The binder allocator selftest was only checking the last page of buffers that ended on a page boundary. Correct the page indexing to account for buffers that are not page-aligned.

Acked-by: Carlos Llamas cmllamas@google.com Signed-off-by: Tiffany Yang ynaffit@google.com --- v4: * Fixed unaligned comment * Collected tags --- drivers/android/binder_alloc_selftest.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c index c88735c54848..de5bd848d042 100644 --- a/drivers/android/binder_alloc_selftest.c +++ b/drivers/android/binder_alloc_selftest.c @@ -142,7 +142,7 @@ static void binder_selftest_free_buf(struct binder_alloc *alloc, for (i = 0; i < BUFFER_NUM; i++) binder_alloc_free_buf(alloc, buffers[seq[i]]);

- for (i = 0; i < end / PAGE_SIZE; i++) { + for (i = 0; i <= (end - 1) / PAGE_SIZE; i++) { /** * Error message on a free page can be false positive * if binder shrinker ran during binder_alloc_free_buf

Store a pointer to the free pages list that the binder allocator should use for a process inside of struct binder_alloc. This change allows binder allocator code to be tested and debugged deterministically while a system is using binder; i.e., without interfering with other binder processes and independently of the shrinker. This is necessary to convert the current binder_alloc_selftest into a kunit test that does not rely on hijacking an existing binder_proc to run.

A binder process's binder_alloc->freelist should not be changed after it is initialized. A sole exception is the process that runs the existing binder_alloc selftest. Its freelist can be temporarily replaced for the duration of the test because it runs as a single thread before any pages can be added to the global binder freelist, and the test frees every page it allocates before dropping the binder_selftest_lock. This exception allows the existing selftest to be used to check for regressions, but it will be dropped when the binder_alloc tests are converted to kunit in a subsequent patch in this series.

Acked-by: Carlos Llamas cmllamas@google.com Signed-off-by: Tiffany Yang ynaffit@google.com --- v4: * Collected tag --- drivers/android/binder_alloc.c | 25 +++++++---- drivers/android/binder_alloc.h | 3 +- drivers/android/binder_alloc_selftest.c | 59 ++++++++++++++++++++----- 3 files changed, 67 insertions(+), 20 deletions(-)

diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index fcfaf1b899c8..2e89f9127883 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -26,7 +26,7 @@ #include "binder_alloc.h" #include "binder_trace.h"

-struct list_lru binder_freelist; +static struct list_lru binder_freelist;

static DEFINE_MUTEX(binder_alloc_mmap_lock);

@@ -210,7 +210,7 @@ static void binder_lru_freelist_add(struct binder_alloc *alloc,

trace_binder_free_lru_start(alloc, index);

- ret = list_lru_add(&binder_freelist, + ret = list_lru_add(alloc->freelist, page_to_lru(page), page_to_nid(page), NULL); @@ -409,7 +409,7 @@ static void binder_lru_freelist_del(struct binder_alloc *alloc, if (page) { trace_binder_alloc_lru_start(alloc, index);

- on_lru = list_lru_del(&binder_freelist, + on_lru = list_lru_del(alloc->freelist, page_to_lru(page), page_to_nid(page), NULL); @@ -1007,7 +1007,7 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc) if (!page) continue;

- on_lru = list_lru_del(&binder_freelist, + on_lru = list_lru_del(alloc->freelist, page_to_lru(page), page_to_nid(page), NULL); @@ -1229,6 +1229,17 @@ binder_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)

static struct shrinker *binder_shrinker;

+static void __binder_alloc_init(struct binder_alloc *alloc, + struct list_lru *freelist) +{ + alloc->pid = current->group_leader->pid; + alloc->mm = current->mm; + mmgrab(alloc->mm); + mutex_init(&alloc->mutex); + INIT_LIST_HEAD(&alloc->buffers); + alloc->freelist = freelist; +} + /** * binder_alloc_init() - called by binder_open() for per-proc initialization * @alloc: binder_alloc for this proc @@ -1238,11 +1249,7 @@ static struct shrinker *binder_shrinker; */ void binder_alloc_init(struct binder_alloc *alloc) { - alloc->pid = current->group_leader->pid; - alloc->mm = current->mm; - mmgrab(alloc->mm); - mutex_init(&alloc->mutex); - INIT_LIST_HEAD(&alloc->buffers); + __binder_alloc_init(alloc, &binder_freelist); }

int binder_alloc_shrinker_init(void) diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h index feecd7414241..aa05a9df1360 100644 --- a/drivers/android/binder_alloc.h +++ b/drivers/android/binder_alloc.h @@ -15,7 +15,6 @@ #include <linux/list_lru.h> #include <uapi/linux/android/binder.h>

-extern struct list_lru binder_freelist; struct binder_transaction;

/** @@ -91,6 +90,7 @@ static inline struct list_head *page_to_lru(struct page *p) * @free_async_space: VA space available for async buffers. This is * initialized at mmap time to 1/2 the full VA space * @pages: array of struct page * + * @freelist: lru list to use for free pages (invariant after init) * @buffer_size: size of address space specified via mmap * @pid: pid for associated binder_proc (invariant after init) * @pages_high: high watermark of offset in @pages @@ -113,6 +113,7 @@ struct binder_alloc { struct rb_root allocated_buffers; size_t free_async_space; struct page **pages; + struct list_lru *freelist; size_t buffer_size; int pid; size_t pages_high; diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c index de5bd848d042..8b18b22aa3de 100644 --- a/drivers/android/binder_alloc_selftest.c +++ b/drivers/android/binder_alloc_selftest.c @@ -8,8 +8,9 @@

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

-#include <linux/mm_types.h> #include <linux/err.h> +#include <linux/list_lru.h> +#include <linux/mm_types.h> #include "binder_alloc.h"

#define BUFFER_NUM 5 @@ -18,6 +19,7 @@ static bool binder_selftest_run = true; static int binder_selftest_failures; static DEFINE_MUTEX(binder_selftest_lock); +static struct list_lru binder_selftest_freelist;

/** * enum buf_end_align_type - Page alignment of a buffer @@ -143,11 +145,6 @@ static void binder_selftest_free_buf(struct binder_alloc *alloc, binder_alloc_free_buf(alloc, buffers[seq[i]]);

for (i = 0; i <= (end - 1) / PAGE_SIZE; i++) { - /** - * Error message on a free page can be false positive - * if binder shrinker ran during binder_alloc_free_buf - * calls above. - */ if (list_empty(page_to_lru(alloc->pages[i]))) { pr_err_size_seq(sizes, seq); pr_err("expect lru but is %s at page index %d\n", @@ -162,8 +159,8 @@ static void binder_selftest_free_page(struct binder_alloc *alloc) int i; unsigned long count;

