Re: [PATCH] selftests/vm: Update max va test to check for high address return.
From: Aneesh Kumar K.V <hidden>
Date: 2018-02-28 08:08:15
Also in:
linux-mm, lkml
"Aneesh Kumar K.V" [off-list ref] writes:
mmap(-1,..) is expected to search from max supported VA top down. It should find an address above ADDR_SWITCH_HINT. Explicitly check for this. Also derefer the address even if we failed the addr check. Signed-off-by: Aneesh Kumar K.V <redacted>
One issue I noticed is how to make this conditional so that we can still run the test on x86 with 4 level page table?
quoted hunk ↗ jump to hunk
--- tools/testing/selftests/vm/va_128TBswitch.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-)diff --git a/tools/testing/selftests/vm/va_128TBswitch.c b/tools/testing/selftests/vm/va_128TBswitch.c index e7fe734c374f..f68fa4bd8179 100644 --- a/tools/testing/selftests/vm/va_128TBswitch.c +++ b/tools/testing/selftests/vm/va_128TBswitch.c@@ -44,6 +44,7 @@ struct testcase { unsigned long flags; const char *msg; unsigned int low_addr_required:1; + unsigned int high_addr_required:1; unsigned int keep_mapped:1; };@@ -108,6 +109,7 @@ static struct testcase testcases[] = { .flags = MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(HIGH_ADDR)", .keep_mapped = 1, + .high_addr_required = 1, }, { .addr = HIGH_ADDR,@@ -115,12 +117,14 @@ static struct testcase testcases[] = { .flags = MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(HIGH_ADDR) again", .keep_mapped = 1, + .high_addr_required = 1, }, { .addr = HIGH_ADDR, .size = 2 * PAGE_SIZE, .flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, .msg = "mmap(HIGH_ADDR, MAP_FIXED)", + .high_addr_required = 1, }, { .addr = (void *) -1,@@ -128,12 +132,14 @@ static struct testcase testcases[] = { .flags = MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(-1)", .keep_mapped = 1, + .high_addr_required = 1, }, { .addr = (void *) -1, .size = 2 * PAGE_SIZE, .flags = MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(-1) again", + .high_addr_required = 1, }, { .addr = ((void *)(ADDR_SWITCH_HINT - PAGE_SIZE)),@@ -193,6 +199,7 @@ static struct testcase hugetlb_testcases[] = { .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(HIGH_ADDR, MAP_HUGETLB)", .keep_mapped = 1, + .high_addr_required = 1, }, { .addr = HIGH_ADDR,@@ -200,12 +207,14 @@ static struct testcase hugetlb_testcases[] = { .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(HIGH_ADDR, MAP_HUGETLB) again", .keep_mapped = 1, + .high_addr_required = 1, }, { .addr = HIGH_ADDR, .size = HUGETLB_SIZE, .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, .msg = "mmap(HIGH_ADDR, MAP_FIXED | MAP_HUGETLB)", + .high_addr_required = 1, }, { .addr = (void *) -1,@@ -213,12 +222,14 @@ static struct testcase hugetlb_testcases[] = { .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(-1, MAP_HUGETLB)", .keep_mapped = 1, + .high_addr_required = 1, }, { .addr = (void *) -1, .size = HUGETLB_SIZE, .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS, .msg = "mmap(-1, MAP_HUGETLB) again", + .high_addr_required = 1, }, { .addr = (void *)(ADDR_SWITCH_HINT - PAGE_SIZE),@@ -257,14 +268,16 @@ static int run_test(struct testcase *test, int count) if (t->low_addr_required && p >= (void *)(ADDR_SWITCH_HINT)) { printf("FAILED\n"); ret = 1; - } else { - /* - * Do a dereference of the address returned so that we catch - * bugs in page fault handling - */ - memset(p, 0, t->size); + } else if (t->high_addr_required && p < (void *)(ADDR_SWITCH_HINT)) { + printf("FAILED\n"); + ret = 1; + } else printf("OK\n"); - } + /* + * Do a dereference of the address returned so that we catch + * bugs in page fault handling + */ + memset(p, 0, t->size); if (!t->keep_mapped) munmap(p, t->size); }-- 2.14.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>