5b24ac2dfd
Size of the 'expect' array in the __report_matches is 1536 bytes, which
is exactly the default frame size warning limit of the xtensa
architecture.
As a result allmodconfig xtensa kernel builds with the gcc that does not
support the compiler plugins (which otherwise would push the said
warning limit to 2K) fail with the following message:
kernel/kcsan/kcsan_test.c:257:1: error: the frame size of 1680 bytes
is larger than 1536 bytes
Fix it by dynamically allocating the 'expect' array.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Marco Elver <elver@google.com>
1619 lines
51 KiB
C
1619 lines
51 KiB
C
// SPDX-License-Identifier: GPL-2.0
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|
/*
|
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* KCSAN test with various race scenarious to test runtime behaviour. Since the
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* interface with which KCSAN's reports are obtained is via the console, this is
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* the output we should verify. For each test case checks the presence (or
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* absence) of generated reports. Relies on 'console' tracepoint to capture
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* reports as they appear in the kernel log.
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*
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* Makes use of KUnit for test organization, and the Torture framework for test
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* thread control.
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*
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* Copyright (C) 2020, Google LLC.
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* Author: Marco Elver <elver@google.com>
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*/
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#define pr_fmt(fmt) "kcsan_test: " fmt
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#include <kunit/test.h>
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#include <linux/atomic.h>
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#include <linux/bitops.h>
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#include <linux/jiffies.h>
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#include <linux/kcsan-checks.h>
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#include <linux/kernel.h>
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#include <linux/mutex.h>
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#include <linux/sched.h>
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#include <linux/seqlock.h>
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#include <linux/spinlock.h>
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#include <linux/string.h>
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#include <linux/timer.h>
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#include <linux/torture.h>
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#include <linux/tracepoint.h>
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#include <linux/types.h>
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#include <trace/events/printk.h>
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#define KCSAN_TEST_REQUIRES(test, cond) do { \
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if (!(cond)) \
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kunit_skip((test), "Test requires: " #cond); \
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} while (0)
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#ifdef CONFIG_CC_HAS_TSAN_COMPOUND_READ_BEFORE_WRITE
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#define __KCSAN_ACCESS_RW(alt) (KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE)
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#else
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#define __KCSAN_ACCESS_RW(alt) (alt)
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#endif
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/* Points to current test-case memory access "kernels". */
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static void (*access_kernels[2])(void);
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static struct task_struct **threads; /* Lists of threads. */
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static unsigned long end_time; /* End time of test. */
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/* Report as observed from console. */
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static struct {
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spinlock_t lock;
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int nlines;
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char lines[3][512];
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} observed = {
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.lock = __SPIN_LOCK_UNLOCKED(observed.lock),
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};
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/* Setup test checking loop. */
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static __no_kcsan inline void
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begin_test_checks(void (*func1)(void), void (*func2)(void))
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{
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kcsan_disable_current();
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/*
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* Require at least as long as KCSAN_REPORT_ONCE_IN_MS, to ensure at
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* least one race is reported.
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*/
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end_time = jiffies + msecs_to_jiffies(CONFIG_KCSAN_REPORT_ONCE_IN_MS + 500);
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/* Signal start; release potential initialization of shared data. */
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smp_store_release(&access_kernels[0], func1);
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smp_store_release(&access_kernels[1], func2);
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}
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/* End test checking loop. */
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static __no_kcsan inline bool
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end_test_checks(bool stop)
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{
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if (!stop && time_before(jiffies, end_time)) {
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/* Continue checking */
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might_sleep();
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return false;
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}
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kcsan_enable_current();
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return true;
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}
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/*
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* Probe for console output: checks if a race was reported, and obtains observed
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* lines of interest.
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*/
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__no_kcsan
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static void probe_console(void *ignore, const char *buf, size_t len)
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{
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unsigned long flags;
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int nlines;
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/*
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* Note that KCSAN reports under a global lock, so we do not risk the
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* possibility of having multiple reports interleaved. If that were the
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* case, we'd expect tests to fail.
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*/
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spin_lock_irqsave(&observed.lock, flags);
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nlines = observed.nlines;
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if (strnstr(buf, "BUG: KCSAN: ", len) && strnstr(buf, "test_", len)) {
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/*
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* KCSAN report and related to the test.
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*
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* The provided @buf is not NUL-terminated; copy no more than
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* @len bytes and let strscpy() add the missing NUL-terminator.
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*/
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strscpy(observed.lines[0], buf, min(len + 1, sizeof(observed.lines[0])));
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nlines = 1;
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} else if ((nlines == 1 || nlines == 2) && strnstr(buf, "bytes by", len)) {
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strscpy(observed.lines[nlines++], buf, min(len + 1, sizeof(observed.lines[0])));
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if (strnstr(buf, "race at unknown origin", len)) {
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if (WARN_ON(nlines != 2))
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goto out;
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/* No second line of interest. */
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strcpy(observed.lines[nlines++], "<none>");
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}
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}
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out:
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WRITE_ONCE(observed.nlines, nlines); /* Publish new nlines. */
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spin_unlock_irqrestore(&observed.lock, flags);
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}
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/* Check if a report related to the test exists. */
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__no_kcsan
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static bool report_available(void)
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{
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return READ_ONCE(observed.nlines) == ARRAY_SIZE(observed.lines);
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}
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/* Report information we expect in a report. */
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struct expect_report {
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/* Access information of both accesses. */
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struct {
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void *fn; /* Function pointer to expected function of top frame. */
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void *addr; /* Address of access; unchecked if NULL. */
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size_t size; /* Size of access; unchecked if @addr is NULL. */
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int type; /* Access type, see KCSAN_ACCESS definitions. */
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} access[2];
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};
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/* Check observed report matches information in @r. */
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__no_kcsan
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static bool __report_matches(const struct expect_report *r)
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{
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const bool is_assert = (r->access[0].type | r->access[1].type) & KCSAN_ACCESS_ASSERT;
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bool ret = false;
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unsigned long flags;
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typeof(*observed.lines) *expect;
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const char *end;
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char *cur;
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int i;
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/* Doubled-checked locking. */
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if (!report_available())
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return false;
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expect = kmalloc(sizeof(observed.lines), GFP_KERNEL);
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if (WARN_ON(!expect))
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return false;
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/* Generate expected report contents. */
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/* Title */
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cur = expect[0];
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end = &expect[0][sizeof(expect[0]) - 1];
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cur += scnprintf(cur, end - cur, "BUG: KCSAN: %s in ",
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is_assert ? "assert: race" : "data-race");
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if (r->access[1].fn) {
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char tmp[2][64];
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int cmp;
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/* Expect lexographically sorted function names in title. */
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scnprintf(tmp[0], sizeof(tmp[0]), "%pS", r->access[0].fn);
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scnprintf(tmp[1], sizeof(tmp[1]), "%pS", r->access[1].fn);
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cmp = strcmp(tmp[0], tmp[1]);
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cur += scnprintf(cur, end - cur, "%ps / %ps",
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cmp < 0 ? r->access[0].fn : r->access[1].fn,
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cmp < 0 ? r->access[1].fn : r->access[0].fn);
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} else {
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scnprintf(cur, end - cur, "%pS", r->access[0].fn);
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/* The exact offset won't match, remove it. */
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cur = strchr(expect[0], '+');
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if (cur)
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*cur = '\0';
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}
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/* Access 1 */
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cur = expect[1];
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end = &expect[1][sizeof(expect[1]) - 1];
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if (!r->access[1].fn)
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cur += scnprintf(cur, end - cur, "race at unknown origin, with ");
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/* Access 1 & 2 */
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for (i = 0; i < 2; ++i) {
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const int ty = r->access[i].type;
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const char *const access_type =
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(ty & KCSAN_ACCESS_ASSERT) ?