- while ((count = list_lru_count(&binder_freelist))) { - list_lru_walk(&binder_freelist, binder_alloc_free_page, + while ((count = list_lru_count(&binder_selftest_freelist))) { + list_lru_walk(&binder_selftest_freelist, binder_alloc_free_page, NULL, count); }

@@ -187,7 +184,7 @@ static void binder_selftest_alloc_free(struct binder_alloc *alloc,

/* Allocate from lru. */ binder_selftest_alloc_buf(alloc, buffers, sizes, seq); - if (list_lru_count(&binder_freelist)) + if (list_lru_count(&binder_selftest_freelist)) pr_err("lru list should be empty but is not\n");

binder_selftest_free_buf(alloc, buffers, sizes, seq, end); @@ -275,6 +272,20 @@ static void binder_selftest_alloc_offset(struct binder_alloc *alloc, } }

+int binder_selftest_alloc_get_page_count(struct binder_alloc *alloc) +{ + struct page *page; + int allocated = 0; + int i; + + for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { + page = alloc->pages[i]; + if (page) + allocated++; + } + return allocated; +} + /** * binder_selftest_alloc() - Test alloc and free of buffer pages. * @alloc: Pointer to alloc struct. @@ -286,6 +297,7 @@ static void binder_selftest_alloc_offset(struct binder_alloc *alloc, */ void binder_selftest_alloc(struct binder_alloc *alloc) { + struct list_lru *prev_freelist; size_t end_offset[BUFFER_NUM];

if (!binder_selftest_run) @@ -293,14 +305,41 @@ void binder_selftest_alloc(struct binder_alloc *alloc) mutex_lock(&binder_selftest_lock); if (!binder_selftest_run || !alloc->mapped) goto done; + + prev_freelist = alloc->freelist; + + /* + * It is not safe to modify this process's alloc->freelist if it has any + * pages on a freelist. Since the test runs before any binder ioctls can + * be dealt with, none of its pages should be allocated yet. + */ + if (binder_selftest_alloc_get_page_count(alloc)) { + pr_err("process has existing alloc state\n"); + goto cleanup; + } + + if (list_lru_init(&binder_selftest_freelist)) { + pr_err("failed to init test freelist\n"); + goto cleanup; + } + + alloc->freelist = &binder_selftest_freelist; + pr_info("STARTED\n"); binder_selftest_alloc_offset(alloc, end_offset, 0); - binder_selftest_run = false; if (binder_selftest_failures > 0) pr_info("%d tests FAILED\n", binder_selftest_failures); else pr_info("PASSED\n");

+ if (list_lru_count(&binder_selftest_freelist)) + pr_err("expect test freelist to be empty\n"); + +cleanup: + /* Even if we didn't run the test, it's no longer thread-safe. */ + binder_selftest_run = false; + alloc->freelist = prev_freelist; + list_lru_destroy(&binder_selftest_freelist); done: mutex_unlock(&binder_selftest_lock); }

Tests can allocate from virtual memory using kunit_vm_mmap(), which transparently creates and attaches an mm_struct to the test runner if one is not already attached. This is suitable for most cases, except for when the code under test must access a task's mm before performing an mmap. Expose kunit_attach_mm() as part of the interface for those cases. This does not change the existing behavior.

Cc: David Gow davidgow@google.com Reviewed-by: Carlos Llamas cmllamas@google.com Reviewed-by: Kees Cook kees@kernel.org Signed-off-by: Tiffany Yang ynaffit@google.com --- v4: * Collected tags --- include/kunit/test.h | 12 ++++++++++++ lib/kunit/user_alloc.c | 4 ++-- 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/include/kunit/test.h b/include/kunit/test.h index 39c768f87dc9..d958ee53050e 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -531,6 +531,18 @@ static inline char *kunit_kstrdup(struct kunit *test, const char *str, gfp_t gfp */ const char *kunit_kstrdup_const(struct kunit *test, const char *str, gfp_t gfp);

+/** + * kunit_attach_mm() - Create and attach a new mm if it doesn't already exist. + * + * Allocates a &struct mm_struct and attaches it to @current. In most cases, call + * kunit_vm_mmap() without calling kunit_attach_mm() directly. Only necessary when + * code under test accesses the mm before executing the mmap (e.g., to perform + * additional initialization beforehand). + * + * Return: 0 on success, -errno on failure. + */ +int kunit_attach_mm(void); + /** * kunit_vm_mmap() - Allocate KUnit-tracked vm_mmap() area * @test: The test context object. diff --git a/lib/kunit/user_alloc.c b/lib/kunit/user_alloc.c index 46951be018be..b8cac765e620 100644 --- a/lib/kunit/user_alloc.c +++ b/lib/kunit/user_alloc.c @@ -22,8 +22,7 @@ struct kunit_vm_mmap_params { unsigned long offset; };

-/* Create and attach a new mm if it doesn't already exist. */ -static int kunit_attach_mm(void) +int kunit_attach_mm(void) { struct mm_struct *mm;

@@ -49,6 +48,7 @@ static int kunit_attach_mm(void)

return 0; } +EXPORT_SYMBOL_GPL(kunit_attach_mm);

static int kunit_vm_mmap_init(struct kunit_resource *res, void *context) {

Convert the existing binder_alloc_selftest tests into KUnit tests. These tests allocate and free an exhaustive combination of buffers with various sizes and alignments. This change allows them to be run without blocking or otherwise interfering with other processes in binder.

This test is refactored into more meaningful cases in the subsequent patch.

Acked-by: Carlos Llamas cmllamas@google.com Signed-off-by: Tiffany Yang ynaffit@google.com --- v2: * Fix build warning Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202506281837.hReNHJjO-lkp@intel.com/ v4: * Collected tag --- drivers/android/Kconfig | 10 - drivers/android/Makefile | 1 - drivers/android/binder.c | 5 - drivers/android/binder_alloc.c | 3 + drivers/android/binder_alloc.h | 5 - drivers/android/binder_alloc_selftest.c | 345 --------------------- drivers/android/tests/binder_alloc_kunit.c | 279 +++++++++++++++++ 7 files changed, 282 insertions(+), 366 deletions(-) delete mode 100644 drivers/android/binder_alloc_selftest.c

diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig index b1bc7183366c..5b3b8041f827 100644 --- a/drivers/android/Kconfig +++ b/drivers/android/Kconfig @@ -37,16 +37,6 @@ config ANDROID_BINDER_DEVICES created. Each binder device has its own context manager, and is therefore logically separated from the other devices.

