHUNKS_HIGH, sizeof(char *)); + if (hptr == NULL) + return 1;

for (i = 0; i < NR_CHUNKS_HIGH; i++) { hint = hind_addr(); @@ -139,5 +144,6 @@ int main(int argc, char *argv[]) for (i = 0; i < hchunks; i++) munmap(hptr[i], MAP_CHUNK_SIZE);

+ free(hptr); return 0; }