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((ty & KCSAN_ACCESS_WRITE) ?
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"assert no accesses" :
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"assert no writes") :
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((ty & KCSAN_ACCESS_WRITE) ?
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((ty & KCSAN_ACCESS_COMPOUND) ?
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"read-write" :
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"write") :
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"read");
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const bool is_atomic = (ty & KCSAN_ACCESS_ATOMIC);
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const bool is_scoped = (ty & KCSAN_ACCESS_SCOPED);
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const char *const access_type_aux =
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(is_atomic && is_scoped) ? " (marked, reordered)"
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: (is_atomic ? " (marked)"
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: (is_scoped ? " (reordered)" : ""));
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if (i == 1) {
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/* Access 2 */
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cur = expect[2];
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end = &expect[2][sizeof(expect[2]) - 1];
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if (!r->access[1].fn) {
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/* Dummy string if no second access is available. */
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strcpy(cur, "<none>");
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break;
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}
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}
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cur += scnprintf(cur, end - cur, "%s%s to ", access_type,
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access_type_aux);
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if (r->access[i].addr) /* Address is optional. */
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cur += scnprintf(cur, end - cur, "0x%px of %zu bytes",
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r->access[i].addr, r->access[i].size);
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}
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spin_lock_irqsave(&observed.lock, flags);
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if (!report_available())
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goto out; /* A new report is being captured. */
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/* Finally match expected output to what we actually observed. */
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ret = strstr(observed.lines[0], expect[0]) &&
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/* Access info may appear in any order. */
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((strstr(observed.lines[1], expect[1]) &&
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strstr(observed.lines[2], expect[2])) ||
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(strstr(observed.lines[1], expect[2]) &&
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strstr(observed.lines[2], expect[1])));
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out:
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spin_unlock_irqrestore(&observed.lock, flags);
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kfree(expect);
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return ret;
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}
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static __always_inline const struct expect_report *
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__report_set_scoped(struct expect_report *r, int accesses)
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{
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BUILD_BUG_ON(accesses > 3);
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if (accesses & 1)
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r->access[0].type |= KCSAN_ACCESS_SCOPED;
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else
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r->access[0].type &= ~KCSAN_ACCESS_SCOPED;
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if (accesses & 2)
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r->access[1].type |= KCSAN_ACCESS_SCOPED;
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else
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r->access[1].type &= ~KCSAN_ACCESS_SCOPED;
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return r;
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}
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__no_kcsan
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static bool report_matches_any_reordered(struct expect_report *r)
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{
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return __report_matches(__report_set_scoped(r, 0)) ||
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__report_matches(__report_set_scoped(r, 1)) ||
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__report_matches(__report_set_scoped(r, 2)) ||
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__report_matches(__report_set_scoped(r, 3));
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}
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#ifdef CONFIG_KCSAN_WEAK_MEMORY
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/* Due to reordering accesses, any access may appear as "(reordered)". */
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#define report_matches report_matches_any_reordered
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#else
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#define report_matches __report_matches
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#endif
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/* ===== Test kernels ===== */
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static long test_sink;
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static long test_var;
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/* @test_array should be large enough to fall into multiple watchpoint slots. */
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static long test_array[3 * PAGE_SIZE / sizeof(long)];
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static struct {
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long val[8];
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} test_struct;
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static DEFINE_SEQLOCK(test_seqlock);
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static DEFINE_SPINLOCK(test_spinlock);
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static DEFINE_MUTEX(test_mutex);
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/*
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* Helper to avoid compiler optimizing out reads, and to generate source values
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* for writes.
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*/
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__no_kcsan
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static noinline void sink_value(long v) { WRITE_ONCE(test_sink, v); }
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/*
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* Generates a delay and some accesses that enter the runtime but do not produce
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* data races.
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*/
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static noinline void test_delay(int iter)
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{
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while (iter--)
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sink_value(READ_ONCE(test_sink));
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}
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static noinline void test_kernel_read(void) { sink_value(test_var); }
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static noinline void test_kernel_write(void)
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{
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test_var = READ_ONCE_NOCHECK(test_sink) + 1;
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}
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static noinline void test_kernel_write_nochange(void) { test_var = 42; }
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/* Suffixed by value-change exception filter. */
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static noinline void test_kernel_write_nochange_rcu(void) { test_var = 42; }
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static noinline void test_kernel_read_atomic(void)
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{
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sink_value(READ_ONCE(test_var));
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}
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static noinline void test_kernel_write_atomic(void)
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{
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WRITE_ONCE(test_var, READ_ONCE_NOCHECK(test_sink) + 1);
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}
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static noinline void test_kernel_atomic_rmw(void)
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{
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/* Use builtin, so we can set up the "bad" atomic/non-atomic scenario. */
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__atomic_fetch_add(&test_var, 1, __ATOMIC_RELAXED);
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}
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__no_kcsan
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static noinline void test_kernel_write_uninstrumented(void) { test_var++; }
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static noinline void test_kernel_data_race(void) { data_race(test_var++); }
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static noinline void test_kernel_assert_writer(void)
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{
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ASSERT_EXCLUSIVE_WRITER(test_var);
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}
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|
|
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static noinline void test_kernel_assert_access(void)
|
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{
|
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ASSERT_EXCLUSIVE_ACCESS(test_var);
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}
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|
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#define TEST_CHANGE_BITS 0xff00ff00
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static noinline void test_kernel_change_bits(void)
|
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{
|
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if (IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) {
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/*
|
|
* Avoid race of unknown origin for this test, just pretend they
|
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* are atomic.