-config ANDROID_BINDER_IPC_SELFTEST - bool "Android Binder IPC Driver Selftest" - depends on ANDROID_BINDER_IPC - help - This feature allows binder selftest to run. - - Binder selftest checks the allocation and free of binder buffers - exhaustively with combinations of various buffer sizes and - alignments. - config ANDROID_BINDER_ALLOC_KUNIT_TEST tristate "KUnit Tests for Android Binder Alloc" if !KUNIT_ALL_TESTS depends on ANDROID_BINDER_IPC && KUNIT diff --git a/drivers/android/Makefile b/drivers/android/Makefile index 74d02a335d4e..c5d47be0276c 100644 --- a/drivers/android/Makefile +++ b/drivers/android/Makefile @@ -3,5 +3,4 @@ ccflags-y += -I$(src) # needed for trace events

obj-$(CONFIG_ANDROID_BINDERFS) += binderfs.o obj-$(CONFIG_ANDROID_BINDER_IPC) += binder.o binder_alloc.o -obj-$(CONFIG_ANDROID_BINDER_IPC_SELFTEST) += binder_alloc_selftest.o obj-$(CONFIG_ANDROID_BINDER_ALLOC_KUNIT_TEST) += tests/ diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 9dfe90c284fc..7b2653a5d59c 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -5718,11 +5718,6 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) struct binder_thread *thread; void __user *ubuf = (void __user *)arg;

- /*pr_info("binder_ioctl: %d:%d %x %lx\n", - proc->pid, current->pid, cmd, arg);*/ - - binder_selftest_alloc(&proc->alloc); - trace_binder_ioctl(cmd, arg);

ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2); diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index c79e5c6721f0..74a184014fa7 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -701,6 +701,7 @@ struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, out: return buffer; } +EXPORT_SYMBOL_IF_KUNIT(binder_alloc_new_buf);

static unsigned long buffer_start_page(struct binder_buffer *buffer) { @@ -879,6 +880,7 @@ void binder_alloc_free_buf(struct binder_alloc *alloc, binder_free_buf_locked(alloc, buffer); mutex_unlock(&alloc->mutex); } +EXPORT_SYMBOL_IF_KUNIT(binder_alloc_free_buf);

/** * binder_alloc_mmap_handler() - map virtual address space for proc @@ -1217,6 +1219,7 @@ enum lru_status binder_alloc_free_page(struct list_head *item, err_mmget: return LRU_SKIP; } +EXPORT_SYMBOL_IF_KUNIT(binder_alloc_free_page);

static unsigned long binder_shrink_count(struct shrinker *shrink, struct shrink_control *sc) diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h index dc8dce2469a7..bed97c2cad92 100644 --- a/drivers/android/binder_alloc.h +++ b/drivers/android/binder_alloc.h @@ -121,11 +121,6 @@ struct binder_alloc { bool oneway_spam_detected; };

