Add a shmem memory failure selftest to test the shmem memory failure is correct after modifying shmem return value.
Test that + madvise() call returns 0 when the poisoned shmem page is clean + trigger a SIGBUS when the poisoned shmem page is dirty + trigger another SIGBUS when the poisoned shmem page is fault-in again. Signed-off-by: Lisa Wang <[email protected]> --- tools/testing/selftests/mm/memory-failure.c | 109 +++++++++++++++++++++++++++- 1 file changed, 106 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/mm/memory-failure.c b/tools/testing/selftests/mm/memory-failure.c index 3d9e0b9ffb41..eb3f8d98f6c9 100644 --- a/tools/testing/selftests/mm/memory-failure.c +++ b/tools/testing/selftests/mm/memory-failure.c @@ -30,9 +30,14 @@ enum result_type { MADV_HARD_ANON, MADV_HARD_CLEAN_PAGECACHE, MADV_HARD_DIRTY_PAGECACHE, + MADV_HARD_CLEAN_SHMEM, + MADV_HARD_DIRTY_SHMEM, MADV_SOFT_ANON, MADV_SOFT_CLEAN_PAGECACHE, MADV_SOFT_DIRTY_PAGECACHE, + MADV_SOFT_CLEAN_SHMEM, + MADV_SOFT_DIRTY_SHMEM, + READ_ERROR, }; static jmp_buf signal_jmp_buf; @@ -165,17 +170,21 @@ static void check(struct __test_metadata *_metadata, FIXTURE_DATA(memory_failure case MADV_HARD_CLEAN_PAGECACHE: case MADV_SOFT_CLEAN_PAGECACHE: case MADV_SOFT_DIRTY_PAGECACHE: - /* It is not expected to receive a SIGBUS signal. */ - ASSERT_EQ(setjmp, 0); - + case MADV_SOFT_DIRTY_SHMEM: /* The page content should remain unchanged. */ ASSERT_TRUE(check_memory(vaddr, self->page_size)); + case MADV_HARD_CLEAN_SHMEM: + case MADV_SOFT_CLEAN_SHMEM: + /* It is not expected to receive a SIGBUS signal. */ + ASSERT_EQ(setjmp, 0); /* The backing pfn of addr should have changed. */ ASSERT_NE(pagemap_get_pfn(self->pagemap_fd, vaddr), self->pfn); break; case MADV_HARD_ANON: case MADV_HARD_DIRTY_PAGECACHE: + case MADV_HARD_DIRTY_SHMEM: + case READ_ERROR: /* The SIGBUS signal should have been received. */ ASSERT_EQ(setjmp, 1); @@ -260,6 +269,20 @@ static int prepare_file(const char *fname, unsigned long size) return fd; } +static int prepare_shmem(const char *fname, unsigned long size) +{ + int fd; + + fd = memfd_create(fname, 0); + if (fd < 0) + return -1; + if (ftruncate(fd, size) < 0) { + close(fd); + return -1; + } + return fd; +} + /* Borrowed from mm/gup_longterm.c. */ static int get_fs_type(int fd) { @@ -356,4 +379,84 @@ TEST_F(memory_failure, dirty_pagecache) ASSERT_EQ(close(fd), 0); } +TEST_F(memory_failure, dirty_shmem) +{ + int fd; + char *addr; + int ret; + + fd = prepare_shmem("shmem-file", self->page_size); + if (fd < 0) + SKIP(return, "failed to open test shmem-file.\n"); + + addr = mmap(0, self->page_size, PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if (addr == MAP_FAILED) { + close(fd); + SKIP(return, "mmap failed, not enough memory.\n"); + } + memset(addr, 0xce, self->page_size); + + prepare(_metadata, self, addr); + + ret = sigsetjmp(signal_jmp_buf, 1); + if (ret == 0) + ASSERT_EQ(variant->inject(self, addr), 0); + + if (variant->type == MADV_HARD) { + check(_metadata, self, addr, MADV_HARD_DIRTY_SHMEM, ret); + ret = sigsetjmp(signal_jmp_buf, 1); + if (ret == 0) + FORCE_READ(*addr); + check(_metadata, self, addr, READ_ERROR, ret); + } else { + check(_metadata, self, addr, MADV_SOFT_DIRTY_SHMEM, ret); + } + + ASSERT_EQ(munmap(addr, self->page_size), 0); + + ASSERT_EQ(close(fd), 0); + cleanup(_metadata, self, addr); +} + +TEST_F(memory_failure, clean_shmem) +{ + int fd; + char *addr; + int ret; + + fd = prepare_shmem("shmem-file", self->page_size); + if (fd < 0) + SKIP(return, "failed to open test shmem-file.\n"); + + addr = mmap(0, self->page_size, PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if (addr == MAP_FAILED) { + close(fd); + SKIP(return, "mmap failed, not enough memory.\n"); + } + FORCE_READ(*addr); + + prepare(_metadata, self, addr); + + ret = sigsetjmp(signal_jmp_buf, 1); + if (ret == 0) + ASSERT_EQ(variant->inject(self, addr), 0); + + if (variant->type == MADV_HARD) { + check(_metadata, self, addr, MADV_HARD_CLEAN_SHMEM, ret); + ret = sigsetjmp(signal_jmp_buf, 1); + if (ret == 0) + FORCE_READ(*addr); + check(_metadata, self, addr, READ_ERROR, ret); + } else { + check(_metadata, self, addr, MADV_SOFT_CLEAN_SHMEM, ret); + } + + ASSERT_EQ(munmap(addr, self->page_size), 0); + + ASSERT_EQ(close(fd), 0); + cleanup(_metadata, self, addr); +} + TEST_HARNESS_MAIN -- 2.53.0.1213.gd9a14994de-goog