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|
*/
|
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kcsan_nestable_atomic_begin();
|
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test_var ^= TEST_CHANGE_BITS;
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kcsan_nestable_atomic_end();
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} else
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WRITE_ONCE(test_var, READ_ONCE(test_var) ^ TEST_CHANGE_BITS);
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}
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|
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static noinline void test_kernel_assert_bits_change(void)
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{
|
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ASSERT_EXCLUSIVE_BITS(test_var, TEST_CHANGE_BITS);
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}
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|
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static noinline void test_kernel_assert_bits_nochange(void)
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{
|
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ASSERT_EXCLUSIVE_BITS(test_var, ~TEST_CHANGE_BITS);
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}
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|
|
|
/*
|
|
* Scoped assertions do trigger anywhere in scope. However, the report should
|
|
* still only point at the start of the scope.
|
|
*/
|
|
static noinline void test_enter_scope(void)
|
|
{
|
|
int x = 0;
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|
|
|
/* Unrelated accesses to scoped assert. */
|
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READ_ONCE(test_sink);
|
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kcsan_check_read(&x, sizeof(x));
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}
|
|
|
|
static noinline void test_kernel_assert_writer_scoped(void)
|
|
{
|
|
ASSERT_EXCLUSIVE_WRITER_SCOPED(test_var);
|
|
test_enter_scope();
|
|
}
|
|
|
|
static noinline void test_kernel_assert_access_scoped(void)
|
|
{
|
|
ASSERT_EXCLUSIVE_ACCESS_SCOPED(test_var);
|
|
test_enter_scope();
|
|
}
|
|
|
|
static noinline void test_kernel_rmw_array(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(test_array); ++i)
|
|
test_array[i]++;
|
|
}
|
|
|
|
static noinline void test_kernel_write_struct(void)
|
|
{
|
|
kcsan_check_write(&test_struct, sizeof(test_struct));
|
|
kcsan_disable_current();
|
|
test_struct.val[3]++; /* induce value change */
|
|
kcsan_enable_current();
|
|
}
|
|
|
|
static noinline void test_kernel_write_struct_part(void)
|
|
{
|
|
test_struct.val[3] = 42;
|
|
}
|
|
|
|
static noinline void test_kernel_read_struct_zero_size(void)
|
|
{
|
|
kcsan_check_read(&test_struct.val[3], 0);
|
|
}
|
|
|
|
static noinline void test_kernel_jiffies_reader(void)
|
|
{
|
|
sink_value((long)jiffies);
|
|
}
|
|
|
|
static noinline void test_kernel_seqlock_reader(void)
|
|
{
|
|
unsigned int seq;
|
|
|
|
do {
|
|
seq = read_seqbegin(&test_seqlock);
|
|
sink_value(test_var);
|
|
} while (read_seqretry(&test_seqlock, seq));
|
|
}
|
|
|
|
static noinline void test_kernel_seqlock_writer(void)
|
|
{
|
|
unsigned long flags;
|
|
|
|
write_seqlock_irqsave(&test_seqlock, flags);
|
|
test_var++;
|
|
write_sequnlock_irqrestore(&test_seqlock, flags);
|
|
}
|
|
|
|
static noinline void test_kernel_atomic_builtins(void)
|
|
{
|
|
/*
|
|
* Generate concurrent accesses, expecting no reports, ensuring KCSAN
|
|
* treats builtin atomics as actually atomic.
|
|
*/
|
|
__atomic_load_n(&test_var, __ATOMIC_RELAXED);
|
|
}
|
|
|
|
static noinline void test_kernel_xor_1bit(void)
|
|
{
|
|
/* Do not report data races between the read-writes. */
|
|
kcsan_nestable_atomic_begin();
|
|
test_var ^= 0x10000;
|
|
kcsan_nestable_atomic_end();
|
|
}
|
|
|
|
#define TEST_KERNEL_LOCKED(name, acquire, release) \
|
|
static noinline void test_kernel_##name(void) \
|
|
{ \
|
|
long *flag = &test_struct.val[0]; \
|
|
long v = 0; \
|
|
if (!(acquire)) \
|
|
return; \
|
|
while (v++ < 100) { \
|
|
test_var++; \
|
|
barrier(); \
|
|
} \
|
|
release; \
|
|
test_delay(10); \
|
|
}
|
|
|
|
TEST_KERNEL_LOCKED(with_memorder,
|
|
cmpxchg_acquire(flag, 0, 1) == 0,
|
|
smp_store_release(flag, 0));
|
|
TEST_KERNEL_LOCKED(wrong_memorder,
|
|
cmpxchg_relaxed(flag, 0, 1) == 0,
|
|
WRITE_ONCE(*flag, 0));
|
|
TEST_KERNEL_LOCKED(atomic_builtin_with_memorder,
|
|
__atomic_compare_exchange_n(flag, &v, 1, 0, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED),
|
|
__atomic_store_n(flag, 0, __ATOMIC_RELEASE));
|
|
TEST_KERNEL_LOCKED(atomic_builtin_wrong_memorder,
|
|
__atomic_compare_exchange_n(flag, &v, 1, 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED),
|
|
__atomic_store_n(flag, 0, __ATOMIC_RELAXED));
|
|
|
|
/* ===== Test cases ===== */
|
|
|
|
/*
|
|
* Tests that various barriers have the expected effect on internal state. Not
|
|
* exhaustive on atomic_t operations. Unlike the selftest, also checks for
|
|
* too-strict barrier instrumentation; these can be tolerated, because it does
|
|
* not cause false positives, but at least we should be aware of such cases.