-#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST -void binder_selftest_alloc(struct binder_alloc *alloc); -#else -static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} -#endif enum lru_status binder_alloc_free_page(struct list_head *item, struct list_lru_one *lru, void *cb_arg); diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c deleted file mode 100644 index 8b18b22aa3de..000000000000 --- a/drivers/android/binder_alloc_selftest.c +++ /dev/null @@ -1,345 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* binder_alloc_selftest.c - * - * Android IPC Subsystem - * - * Copyright (C) 2017 Google, Inc. - */ - -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include <linux/err.h> -#include <linux/list_lru.h> -#include <linux/mm_types.h> -#include "binder_alloc.h" - -#define BUFFER_NUM 5 -#define BUFFER_MIN_SIZE (PAGE_SIZE / 8) - -static bool binder_selftest_run = true; -static int binder_selftest_failures; -static DEFINE_MUTEX(binder_selftest_lock); -static struct list_lru binder_selftest_freelist; - -/** - * enum buf_end_align_type - Page alignment of a buffer - * end with regard to the end of the previous buffer. - * - * In the pictures below, buf2 refers to the buffer we - * are aligning. buf1 refers to previous buffer by addr. - * Symbol [ means the start of a buffer, ] means the end - * of a buffer, and | means page boundaries. - */ -enum buf_end_align_type { - /** - * @SAME_PAGE_UNALIGNED: The end of this buffer is on - * the same page as the end of the previous buffer and - * is not page aligned. Examples: - * buf1 ][ buf2 ][ ... - * buf1 ]|[ buf2 ][ ... - */ - SAME_PAGE_UNALIGNED = 0, - /** - * @SAME_PAGE_ALIGNED: When the end of the previous buffer - * is not page aligned, the end of this buffer is on the - * same page as the end of the previous buffer and is page - * aligned. When the previous buffer is page aligned, the - * end of this buffer is aligned to the next page boundary. - * Examples: - * buf1 ][ buf2 ]| ... - * buf1 ]|[ buf2 ]| ... - */ - SAME_PAGE_ALIGNED, - /** - * @NEXT_PAGE_UNALIGNED: The end of this buffer is on - * the page next to the end of the previous buffer and - * is not page aligned. Examples: - * buf1 ][ buf2 | buf2 ][ ... - * buf1 ]|[ buf2 | buf2 ][ ... - */ - NEXT_PAGE_UNALIGNED, - /** - * @NEXT_PAGE_ALIGNED: The end of this buffer is on - * the page next to the end of the previous buffer and - * is page aligned. Examples: - * buf1 ][ buf2 | buf2 ]| ... - * buf1 ]|[ buf2 | buf2 ]| ... - */ - NEXT_PAGE_ALIGNED, - /** - * @NEXT_NEXT_UNALIGNED: The end of this buffer is on - * the page that follows the page after the end of the - * previous buffer and is not page aligned. Examples: - * buf1 ][ buf2 | buf2 | buf2 ][ ... - * buf1 ]|[ buf2 | buf2 | buf2 ][ ... - */ - NEXT_NEXT_UNALIGNED, - /** - * @LOOP_END: The number of enum values in &buf_end_align_type. - * It is used for controlling loop termination. - */ - LOOP_END, -}; - -static void pr_err_size_seq(size_t *sizes, int *seq) -{ - int i; - - pr_err("alloc sizes: "); - for (i = 0; i < BUFFER_NUM; i++) - pr_cont("[%zu]", sizes[i]); - pr_cont("\n"); - pr_err("free seq: "); - for (i = 0; i < BUFFER_NUM; i++) - pr_cont("[%d]", seq[i]); - pr_cont("\n"); -} - -static bool check_buffer_pages_allocated(struct binder_alloc *alloc, - struct binder_buffer *buffer, - size_t size) -{ - unsigned long page_addr; - unsigned long end; - int page_index; - - end = PAGE_ALIGN(buffer->user_data + size); - page_addr = buffer->user_data; - for (; page_addr < end; page_addr += PAGE_SIZE) { - page_index = (page_addr - alloc->vm_start) / PAGE_SIZE; - if (!alloc->pages[page_index] || - !list_empty(page_to_lru(alloc->pages[page_index]))) { - pr_err("expect alloc but is %s at page index %d\n", - alloc->pages[page_index] ? - "lru" : "free", page_index); - return false; - } - } - return true; -} - -static void binder_selftest_alloc_buf(struct binder_alloc *alloc, - struct binder_buffer *buffers[], - size_t *sizes, int *seq) -{ - int i; - - for (i = 0; i < BUFFER_NUM; i++) { - buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0); - if (IS_ERR(buffers[i]) || - !check_buffer_pages_allocated(alloc, buffers[i], - sizes[i])) { - pr_err_size_seq(sizes, seq); - binder_selftest_failures++; - } - } -} - -static void binder_selftest_free_buf(struct binder_alloc *alloc, - struct binder_buffer *buffers[], - size_t *sizes, int *seq, size_t end) -{ - int i; - - for (i = 0; i < BUFFER_NUM; i++) - binder_alloc_free_buf(alloc, buffers[seq[i]]); - - for (i = 0; i <= (end - 1) / PAGE_SIZE; i++) { - if (list_empty(page_to_lru(alloc->pages[i]))) { - pr_err_size_seq(sizes, seq); - pr_err("expect lru but is %s at page index %d\n", - alloc->pages[i] ? "alloc" : "free", i); - binder_selftest_failures++; - } - } -} - -static void binder_selftest_free_page(struct binder_alloc *alloc) -{ - int i; - unsigned long count; - - while ((count = list_lru_count(&binder_selftest_freelist))) { - list_lru_walk(&binder_selftest_freelist, binder_alloc_free_page, - NULL, count); - } - - for (i = 0; i < (alloc->buffer_size / PAGE_SIZE); i++) { - if (alloc->pages[i]) { - pr_err("expect free but is %s at page index %d\n", - list_empty(page_to_lru(alloc->pages[i])) ? - "alloc" : "lru", i); - binder_selftest_failures++; - } - } -} - -static void binder_selftest_alloc_free(struct binder_alloc *alloc, - size_t *sizes, int *seq, size_t end) -{ - struct binder_buffer *buffers[BUFFER_NUM]; - - binder_selftest_alloc_buf(alloc, buffers, sizes, seq); - binder_selftest_free_buf(alloc, buffers, sizes, seq, end); - - /* Allocate from lru. */ - binder_selftest_alloc_buf(alloc, buffers, sizes, seq); - if (list_lru_count(&binder_selftest_freelist)) - pr_err("lru list should be empty but is not\n"); - - binder_selftest_free_buf(alloc, buffers, sizes, seq, end); - binder_selftest_free_page(alloc); -} - -static bool is_dup(int *seq, int index, int val) -{ - int i; - - for (i = 0; i < index; i++) { - if (seq[i] == val) - return true; - } - return false; -} - -/* Generate BUFFER_NUM factorial free orders. */ -static void binder_selftest_free_seq(struct binder_alloc *alloc, - size_t *sizes, int *seq, - int index, size_t end) -{ - int i; - - if (index == BUFFER_NUM) { - binder_selftest_alloc_free(alloc, sizes, seq, end); - return; - } - for (i = 0; i < BUFFER_NUM; i++) { - if (is_dup(seq, index, i)) - continue; - seq[index] = i; - binder_selftest_free_seq(alloc, sizes, seq, index + 1, end); - } -} - -static void binder_selftest_alloc_size(struct binder_alloc *alloc, - size_t *end_offset) -{ - int i; - int seq[BUFFER_NUM] = {0}; - size_t front_sizes[BUFFER_NUM]; - size_t back_sizes[BUFFER_NUM]; - size_t last_offset, offset = 0; - - for (i = 0; i < BUFFER_NUM; i++) { - last_offset = offset; - offset = end_offset[i]; - front_sizes[i] = offset - last_offset; - back_sizes[BUFFER_NUM - i - 1] = front_sizes[i]; - } - /* - * Buffers share the first or last few pages. - * Only BUFFER_NUM - 1 buffer sizes are adjustable since - * we need one giant buffer before getting to the last page. - */ - back_sizes[0] += alloc->buffer_size - end_offset[BUFFER_NUM - 1]; - binder_selftest_free_seq(alloc, front_sizes, seq, 0, - end_offset[BUFFER_NUM - 1]); - binder_selftest_free_seq(alloc, back_sizes, seq, 0, alloc->buffer_size); -} - -static void binder_selftest_alloc_offset(struct binder_alloc *alloc, - size_t *end_offset, int index) -{ - int align; - size_t end, prev; - - if (index == BUFFER_NUM) { - binder_selftest_alloc_size(alloc, end_offset); - return; - } - prev = index == 0 ? 0 : end_offset[index - 1]; - end = prev; - - BUILD_BUG_ON(BUFFER_MIN_SIZE * BUFFER_NUM >= PAGE_SIZE); - - for (align = SAME_PAGE_UNALIGNED; align < LOOP_END; align++) { - if (align % 2) - end = ALIGN(end, PAGE_SIZE); - else - end += BUFFER_MIN_SIZE; - end_offset[index] = end; - binder_selftest_alloc_offset(alloc, end_offset, index + 1); - } -} - -int binder_selftest_alloc_get_page_count(struct binder_alloc *alloc) -{ - struct page *page; - int allocated = 0; - int i; - - for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { - page = alloc->pages[i]; - if (page) - allocated++; - } - return allocated; -} - -/** - * binder_selftest_alloc() - Test alloc and free of buffer pages. - * @alloc: Pointer to alloc struct. - * - * Allocate BUFFER_NUM buffers to cover all page alignment cases, - * then free them in all orders possible. Check that pages are - * correctly allocated, put onto lru when buffers are freed, and - * are freed when binder_alloc_free_page is called. - */ -void binder_selftest_alloc(struct binder_alloc *alloc) -{ - struct list_lru *prev_freelist; - size_t end_offset[BUFFER_NUM]; - - if (!binder_selftest_run) - return; - mutex_lock(&binder_selftest_lock); - if (!binder_selftest_run || !alloc->mapped) - goto done; - - prev_freelist = alloc->freelist; - - /* - * It is not safe to modify this process's alloc->freelist if it has any - * pages on a freelist. Since the test runs before any binder ioctls can - * be dealt with, none of its pages should be allocated yet. - */ - if (binder_selftest_alloc_get_page_count(alloc)) { - pr_err("process has existing alloc state\n"); - goto cleanup; - } - - if (list_lru_init(&binder_selftest_freelist)) { - pr_err("failed to init test freelist\n"); - goto cleanup; - } - - alloc->freelist = &binder_selftest_freelist; - - pr_info("STARTED\n"); - binder_selftest_alloc_offset(alloc, end_offset, 0); - if (binder_selftest_failures > 0) - pr_info("%d tests FAILED\n", binder_selftest_failures); - else - pr_info("PASSED\n"); - - if (list_lru_count(&binder_selftest_freelist)) - pr_err("expect test freelist to be empty\n"); - -cleanup: - /* Even if we didn't run the test, it's no longer thread-safe. */ - binder_selftest_run = false; - alloc->freelist = prev_freelist; - list_lru_destroy(&binder_selftest_freelist); -done: - mutex_unlock(&binder_selftest_lock); -} diff --git a/drivers/android/tests/binder_alloc_kunit.c b/drivers/android/tests/binder_alloc_kunit.c index 5e49078c9b23..2f6077e96ae6 100644 --- a/drivers/android/tests/binder_alloc_kunit.c +++ b/drivers/android/tests/binder_alloc_kunit.c @@ -24,6 +24,265 @@ MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");

