Patch "tools/selftest/vm: allow choosing mem size and page size in map_hugetlb" has been added to the 4.19-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    tools/selftest/vm: allow choosing mem size and page size in map_hugetlb

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     tools-selftest-vm-allow-choosing-mem-size-and-page-s.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit e7115befe1ee9aba30e9c3e9dc8334aac7e83d02
Author: Christophe Leroy <christophe.leroy@xxxxxx>
Date:   Fri Feb 8 15:02:55 2019 +0000

    tools/selftest/vm: allow choosing mem size and page size in map_hugetlb
    
    [ Upstream commit fa7b9a805c797b729022029aaa3a2b7c35fff4c6 ]
    
    map_hugetlb maps 256Mbytes of memory with default hugepage size.
    
    This patch allows the user to pass the size and page shift as an
    argument in order to use different size and page size.
    
    Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
    Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
    Stable-dep-of: 91b80cc5b39f ("selftests: mm: fix map_hugetlb failure on 64K page size systems")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/tools/testing/selftests/vm/map_hugetlb.c b/tools/testing/selftests/vm/map_hugetlb.c
index 9b777fa95f090..5a2d7b8efc407 100644
--- a/tools/testing/selftests/vm/map_hugetlb.c
+++ b/tools/testing/selftests/vm/map_hugetlb.c
@@ -23,6 +23,14 @@
 #define MAP_HUGETLB 0x40000 /* arch specific */
 #endif
 
+#ifndef MAP_HUGE_SHIFT
+#define MAP_HUGE_SHIFT 26
+#endif
+
+#ifndef MAP_HUGE_MASK
+#define MAP_HUGE_MASK 0x3f
+#endif
+
 /* Only ia64 requires this */
 #ifdef __ia64__
 #define ADDR (void *)(0x8000000000000000UL)
@@ -58,12 +66,29 @@ static int read_bytes(char *addr)
 	return 0;
 }
 
-int main(void)
+int main(int argc, char **argv)
 {
 	void *addr;
 	int ret;
+	size_t length = LENGTH;
+	int flags = FLAGS;
+	int shift = 0;
+
+	if (argc > 1)
+		length = atol(argv[1]) << 20;
+	if (argc > 2) {
+		shift = atoi(argv[2]);
+		if (shift)
+			flags |= (shift & MAP_HUGE_MASK) << MAP_HUGE_SHIFT;
+	}
+
+	if (shift)
+		printf("%u kB hugepages\n", 1 << shift);
+	else
+		printf("Default size hugepages\n");
+	printf("Mapping %lu Mbytes\n", (unsigned long)length >> 20);
 
-	addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, -1, 0);
+	addr = mmap(ADDR, length, PROTECTION, flags, -1, 0);
 	if (addr == MAP_FAILED) {
 		perror("mmap");
 		exit(1);