|
|
*/
|
|
static void test_barrier_nothreads(struct kunit *test)
|
|
{
|
|
#ifdef CONFIG_KCSAN_WEAK_MEMORY
|
|
struct kcsan_scoped_access *reorder_access = ¤t->kcsan_ctx.reorder_access;
|
|
#else
|
|
struct kcsan_scoped_access *reorder_access = NULL;
|
|
#endif
|
|
arch_spinlock_t arch_spinlock = __ARCH_SPIN_LOCK_UNLOCKED;
|
|
atomic_t dummy;
|
|
|
|
KCSAN_TEST_REQUIRES(test, reorder_access != NULL);
|
|
KCSAN_TEST_REQUIRES(test, IS_ENABLED(CONFIG_SMP));
|
|
|
|
#define __KCSAN_EXPECT_BARRIER(access_type, barrier, order_before, name) \
|
|
do { \
|
|
reorder_access->type = (access_type) | KCSAN_ACCESS_SCOPED; \
|
|
reorder_access->size = sizeof(test_var); \
|
|
barrier; \
|
|
KUNIT_EXPECT_EQ_MSG(test, reorder_access->size, \
|
|
order_before ? 0 : sizeof(test_var), \
|
|
"improperly instrumented type=(" #access_type "): " name); \
|
|
} while (0)
|
|
#define KCSAN_EXPECT_READ_BARRIER(b, o) __KCSAN_EXPECT_BARRIER(0, b, o, #b)
|
|
#define KCSAN_EXPECT_WRITE_BARRIER(b, o) __KCSAN_EXPECT_BARRIER(KCSAN_ACCESS_WRITE, b, o, #b)
|
|
#define KCSAN_EXPECT_RW_BARRIER(b, o) __KCSAN_EXPECT_BARRIER(KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE, b, o, #b)
|
|
|
|
/*
|
|
* Lockdep initialization can strengthen certain locking operations due
|
|
* to calling into instrumented files; "warm up" our locks.
|
|
*/
|
|
spin_lock(&test_spinlock);
|
|
spin_unlock(&test_spinlock);
|
|
mutex_lock(&test_mutex);
|
|
mutex_unlock(&test_mutex);
|
|
|
|
/* Force creating a valid entry in reorder_access first. */
|
|
test_var = 0;
|
|
while (test_var++ < 1000000 && reorder_access->size != sizeof(test_var))
|
|
__kcsan_check_read(&test_var, sizeof(test_var));
|
|
KUNIT_ASSERT_EQ(test, reorder_access->size, sizeof(test_var));
|
|
|
|
kcsan_nestable_atomic_begin(); /* No watchpoints in called functions. */
|
|
|
|
KCSAN_EXPECT_READ_BARRIER(mb(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(wmb(), false);
|
|
KCSAN_EXPECT_READ_BARRIER(rmb(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_mb(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_wmb(), false);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_rmb(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(dma_wmb(), false);
|
|
KCSAN_EXPECT_READ_BARRIER(dma_rmb(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_mb__before_atomic(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_mb__after_atomic(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_mb__after_spinlock(), true);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_store_mb(test_var, 0), true);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_load_acquire(&test_var), false);
|
|
KCSAN_EXPECT_READ_BARRIER(smp_store_release(&test_var, 0), true);
|
|
KCSAN_EXPECT_READ_BARRIER(xchg(&test_var, 0), true);
|
|
KCSAN_EXPECT_READ_BARRIER(xchg_release(&test_var, 0), true);
|
|
KCSAN_EXPECT_READ_BARRIER(xchg_relaxed(&test_var, 0), false);
|
|
KCSAN_EXPECT_READ_BARRIER(cmpxchg(&test_var, 0, 0), true);
|
|
KCSAN_EXPECT_READ_BARRIER(cmpxchg_release(&test_var, 0, 0), true);
|
|
KCSAN_EXPECT_READ_BARRIER(cmpxchg_relaxed(&test_var, 0, 0), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_read(&dummy), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_read_acquire(&dummy), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_set(&dummy, 0), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_set_release(&dummy, 0), true);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_add(1, &dummy), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_add_return(1, &dummy), true);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_add_return_acquire(1, &dummy), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_add_return_release(1, &dummy), true);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_add_return_relaxed(1, &dummy), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_fetch_add(1, &dummy), true);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_fetch_add_acquire(1, &dummy), false);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_fetch_add_release(1, &dummy), true);
|
|
KCSAN_EXPECT_READ_BARRIER(atomic_fetch_add_relaxed(1, &dummy), false);
|
|
KCSAN_EXPECT_READ_BARRIER(test_and_set_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_READ_BARRIER(test_and_clear_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_READ_BARRIER(test_and_change_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_READ_BARRIER(clear_bit_unlock(0, &test_var), true);
|
|
KCSAN_EXPECT_READ_BARRIER(__clear_bit_unlock(0, &test_var), true);
|
|
KCSAN_EXPECT_READ_BARRIER(arch_spin_lock(&arch_spinlock), false);
|
|
KCSAN_EXPECT_READ_BARRIER(arch_spin_unlock(&arch_spinlock), true);
|
|
KCSAN_EXPECT_READ_BARRIER(spin_lock(&test_spinlock), false);
|
|
KCSAN_EXPECT_READ_BARRIER(spin_unlock(&test_spinlock), true);
|
|
KCSAN_EXPECT_READ_BARRIER(mutex_lock(&test_mutex), false);
|
|
KCSAN_EXPECT_READ_BARRIER(mutex_unlock(&test_mutex), true);
|
|
|
|
KCSAN_EXPECT_WRITE_BARRIER(mb(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(wmb(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(rmb(), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_mb(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_wmb(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_rmb(), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(dma_wmb(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(dma_rmb(), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_mb__before_atomic(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_mb__after_atomic(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_mb__after_spinlock(), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_store_mb(test_var, 0), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_load_acquire(&test_var), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(smp_store_release(&test_var, 0), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(xchg(&test_var, 0), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(xchg_release(&test_var, 0), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(xchg_relaxed(&test_var, 0), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(cmpxchg(&test_var, 0, 0), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(cmpxchg_release(&test_var, 0, 0), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(cmpxchg_relaxed(&test_var, 0, 0), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_read(&dummy), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_read_acquire(&dummy), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_set(&dummy, 0), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_set_release(&dummy, 0), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_add(1, &dummy), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_add_return(1, &dummy), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_add_return_acquire(1, &dummy), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_add_return_release(1, &dummy), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_add_return_relaxed(1, &dummy), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_fetch_add(1, &dummy), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_fetch_add_acquire(1, &dummy), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_fetch_add_release(1, &dummy), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(atomic_fetch_add_relaxed(1, &dummy), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(test_and_set_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(test_and_clear_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(test_and_change_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(clear_bit_unlock(0, &test_var), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(__clear_bit_unlock(0, &test_var), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(arch_spin_lock(&arch_spinlock), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(arch_spin_unlock(&arch_spinlock), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(spin_lock(&test_spinlock), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(spin_unlock(&test_spinlock), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(mutex_lock(&test_mutex), false);
|
|
KCSAN_EXPECT_WRITE_BARRIER(mutex_unlock(&test_mutex), true);
|
|
|
|
KCSAN_EXPECT_RW_BARRIER(mb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(wmb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(rmb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_mb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_wmb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_rmb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(dma_wmb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(dma_rmb(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_mb__before_atomic(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_mb__after_atomic(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_mb__after_spinlock(), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_store_mb(test_var, 0), true);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_load_acquire(&test_var), false);
|
|
KCSAN_EXPECT_RW_BARRIER(smp_store_release(&test_var, 0), true);
|
|
KCSAN_EXPECT_RW_BARRIER(xchg(&test_var, 0), true);
|
|
KCSAN_EXPECT_RW_BARRIER(xchg_release(&test_var, 0), true);
|
|
KCSAN_EXPECT_RW_BARRIER(xchg_relaxed(&test_var, 0), false);
|
|
KCSAN_EXPECT_RW_BARRIER(cmpxchg(&test_var, 0, 0), true);
|
|
KCSAN_EXPECT_RW_BARRIER(cmpxchg_release(&test_var, 0, 0), true);
|
|
KCSAN_EXPECT_RW_BARRIER(cmpxchg_relaxed(&test_var, 0, 0), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_read(&dummy), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_read_acquire(&dummy), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_set(&dummy, 0), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_set_release(&dummy, 0), true);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_add(1, &dummy), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_add_return(1, &dummy), true);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_add_return_acquire(1, &dummy), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_add_return_release(1, &dummy), true);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_add_return_relaxed(1, &dummy), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_fetch_add(1, &dummy), true);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_fetch_add_acquire(1, &dummy), false);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_fetch_add_release(1, &dummy), true);
|
|
KCSAN_EXPECT_RW_BARRIER(atomic_fetch_add_relaxed(1, &dummy), false);
|
|
KCSAN_EXPECT_RW_BARRIER(test_and_set_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_RW_BARRIER(test_and_clear_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_RW_BARRIER(test_and_change_bit(0, &test_var), true);
|
|
KCSAN_EXPECT_RW_BARRIER(clear_bit_unlock(0, &test_var), true);
|
|
KCSAN_EXPECT_RW_BARRIER(__clear_bit_unlock(0, &test_var), true);
|
|
KCSAN_EXPECT_RW_BARRIER(arch_spin_lock(&arch_spinlock), false);
|
|
KCSAN_EXPECT_RW_BARRIER(arch_spin_unlock(&arch_spinlock), true);
|
|
KCSAN_EXPECT_RW_BARRIER(spin_lock(&test_spinlock), false);
|
|
KCSAN_EXPECT_RW_BARRIER(spin_unlock(&test_spinlock), true);
|
|
KCSAN_EXPECT_RW_BARRIER(mutex_lock(&test_mutex), false);
|
|
KCSAN_EXPECT_RW_BARRIER(mutex_unlock(&test_mutex), true);
|
|
|
|
#ifdef clear_bit_unlock_is_negative_byte
|
|
KCSAN_EXPECT_READ_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var), true);
|
|
KCSAN_EXPECT_WRITE_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var), true);
|
|
KCSAN_EXPECT_RW_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var), true);
|
|
#endif
|
|
kcsan_nestable_atomic_end();
|
|
}
|
|
|
|
/* Simple test with normal data race. */
|
|
__no_kcsan
|
|
static void test_basic(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_write, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
},
|
|
};
|
|
struct expect_report never = {
|
|
.access = {
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_write, test_kernel_read);
|
|
do {
|
|
match_expect |= report_matches(&expect);
|
|
match_never = report_matches(&never);
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
/*
|
|
* Stress KCSAN with lots of concurrent races on different addresses until
|
|
* timeout.
|
|
*/
|
|
__no_kcsan
|
|
static void test_concurrent_races(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
/* NULL will match any address. */
|
|
{ test_kernel_rmw_array, NULL, 0, __KCSAN_ACCESS_RW(KCSAN_ACCESS_WRITE) },
|
|
{ test_kernel_rmw_array, NULL, 0, __KCSAN_ACCESS_RW(0) },
|
|
},
|
|
};
|
|
struct expect_report never = {
|
|
.access = {
|
|
{ test_kernel_rmw_array, NULL, 0, 0 },
|
|
{ test_kernel_rmw_array, NULL, 0, 0 },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_rmw_array, test_kernel_rmw_array);
|
|
do {
|
|
match_expect |= report_matches(&expect);
|
|
match_never |= report_matches(&never);
|
|
} while (!end_test_checks(false));
|
|
KUNIT_EXPECT_TRUE(test, match_expect); /* Sanity check matches exist. */
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
/* Test the KCSAN_REPORT_VALUE_CHANGE_ONLY option. */
|
|
__no_kcsan
|
|
static void test_novalue_change(struct kunit *test)
|
|
{
|
|
struct expect_report expect_rw = {
|
|
.access = {
|
|
{ test_kernel_write_nochange, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
},
|
|
};
|
|
struct expect_report expect_ww = {
|
|
.access = {
|
|
{ test_kernel_write_nochange, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_write_nochange, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
test_kernel_write_nochange(); /* Reset value. */
|
|
begin_test_checks(test_kernel_write_nochange, test_kernel_read);
|
|
do {
|
|
match_expect = report_matches(&expect_rw) || report_matches(&expect_ww);
|
|
} while (!end_test_checks(match_expect));
|
|
if (IS_ENABLED(CONFIG_KCSAN_REPORT_VALUE_CHANGE_ONLY))
|
|
KUNIT_EXPECT_FALSE(test, match_expect);
|
|
else
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
/*
|
|
* Test that the rules where the KCSAN_REPORT_VALUE_CHANGE_ONLY option should
|
|
* never apply work.