#define BINDER_MMAP_SIZE SZ_128K

+#define BUFFER_NUM 5 +#define BUFFER_MIN_SIZE (PAGE_SIZE / 8) + +static int binder_alloc_test_failures; + +/** + * enum buf_end_align_type - Page alignment of a buffer + * end with regard to the end of the previous buffer. + * + * In the pictures below, buf2 refers to the buffer we + * are aligning. buf1 refers to previous buffer by addr. + * Symbol [ means the start of a buffer, ] means the end + * of a buffer, and | means page boundaries. + */ +enum buf_end_align_type { + /** + * @SAME_PAGE_UNALIGNED: The end of this buffer is on + * the same page as the end of the previous buffer and + * is not page aligned. Examples: + * buf1 ][ buf2 ][ ... + * buf1 ]|[ buf2 ][ ... + */ + SAME_PAGE_UNALIGNED = 0, + /** + * @SAME_PAGE_ALIGNED: When the end of the previous buffer + * is not page aligned, the end of this buffer is on the + * same page as the end of the previous buffer and is page + * aligned. When the previous buffer is page aligned, the + * end of this buffer is aligned to the next page boundary. + * Examples: + * buf1 ][ buf2 ]| ... + * buf1 ]|[ buf2 ]| ... + */ + SAME_PAGE_ALIGNED, + /** + * @NEXT_PAGE_UNALIGNED: The end of this buffer is on + * the page next to the end of the previous buffer and + * is not page aligned. Examples: + * buf1 ][ buf2 | buf2 ][ ... + * buf1 ]|[ buf2 | buf2 ][ ... + */ + NEXT_PAGE_UNALIGNED, + /** + * @NEXT_PAGE_ALIGNED: The end of this buffer is on + * the page next to the end of the previous buffer and + * is page aligned. Examples: + * buf1 ][ buf2 | buf2 ]| ... + * buf1 ]|[ buf2 | buf2 ]| ... + */ + NEXT_PAGE_ALIGNED, + /** + * @NEXT_NEXT_UNALIGNED: The end of this buffer is on + * the page that follows the page after the end of the + * previous buffer and is not page aligned. Examples: + * buf1 ][ buf2 | buf2 | buf2 ][ ... + * buf1 ]|[ buf2 | buf2 | buf2 ][ ... + */ + NEXT_NEXT_UNALIGNED, + /** + * @LOOP_END: The number of enum values in &buf_end_align_type. + * It is used for controlling loop termination. + */ + LOOP_END, +}; + +static void pr_err_size_seq(struct kunit *test, size_t *sizes, int *seq) +{ + int i; + + kunit_err(test, "alloc sizes: "); + for (i = 0; i < BUFFER_NUM; i++) + pr_cont("[%zu]", sizes[i]); + pr_cont("\n"); + kunit_err(test, "free seq: "); + for (i = 0; i < BUFFER_NUM; i++) + pr_cont("[%d]", seq[i]); + pr_cont("\n"); +} + +static bool check_buffer_pages_allocated(struct kunit *test, + struct binder_alloc *alloc, + struct binder_buffer *buffer, + size_t size) +{ + unsigned long page_addr; + unsigned long end; + int page_index; + + end = PAGE_ALIGN(buffer->user_data + size); + page_addr = buffer->user_data; + for (; page_addr < end; page_addr += PAGE_SIZE) { + page_index = (page_addr - alloc->vm_start) / PAGE_SIZE; + if (!alloc->pages[page_index] || + !list_empty(page_to_lru(alloc->pages[page_index]))) { + kunit_err(test, "expect alloc but is %s at page index %d\n", + alloc->pages[page_index] ? + "lru" : "free", page_index); + return false; + } + } + return true; +} + +static void binder_alloc_test_alloc_buf(struct kunit *test, + struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq) +{ + int i; + + for (i = 0; i < BUFFER_NUM; i++) { + buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0); + if (IS_ERR(buffers[i]) || + !check_buffer_pages_allocated(test, alloc, buffers[i], sizes[i])) { + pr_err_size_seq(test, sizes, seq); + binder_alloc_test_failures++; + } + } +} + +static void binder_alloc_test_free_buf(struct kunit *test, + struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq, size_t end) +{ + int i; + + for (i = 0; i < BUFFER_NUM; i++) + binder_alloc_free_buf(alloc, buffers[seq[i]]); + + for (i = 0; i <= (end - 1) / PAGE_SIZE; i++) { + if (list_empty(page_to_lru(alloc->pages[i]))) { + pr_err_size_seq(test, sizes, seq); + kunit_err(test, "expect lru but is %s at page index %d\n", + alloc->pages[i] ? "alloc" : "free", i); + binder_alloc_test_failures++; + } + } +} + +static void binder_alloc_test_free_page(struct kunit *test, + struct binder_alloc *alloc) +{ + unsigned long count; + int i; + + while ((count = list_lru_count(alloc->freelist))) { + list_lru_walk(alloc->freelist, binder_alloc_free_page, + NULL, count); + } + + for (i = 0; i < (alloc->buffer_size / PAGE_SIZE); i++) { + if (alloc->pages[i]) { + kunit_err(test, "expect free but is %s at page index %d\n", + list_empty(page_to_lru(alloc->pages[i])) ? + "alloc" : "lru", i); + binder_alloc_test_failures++; + } + } +} + +static void binder_alloc_test_alloc_free(struct kunit *test, + struct binder_alloc *alloc, + size_t *sizes, int *seq, size_t end) +{ + struct binder_buffer *buffers[BUFFER_NUM]; + + binder_alloc_test_alloc_buf(test, alloc, buffers, sizes, seq); + binder_alloc_test_free_buf(test, alloc, buffers, sizes, seq, end); + + /* Allocate from lru. */ + binder_alloc_test_alloc_buf(test, alloc, buffers, sizes, seq); + if (list_lru_count(alloc->freelist)) + kunit_err(test, "lru list should be empty but is not\n"); + + binder_alloc_test_free_buf(test, alloc, buffers, sizes, seq, end); + binder_alloc_test_free_page(test, alloc); +} + +static bool is_dup(int *seq, int index, int val) +{ + int i; + + for (i = 0; i < index; i++) { + if (seq[i] == val) + return true; + } + return false; +} + +/* Generate BUFFER_NUM factorial free orders. */ +static void permute_frees(struct kunit *test, struct binder_alloc *alloc, + size_t *sizes, int *seq, int index, size_t end) +{ + int i; + + if (index == BUFFER_NUM) { + binder_alloc_test_alloc_free(test, alloc, sizes, seq, end); + return; + } + for (i = 0; i < BUFFER_NUM; i++) { + if (is_dup(seq, index, i)) + continue; + seq[index] = i; + permute_frees(test, alloc, sizes, seq, index + 1, end); + } +} + +static void gen_buf_sizes(struct kunit *test, struct binder_alloc *alloc, + size_t *end_offset) +{ + size_t last_offset, offset = 0; + size_t front_sizes[BUFFER_NUM]; + size_t back_sizes[BUFFER_NUM]; + int seq[BUFFER_NUM] = {0}; + int i; + + for (i = 0; i < BUFFER_NUM; i++) { + last_offset = offset; + offset = end_offset[i]; + front_sizes[i] = offset - last_offset; + back_sizes[BUFFER_NUM - i - 1] = front_sizes[i]; + } + /* + * Buffers share the first or last few pages. + * Only BUFFER_NUM - 1 buffer sizes are adjustable since + * we need one giant buffer before getting to the last page. + */ + back_sizes[0] += alloc->buffer_size - end_offset[BUFFER_NUM - 1]; + permute_frees(test, alloc, front_sizes, seq, 0, + end_offset[BUFFER_NUM - 1]); + permute_frees(test, alloc, back_sizes, seq, 0, alloc->buffer_size); +} + +static void gen_buf_offsets(struct kunit *test, struct binder_alloc *alloc, + size_t *end_offset, int index) +{ + size_t end, prev; + int align; + + if (index == BUFFER_NUM) { + gen_buf_sizes(test, alloc, end_offset); + return; + } + prev = index == 0 ? 0 : end_offset[index - 1]; + end = prev; + + BUILD_BUG_ON(BUFFER_MIN_SIZE * BUFFER_NUM >= PAGE_SIZE); + + for (align = SAME_PAGE_UNALIGNED; align < LOOP_END; align++) { + if (align % 2) + end = ALIGN(end, PAGE_SIZE); + else + end += BUFFER_MIN_SIZE; + end_offset[index] = end; + gen_buf_offsets(test, alloc, end_offset, index + 1); + } +} + struct binder_alloc_test { struct binder_alloc alloc; struct list_lru binder_test_freelist; @@ -59,6 +318,25 @@ static void binder_alloc_test_mmap(struct kunit *test) KUNIT_EXPECT_TRUE(test, list_is_last(&buf->entry, &alloc->buffers)); }

