On Fri, Aug 19, 2022, Vishal Annapurve wrote:
+static bool verify_mem_contents(void *mem, uint32_t size, uint8_t pat)
As per feedback in v1[*], spell out "pattern".
[*] https://lore.kernel.org/all/YtiJx11AZHslcGnN@google.com
+{
- uint8_t *buf = (uint8_t *)mem;
- for (uint32_t i = 0; i < size; i++) {
if (buf[i] != pat)return false;- }
- return true;
+}
+/*
- Add custom implementation for memset to avoid using standard/builtin memset
- which may use features like SSE/GOT that don't work with guest vm execution
- within selftests.
- */
+void *memset(void *mem, int byte, size_t size) +{
- uint8_t *buf = (uint8_t *)mem;
- for (uint32_t i = 0; i < size; i++)
buf[i] = byte;- return buf;
+}
memset(), memcpy(), and memcmp() are safe to use as of commit 6b6f71484bf4 ("KVM: selftests: Implement memcmp(), memcpy(), and memset() for guest use").
Note the "fun" with gcc "optimizing" into infinite recursion... :-)
+static void populate_test_area(void *test_area_base, uint64_t pat) +{
- memset(test_area_base, pat, TEST_AREA_SIZE);
+}
+static void populate_guest_test_mem(void *guest_test_mem, uint64_t pat) +{
- memset(guest_test_mem, pat, GUEST_TEST_MEM_SIZE);
+}
+static bool verify_test_area(void *test_area_base, uint64_t area_pat,
- uint64_t guest_pat)
Again, avoid "pat".
+{
- void *test_area1_base = test_area_base;
- uint64_t test_area1_size = GUEST_TEST_MEM_OFFSET;
- void *guest_test_mem = test_area_base + test_area1_size;
- uint64_t guest_test_size = GUEST_TEST_MEM_SIZE;
- void *test_area2_base = guest_test_mem + guest_test_size;
- uint64_t test_area2_size = (TEST_AREA_SIZE - (GUEST_TEST_MEM_OFFSET +
GUEST_TEST_MEM_SIZE));
This is all amazingly hard to read. AFAICT, the local variables are largely useless. Actually, why even take in @test_area_base, isn't it hardcoded to TEST_AREA_GPA? Then everything except the pattern can be hardcoded.
- return (verify_mem_contents(test_area1_base, test_area1_size, area_pat) &&
verify_mem_contents(guest_test_mem, guest_test_size, guest_pat) &&verify_mem_contents(test_area2_base, test_area2_size, area_pat));+}