|
|
*/
|
|
__no_kcsan
|
|
static void test_novalue_change_exception(struct kunit *test)
|
|
{
|
|
struct expect_report expect_rw = {
|
|
.access = {
|
|
{ test_kernel_write_nochange_rcu, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
},
|
|
};
|
|
struct expect_report expect_ww = {
|
|
.access = {
|
|
{ test_kernel_write_nochange_rcu, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_write_nochange_rcu, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
test_kernel_write_nochange_rcu(); /* Reset value. */
|
|
begin_test_checks(test_kernel_write_nochange_rcu, test_kernel_read);
|
|
do {
|
|
match_expect = report_matches(&expect_rw) || report_matches(&expect_ww);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
/* Test that data races of unknown origin are reported. */
|
|
__no_kcsan
|
|
static void test_unknown_origin(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
{ NULL },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
begin_test_checks(test_kernel_write_uninstrumented, test_kernel_read);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
if (IS_ENABLED(CONFIG_KCSAN_REPORT_RACE_UNKNOWN_ORIGIN))
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
else
|
|
KUNIT_EXPECT_FALSE(test, match_expect);
|
|
}
|
|
|
|
/* Test KCSAN_ASSUME_PLAIN_WRITES_ATOMIC if it is selected. */
|
|
__no_kcsan
|
|
static void test_write_write_assume_atomic(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_write, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_write, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
begin_test_checks(test_kernel_write, test_kernel_write);
|
|
do {
|
|
sink_value(READ_ONCE(test_var)); /* induce value-change */
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
if (IS_ENABLED(CONFIG_KCSAN_ASSUME_PLAIN_WRITES_ATOMIC))
|
|
KUNIT_EXPECT_FALSE(test, match_expect);
|
|
else
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
/*
|
|
* Test that data races with writes larger than word-size are always reported,
|
|
* even if KCSAN_ASSUME_PLAIN_WRITES_ATOMIC is selected.
|
|
*/
|
|
__no_kcsan
|
|
static void test_write_write_struct(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_write_struct, &test_struct, sizeof(test_struct), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_write_struct, &test_struct, sizeof(test_struct), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
begin_test_checks(test_kernel_write_struct, test_kernel_write_struct);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
/*
|
|
* Test that data races where only one write is larger than word-size are always
|
|
* reported, even if KCSAN_ASSUME_PLAIN_WRITES_ATOMIC is selected.
|
|
*/
|
|
__no_kcsan
|
|
static void test_write_write_struct_part(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_write_struct, &test_struct, sizeof(test_struct), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_write_struct_part, &test_struct.val[3], sizeof(test_struct.val[3]), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
begin_test_checks(test_kernel_write_struct, test_kernel_write_struct_part);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
/* Test that races with atomic accesses never result in reports. */
|
|
__no_kcsan
|
|
static void test_read_atomic_write_atomic(struct kunit *test)
|
|
{
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_read_atomic, test_kernel_write_atomic);
|
|
do {
|
|
match_never = report_available();
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
/* Test that a race with an atomic and plain access result in reports. */
|
|
__no_kcsan
|
|
static void test_read_plain_atomic_write(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
{ test_kernel_write_atomic, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
KCSAN_TEST_REQUIRES(test, !IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS));
|
|
|
|
begin_test_checks(test_kernel_read, test_kernel_write_atomic);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
/* Test that atomic RMWs generate correct report. */
|
|
__no_kcsan
|
|
static void test_read_plain_atomic_rmw(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
{ test_kernel_atomic_rmw, &test_var, sizeof(test_var),
|
|
KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
KCSAN_TEST_REQUIRES(test, !IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS));
|
|
|
|
begin_test_checks(test_kernel_read, test_kernel_atomic_rmw);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
/* Zero-sized accesses should never cause data race reports. */
|
|
__no_kcsan
|
|
static void test_zero_size_access(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_write_struct, &test_struct, sizeof(test_struct), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_write_struct, &test_struct, sizeof(test_struct), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
struct expect_report never = {
|
|
.access = {
|
|
{ test_kernel_write_struct, &test_struct, sizeof(test_struct), KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_read_struct_zero_size, &test_struct.val[3], 0, 0 },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_write_struct, test_kernel_read_struct_zero_size);
|
|
do {
|
|
match_expect |= report_matches(&expect);
|
|
match_never = report_matches(&never);
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_TRUE(test, match_expect); /* Sanity check. */
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
/* Test the data_race() macro. */
|
|
__no_kcsan
|
|
static void test_data_race(struct kunit *test)
|
|
{
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_data_race, test_kernel_data_race);
|
|
do {
|
|
match_never = report_available();
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_assert_exclusive_writer(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_assert_writer, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT },
|
|
{ test_kernel_write_nochange, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