+/** + * binder_alloc_exhaustive_test() - Exhaustively test alloc and free of buffer pages. + * @test: The test context object. + * + * Allocate BUFFER_NUM buffers to cover all page alignment cases, + * then free them in all orders possible. Check that pages are + * correctly allocated, put onto lru when buffers are freed, and + * are freed when binder_alloc_free_page() is called. + */ +static void binder_alloc_exhaustive_test(struct kunit *test) +{ + struct binder_alloc_test *priv = test->priv; + size_t end_offset[BUFFER_NUM]; + + gen_buf_offsets(test, &priv->alloc, end_offset, 0); + + KUNIT_EXPECT_EQ(test, binder_alloc_test_failures, 0); +} + /* ===== End test cases ===== */

static void binder_alloc_test_vma_close(struct vm_area_struct *vma) @@ -152,6 +430,7 @@ static void binder_alloc_test_exit(struct kunit *test) static struct kunit_case binder_alloc_test_cases[] = { KUNIT_CASE(binder_alloc_test_init_freelist), KUNIT_CASE(binder_alloc_test_mmap), + KUNIT_CASE(binder_alloc_exhaustive_test), {} };

Each case tested by the binder allocator test is defined by 3 parameters: the end alignment type of each requested buffer allocation, whether those buffers share the front or back pages of the allotted address space, and the order in which those buffers should be released. The alignment type represents how a binder buffer may be laid out within or across page boundaries and relative to other buffers, and it's used along with whether the buffers cover part (sharing the front pages) of or all (sharing the back pages) of the vma to calculate the sizes passed into each test.

binder_alloc_test_alloc recursively generates each possible arrangement of alignment types and then tests that the binder_alloc code tracks pages correctly when those buffers are allocated and then freed in every possible order at both ends of the address space. While they provide comprehensive coverage, they are poor candidates to be represented as KUnit test cases, which must be statically enumerated. For 5 buffers and 5 end alignment types, the test case array would have 750,000 entries. This change structures the recursive calls into meaningful test cases so that failures are easier to interpret.

