Re: selftests: mincore: mincore_selftest fails only on qemu-armv7

From: Ricardo Cañuelo
Date: Mon May 15 2023 - 08:32:48 EST


Hi all,

On 15/5/23 13:51, Dan Carpenter wrote:
The test is wrong. It doesn't accept -EINVAL as a valid failure.

tools/testing/selftests/mincore/mincore_selftest.c
139 TEST(check_huge_pages)
140 {
141 unsigned char vec[1];
142 char *addr;
143 int retval;
144 int page_size;
145
146 page_size = sysconf(_SC_PAGESIZE);
147
148 errno = 0;
149 addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
150 MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
151 -1, 0);
152 if (addr == MAP_FAILED) {
153 if (errno == ENOMEM)

On Armv7 is a 32bit machine so HUGETLB isn't enabled and the errno can
be -EINVAL. It's has returned this for 10 years.

154 SKIP(return, "No huge pages available.");
155 else
156 TH_LOG("mmap error: %s", strerror(errno));
157 }
158 retval = mincore(addr, page_size, vec);
159 ASSERT_EQ(0, retval);

mm/mmap.c
1405 }
1406 } else if (flags & MAP_HUGETLB) {
1407 struct hstate *hs;
1408
1409 hs = hstate_sizelog((flags >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK);
1410 if (!hs)
1411 return -EINVAL;
^^^^^^^^^^^^^^^
hstate_sizelog() return NULL when CONFIG_HUGETLB_PAGE is disabled.

1412
1413 len = ALIGN(len, huge_page_size(hs));

regards,
dan carpenter


Thanks for the tip, Dan. I'll send a patch for it asap.

Cheers,
Ricardo