begin_test_checks(test_kernel_assert_writer, test_kernel_write_nochange);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_assert_exclusive_access(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_assert_access, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
begin_test_checks(test_kernel_assert_access, test_kernel_read);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_assert_exclusive_access_writer(struct kunit *test)
|
|
{
|
|
struct expect_report expect_access_writer = {
|
|
.access = {
|
|
{ test_kernel_assert_access, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_assert_writer, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT },
|
|
},
|
|
};
|
|
struct expect_report expect_access_access = {
|
|
.access = {
|
|
{ test_kernel_assert_access, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_WRITE },
|
|
{ test_kernel_assert_access, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
struct expect_report never = {
|
|
.access = {
|
|
{ test_kernel_assert_writer, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT },
|
|
{ test_kernel_assert_writer, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT },
|
|
},
|
|
};
|
|
bool match_expect_access_writer = false;
|
|
bool match_expect_access_access = false;
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_assert_access, test_kernel_assert_writer);
|
|
do {
|
|
match_expect_access_writer |= report_matches(&expect_access_writer);
|
|
match_expect_access_access |= report_matches(&expect_access_access);
|
|
match_never |= report_matches(&never);
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_TRUE(test, match_expect_access_writer);
|
|
KUNIT_EXPECT_TRUE(test, match_expect_access_access);
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_assert_exclusive_bits_change(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_assert_bits_change, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT },
|
|
{ test_kernel_change_bits, &test_var, sizeof(test_var),
|
|
KCSAN_ACCESS_WRITE | (IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS) ? 0 : KCSAN_ACCESS_ATOMIC) },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
begin_test_checks(test_kernel_assert_bits_change, test_kernel_change_bits);
|
|
do {
|
|
match_expect = report_matches(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_assert_exclusive_bits_nochange(struct kunit *test)
|
|
{
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_assert_bits_nochange, test_kernel_change_bits);
|
|
do {
|
|
match_never = report_available();
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_assert_exclusive_writer_scoped(struct kunit *test)
|
|
{
|
|
struct expect_report expect_start = {
|
|
.access = {
|
|
{ test_kernel_assert_writer_scoped, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_SCOPED },
|
|
{ test_kernel_write_nochange, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
struct expect_report expect_inscope = {
|
|
.access = {
|
|
{ test_enter_scope, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_SCOPED },
|
|
{ test_kernel_write_nochange, &test_var, sizeof(test_var), KCSAN_ACCESS_WRITE },
|
|
},
|
|
};
|
|
bool match_expect_start = false;
|
|
bool match_expect_inscope = false;
|
|
|
|
begin_test_checks(test_kernel_assert_writer_scoped, test_kernel_write_nochange);
|
|
do {
|
|
match_expect_start |= report_matches(&expect_start);
|
|
match_expect_inscope |= report_matches(&expect_inscope);
|
|
} while (!end_test_checks(match_expect_inscope));
|
|
KUNIT_EXPECT_TRUE(test, match_expect_start);
|
|
KUNIT_EXPECT_FALSE(test, match_expect_inscope);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_assert_exclusive_access_scoped(struct kunit *test)
|
|
{
|
|
struct expect_report expect_start1 = {
|
|
.access = {
|
|
{ test_kernel_assert_access_scoped, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_WRITE | KCSAN_ACCESS_SCOPED },
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
},
|
|
};
|
|
struct expect_report expect_start2 = {
|
|
.access = { expect_start1.access[0], expect_start1.access[0] },
|
|
};
|
|
struct expect_report expect_inscope = {
|
|
.access = {
|
|
{ test_enter_scope, &test_var, sizeof(test_var), KCSAN_ACCESS_ASSERT | KCSAN_ACCESS_WRITE | KCSAN_ACCESS_SCOPED },
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
},
|
|
};
|
|
bool match_expect_start = false;
|
|
bool match_expect_inscope = false;
|
|
|
|
begin_test_checks(test_kernel_assert_access_scoped, test_kernel_read);
|
|
end_time += msecs_to_jiffies(1000); /* This test requires a bit more time. */
|
|
do {
|
|
match_expect_start |= report_matches(&expect_start1) || report_matches(&expect_start2);
|
|
match_expect_inscope |= report_matches(&expect_inscope);
|
|
} while (!end_test_checks(match_expect_inscope));
|
|
KUNIT_EXPECT_TRUE(test, match_expect_start);
|
|
KUNIT_EXPECT_FALSE(test, match_expect_inscope);
|
|
}
|
|
|
|
/*
|
|
* jiffies is special (declared to be volatile) and its accesses are typically
|
|
* not marked; this test ensures that the compiler nor KCSAN gets confused about
|
|
* jiffies's declaration on different architectures.
|
|
*/
|
|
__no_kcsan
|
|
static void test_jiffies_noreport(struct kunit *test)
|
|
{
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_jiffies_reader, test_kernel_jiffies_reader);
|
|
do {
|
|
match_never = report_available();
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
/* Test that racing accesses in seqlock critical sections are not reported. */
|
|
__no_kcsan
|
|
static void test_seqlock_noreport(struct kunit *test)
|
|
{
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_seqlock_reader, test_kernel_seqlock_writer);
|
|
do {
|
|
match_never = report_available();
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
/*
|
|
* Test atomic builtins work and required instrumentation functions exist. We
|
|
* also test that KCSAN understands they're atomic by racing with them via
|
|
* test_kernel_atomic_builtins(), and expect no reports.
|
|
*
|
|
* The atomic builtins _SHOULD NOT_ be used in normal kernel code!