Cc: Kees Cook kees@kernel.org Acked-by: Carlos Llamas cmllamas@google.com Signed-off-by: Tiffany Yang ynaffit@google.com --- v2: * Fix build warning Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202506281959.hfOTIUjS-lkp@intel.com/ v4: * Replace snprintf with seq_buf functions * Collected tag --- drivers/android/tests/binder_alloc_kunit.c | 226 ++++++++++++++++----- 1 file changed, 175 insertions(+), 51 deletions(-)

diff --git a/drivers/android/tests/binder_alloc_kunit.c b/drivers/android/tests/binder_alloc_kunit.c index 2f6077e96ae6..9b884d977f76 100644 --- a/drivers/android/tests/binder_alloc_kunit.c +++ b/drivers/android/tests/binder_alloc_kunit.c @@ -15,6 +15,7 @@ #include <linux/fs.h> #include <linux/mm.h> #include <linux/mman.h> +#include <linux/seq_buf.h> #include <linux/sizes.h>

#include "../binder_alloc.h" @@ -27,7 +28,16 @@ MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING"); #define BUFFER_NUM 5 #define BUFFER_MIN_SIZE (PAGE_SIZE / 8)

-static int binder_alloc_test_failures; +#define FREESEQ_BUFLEN ((3 * BUFFER_NUM) + 1) + +#define ALIGN_TYPE_STRLEN (12) + +#define ALIGNMENTS_BUFLEN (((ALIGN_TYPE_STRLEN + 6) * BUFFER_NUM) + 1) + +#define PRINT_ALL_CASES (0) + +/* 5^5 alignment combinations * 2 places to share pages * 5! free sequences */ +#define TOTAL_EXHAUSTIVE_CASES (3125 * 2 * 120)

/** * enum buf_end_align_type - Page alignment of a buffer @@ -89,18 +99,42 @@ enum buf_end_align_type { LOOP_END, };

-static void pr_err_size_seq(struct kunit *test, size_t *sizes, int *seq) +static const char *const buf_end_align_type_strs[LOOP_END] = { + [SAME_PAGE_UNALIGNED] = "SP_UNALIGNED", + [SAME_PAGE_ALIGNED] = " SP_ALIGNED ", + [NEXT_PAGE_UNALIGNED] = "NP_UNALIGNED", + [NEXT_PAGE_ALIGNED] = " NP_ALIGNED ", + [NEXT_NEXT_UNALIGNED] = "NN_UNALIGNED", +}; + +struct binder_alloc_test_case_info { + char alignments[ALIGNMENTS_BUFLEN]; + struct seq_buf alignments_sb; + size_t *buffer_sizes; + int *free_sequence; + bool front_pages; +}; + +static void stringify_free_seq(struct kunit *test, int *seq, struct seq_buf *sb) { int i;

- kunit_err(test, "alloc sizes: "); for (i = 0; i < BUFFER_NUM; i++) - pr_cont("[%zu]", sizes[i]); - pr_cont("\n"); - kunit_err(test, "free seq: "); + seq_buf_printf(sb, "[%d]", seq[i]); + + KUNIT_EXPECT_FALSE(test, seq_buf_has_overflowed(sb)); +} + +static void stringify_alignments(struct kunit *test, int *alignments, + struct seq_buf *sb) +{ + int i; + for (i = 0; i < BUFFER_NUM; i++) - pr_cont("[%d]", seq[i]); - pr_cont("\n"); + seq_buf_printf(sb, "[ %d:%s ]", i, + buf_end_align_type_strs[alignments[i]]); + + KUNIT_EXPECT_FALSE(test, seq_buf_has_overflowed(sb)); }

static bool check_buffer_pages_allocated(struct kunit *test, @@ -127,28 +161,30 @@ static bool check_buffer_pages_allocated(struct kunit *test, return true; }

-static void binder_alloc_test_alloc_buf(struct kunit *test, - struct binder_alloc *alloc, - struct binder_buffer *buffers[], - size_t *sizes, int *seq) +static unsigned long binder_alloc_test_alloc_buf(struct kunit *test, + struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq) { + unsigned long failures = 0; int i;

for (i = 0; i < BUFFER_NUM; i++) { buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0); if (IS_ERR(buffers[i]) || - !check_buffer_pages_allocated(test, alloc, buffers[i], sizes[i])) { - pr_err_size_seq(test, sizes, seq); - binder_alloc_test_failures++; - } + !check_buffer_pages_allocated(test, alloc, buffers[i], sizes[i])) + failures++; } + + return failures; }

-static void binder_alloc_test_free_buf(struct kunit *test, - struct binder_alloc *alloc, - struct binder_buffer *buffers[], - size_t *sizes, int *seq, size_t end) +static unsigned long binder_alloc_test_free_buf(struct kunit *test, + struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq, size_t end) { + unsigned long failures = 0; int i;

for (i = 0; i < BUFFER_NUM; i++) @@ -156,17 +192,19 @@ static void binder_alloc_test_free_buf(struct kunit *test,

for (i = 0; i <= (end - 1) / PAGE_SIZE; i++) { if (list_empty(page_to_lru(alloc->pages[i]))) { - pr_err_size_seq(test, sizes, seq); kunit_err(test, "expect lru but is %s at page index %d\n", alloc->pages[i] ? "alloc" : "free", i); - binder_alloc_test_failures++; + failures++; } } + + return failures; }

-static void binder_alloc_test_free_page(struct kunit *test, - struct binder_alloc *alloc) +static unsigned long binder_alloc_test_free_page(struct kunit *test, + struct binder_alloc *alloc) { + unsigned long failures = 0; unsigned long count; int i;

@@ -180,27 +218,70 @@ static void binder_alloc_test_free_page(struct kunit *test, kunit_err(test, "expect free but is %s at page index %d\n", list_empty(page_to_lru(alloc->pages[i])) ? "alloc" : "lru", i); - binder_alloc_test_failures++; + failures++; } } + + return failures; }

-static void binder_alloc_test_alloc_free(struct kunit *test, +/* Executes one full test run for the given test case. */ +static bool binder_alloc_test_alloc_free(struct kunit *test, struct binder_alloc *alloc, - size_t *sizes, int *seq, size_t end) + struct binder_alloc_test_case_info *tc, + size_t end) { + unsigned long pages = PAGE_ALIGN(end) / PAGE_SIZE; struct binder_buffer *buffers[BUFFER_NUM]; - - binder_alloc_test_alloc_buf(test, alloc, buffers, sizes, seq); - binder_alloc_test_free_buf(test, alloc, buffers, sizes, seq, end); + unsigned long failures; + bool failed = false; + + failures = binder_alloc_test_alloc_buf(test, alloc, buffers, + tc->buffer_sizes, + tc->free_sequence); + failed = failed || failures; + KUNIT_EXPECT_EQ_MSG(test, failures, 0, + "Initial allocation failed: %lu/%u buffers with errors", + failures, BUFFER_NUM); + + failures = binder_alloc_test_free_buf(test, alloc, buffers, + tc->buffer_sizes, + tc->free_sequence, end); + failed = failed || failures; + KUNIT_EXPECT_EQ_MSG(test, failures, 0, + "Initial buffers not freed correctly: %lu/%lu pages not on lru list", + failures, pages);

/* Allocate from lru. */ - binder_alloc_test_alloc_buf(test, alloc, buffers, sizes, seq); - if (list_lru_count(alloc->freelist)) - kunit_err(test, "lru list should be empty but is not\n"); - - binder_alloc_test_free_buf(test, alloc, buffers, sizes, seq, end); - binder_alloc_test_free_page(test, alloc); + failures = binder_alloc_test_alloc_buf(test, alloc, buffers, + tc->buffer_sizes, + tc->free_sequence); + failed = failed || failures; + KUNIT_EXPECT_EQ_MSG(test, failures, 0, + "Reallocation failed: %lu/%u buffers with errors", + failures, BUFFER_NUM); + + failures = list_lru_count(alloc->freelist); + failed = failed || failures; + KUNIT_EXPECT_EQ_MSG(test, failures, 0, + "lru list should be empty after reallocation but still has %lu pages", + failures); + + failures = binder_alloc_test_free_buf(test, alloc, buffers, + tc->buffer_sizes, + tc->free_sequence, end); + failed = failed || failures; + KUNIT_EXPECT_EQ_MSG(test, failures, 0, + "Reallocated buffers not freed correctly: %lu/%lu pages not on lru list", + failures, pages); + + failures = binder_alloc_test_free_page(test, alloc); + failed = failed || failures; + KUNIT_EXPECT_EQ_MSG(test, failures, 0, + "Failed to clean up allocated pages: %lu/%lu pages still installed", + failures, (alloc->buffer_size / PAGE_SIZE)); + + return failed; }

static bool is_dup(int *seq, int index, int val) @@ -216,24 +297,45 @@ static bool is_dup(int *seq, int index, int val)

/* Generate BUFFER_NUM factorial free orders. */ static void permute_frees(struct kunit *test, struct binder_alloc *alloc, - size_t *sizes, int *seq, int index, size_t end) + struct binder_alloc_test_case_info *tc, + unsigned long *runs, unsigned long *failures, + int index, size_t end) { + bool case_failed; int i;

if (index == BUFFER_NUM) { - binder_alloc_test_alloc_free(test, alloc, sizes, seq, end); + DECLARE_SEQ_BUF(freeseq_sb, FREESEQ_BUFLEN); + + case_failed = binder_alloc_test_alloc_free(test, alloc, tc, end); + *runs += 1; + *failures += case_failed; + + if (case_failed || PRINT_ALL_CASES) { + stringify_free_seq(test, tc->free_sequence, + &freeseq_sb); + kunit_err(test, "case %lu: [%s] | %s - %s - %s", *runs, + case_failed ? "FAILED" : "PASSED", + tc->front_pages ? "front" : "back ", + seq_buf_str(&tc->alignments_sb), + seq_buf_str(&freeseq_sb)); + } + return; } for (i = 0; i < BUFFER_NUM; i++) { - if (is_dup(seq, index, i)) + if (is_dup(tc->free_sequence, index, i)) continue; - seq[index] = i; - permute_frees(test, alloc, sizes, seq, index + 1, end); + tc->free_sequence[index] = i; + permute_frees(test, alloc, tc, runs, failures, index + 1, end); } }

-static void gen_buf_sizes(struct kunit *test, struct binder_alloc *alloc, - size_t *end_offset) +static void gen_buf_sizes(struct kunit *test, + struct binder_alloc *alloc, + struct binder_alloc_test_case_info *tc, + size_t *end_offset, unsigned long *runs, + unsigned long *failures) { size_t last_offset, offset = 0; size_t front_sizes[BUFFER_NUM]; @@ -241,31 +343,46 @@ static void gen_buf_sizes(struct kunit *test, struct binder_alloc *alloc, int seq[BUFFER_NUM] = {0}; int i;

+ tc->free_sequence = seq; for (i = 0; i < BUFFER_NUM; i++) { last_offset = offset; offset = end_offset[i]; front_sizes[i] = offset - last_offset; back_sizes[BUFFER_NUM - i - 1] = front_sizes[i]; } + back_sizes[0] += alloc->buffer_size - end_offset[BUFFER_NUM - 1]; + /* * Buffers share the first or last few pages. * Only BUFFER_NUM - 1 buffer sizes are adjustable since * we need one giant buffer before getting to the last page. */ - back_sizes[0] += alloc->buffer_size - end_offset[BUFFER_NUM - 1]; - permute_frees(test, alloc, front_sizes, seq, 0, + tc->front_pages = true; + tc->buffer_sizes = front_sizes; + permute_frees(test, alloc, tc, runs, failures, 0, end_offset[BUFFER_NUM - 1]); - permute_frees(test, alloc, back_sizes, seq, 0, alloc->buffer_size); + + tc->front_pages = false; + tc->buffer_sizes = back_sizes; + permute_frees(test, alloc, tc, runs, failures, 0, alloc->buffer_size); }

static void gen_buf_offsets(struct kunit *test, struct binder_alloc *alloc, - size_t *end_offset, int index) + size_t *end_offset, int *alignments, + unsigned long *runs, unsigned long *failures, + int index) { size_t end, prev; int align;

if (index == BUFFER_NUM) { - gen_buf_sizes(test, alloc, end_offset); + struct binder_alloc_test_case_info tc = {0}; + + seq_buf_init(&tc.alignments_sb, tc.alignments, + ALIGNMENTS_BUFLEN); + stringify_alignments(test, alignments, &tc.alignments_sb); + + gen_buf_sizes(test, alloc, &tc, end_offset, runs, failures); return; } prev = index == 0 ? 0 : end_offset[index - 1]; @@ -279,7 +396,9 @@ static void gen_buf_offsets(struct kunit *test, struct binder_alloc *alloc, else end += BUFFER_MIN_SIZE; end_offset[index] = end; - gen_buf_offsets(test, alloc, end_offset, index + 1); + alignments[index] = align; + gen_buf_offsets(test, alloc, end_offset, alignments, runs, + failures, index + 1); } }

@@ -331,10 +450,15 @@ static void binder_alloc_exhaustive_test(struct kunit *test) { struct binder_alloc_test *priv = test->priv; size_t end_offset[BUFFER_NUM]; + int alignments[BUFFER_NUM]; + unsigned long failures = 0; + unsigned long runs = 0;

- gen_buf_offsets(test, &priv->alloc, end_offset, 0); + gen_buf_offsets(test, &priv->alloc, end_offset, alignments, &runs, + &failures, 0);

- KUNIT_EXPECT_EQ(test, binder_alloc_test_failures, 0); + KUNIT_EXPECT_EQ(test, runs, TOTAL_EXHAUSTIVE_CASES); + KUNIT_EXPECT_EQ(test, failures, 0); }

/* ===== End test cases ===== */