|
|
*/
|
|
static void test_atomic_builtins(struct kunit *test)
|
|
{
|
|
bool match_never = false;
|
|
|
|
begin_test_checks(test_kernel_atomic_builtins, test_kernel_atomic_builtins);
|
|
do {
|
|
long tmp;
|
|
|
|
kcsan_enable_current();
|
|
|
|
__atomic_store_n(&test_var, 42L, __ATOMIC_RELAXED);
|
|
KUNIT_EXPECT_EQ(test, 42L, __atomic_load_n(&test_var, __ATOMIC_RELAXED));
|
|
|
|
KUNIT_EXPECT_EQ(test, 42L, __atomic_exchange_n(&test_var, 20, __ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, 20L, test_var);
|
|
|
|
tmp = 20L;
|
|
KUNIT_EXPECT_TRUE(test, __atomic_compare_exchange_n(&test_var, &tmp, 30L,
|
|
0, __ATOMIC_RELAXED,
|
|
__ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, tmp, 20L);
|
|
KUNIT_EXPECT_EQ(test, test_var, 30L);
|
|
KUNIT_EXPECT_FALSE(test, __atomic_compare_exchange_n(&test_var, &tmp, 40L,
|
|
1, __ATOMIC_RELAXED,
|
|
__ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, tmp, 30L);
|
|
KUNIT_EXPECT_EQ(test, test_var, 30L);
|
|
|
|
KUNIT_EXPECT_EQ(test, 30L, __atomic_fetch_add(&test_var, 1, __ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, 31L, __atomic_fetch_sub(&test_var, 1, __ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, 30L, __atomic_fetch_and(&test_var, 0xf, __ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, 14L, __atomic_fetch_xor(&test_var, 0xf, __ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, 1L, __atomic_fetch_or(&test_var, 0xf0, __ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, 241L, __atomic_fetch_nand(&test_var, 0xf, __ATOMIC_RELAXED));
|
|
KUNIT_EXPECT_EQ(test, -2L, test_var);
|
|
|
|
__atomic_thread_fence(__ATOMIC_SEQ_CST);
|
|
__atomic_signal_fence(__ATOMIC_SEQ_CST);
|
|
|
|
kcsan_disable_current();
|
|
|
|
match_never = report_available();
|
|
} while (!end_test_checks(match_never));
|
|
KUNIT_EXPECT_FALSE(test, match_never);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_1bit_value_change(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_read, &test_var, sizeof(test_var), 0 },
|
|
{ test_kernel_xor_1bit, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(KCSAN_ACCESS_WRITE) },
|
|
},
|
|
};
|
|
bool match = false;
|
|
|
|
begin_test_checks(test_kernel_read, test_kernel_xor_1bit);
|
|
do {
|
|
match = IS_ENABLED(CONFIG_KCSAN_PERMISSIVE)
|
|
? report_available()
|
|
: report_matches(&expect);
|
|
} while (!end_test_checks(match));
|
|
if (IS_ENABLED(CONFIG_KCSAN_PERMISSIVE))
|
|
KUNIT_EXPECT_FALSE(test, match);
|
|
else
|
|
KUNIT_EXPECT_TRUE(test, match);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_correct_barrier(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_with_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(KCSAN_ACCESS_WRITE) },
|
|
{ test_kernel_with_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(0) },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
test_struct.val[0] = 0; /* init unlocked */
|
|
begin_test_checks(test_kernel_with_memorder, test_kernel_with_memorder);
|
|
do {
|
|
match_expect = report_matches_any_reordered(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_FALSE(test, match_expect);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_missing_barrier(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_wrong_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(KCSAN_ACCESS_WRITE) },
|
|
{ test_kernel_wrong_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(0) },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
test_struct.val[0] = 0; /* init unlocked */
|
|
begin_test_checks(test_kernel_wrong_memorder, test_kernel_wrong_memorder);
|
|
do {
|
|
match_expect = report_matches_any_reordered(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
if (IS_ENABLED(CONFIG_KCSAN_WEAK_MEMORY))
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
else
|
|
KUNIT_EXPECT_FALSE(test, match_expect);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_atomic_builtins_correct_barrier(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_atomic_builtin_with_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(KCSAN_ACCESS_WRITE) },
|
|
{ test_kernel_atomic_builtin_with_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(0) },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
test_struct.val[0] = 0; /* init unlocked */
|
|
begin_test_checks(test_kernel_atomic_builtin_with_memorder,
|
|
test_kernel_atomic_builtin_with_memorder);
|
|
do {
|
|
match_expect = report_matches_any_reordered(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
KUNIT_EXPECT_FALSE(test, match_expect);
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_atomic_builtins_missing_barrier(struct kunit *test)
|
|
{
|
|
struct expect_report expect = {
|
|
.access = {
|
|
{ test_kernel_atomic_builtin_wrong_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(KCSAN_ACCESS_WRITE) },
|
|
{ test_kernel_atomic_builtin_wrong_memorder, &test_var, sizeof(test_var), __KCSAN_ACCESS_RW(0) },
|
|
},
|
|
};
|
|
bool match_expect = false;
|
|
|
|
test_struct.val[0] = 0; /* init unlocked */
|
|
begin_test_checks(test_kernel_atomic_builtin_wrong_memorder,
|
|
test_kernel_atomic_builtin_wrong_memorder);
|
|
do {
|
|
match_expect = report_matches_any_reordered(&expect);
|
|
} while (!end_test_checks(match_expect));
|
|
if (IS_ENABLED(CONFIG_KCSAN_WEAK_MEMORY))
|
|
KUNIT_EXPECT_TRUE(test, match_expect);
|
|
else
|
|
KUNIT_EXPECT_FALSE(test, match_expect);
|
|
}
|
|
|
|
/*
|
|
* Generate thread counts for all test cases. Values generated are in interval
|
|
* [2, 5] followed by exponentially increasing thread counts from 8 to 32.
|
|
*
|
|
* The thread counts are chosen to cover potentially interesting boundaries and
|
|
* corner cases (2 to 5), and then stress the system with larger counts.
|
|
*/
|
|
static const void *nthreads_gen_params(const void *prev, char *desc)
|
|
{
|
|
long nthreads = (long)prev;
|
|
|
|
if (nthreads < 0 || nthreads >= 32)
|
|
nthreads = 0; /* stop */
|
|
else if (!nthreads)
|
|
nthreads = 2; /* initial value */
|
|
else if (nthreads < 5)
|
|
nthreads++;
|
|
else if (nthreads == 5)
|
|
nthreads = 8;
|
|
else
|
|
nthreads *= 2;
|
|
|
|
if (!preempt_model_preemptible() ||
|
|
!IS_ENABLED(CONFIG_KCSAN_INTERRUPT_WATCHER)) {
|
|
/*
|
|
* Without any preemption, keep 2 CPUs free for other tasks, one
|
|
* of which is the main test case function checking for
|
|
* completion or failure.
|
|
*/
|
|
const long min_unused_cpus = preempt_model_none() ? 2 : 0;
|
|
const long min_required_cpus = 2 + min_unused_cpus;
|
|
|
|
if (num_online_cpus() < min_required_cpus) {
|
|
pr_err_once("Too few online CPUs (%u < %ld) for test\n",
|
|
num_online_cpus(), min_required_cpus);
|
|
nthreads = 0;
|
|
} else if (nthreads >= num_online_cpus() - min_unused_cpus) {
|
|
/* Use negative value to indicate last param. */
|
|
nthreads = -(num_online_cpus() - min_unused_cpus);
|
|
pr_warn_once("Limiting number of threads to %ld (only %d online CPUs)\n",
|
|
-nthreads, num_online_cpus());
|
|
}
|
|
}
|
|
|
|
snprintf(desc, KUNIT_PARAM_DESC_SIZE, "threads=%ld", abs(nthreads));
|
|
return (void *)nthreads;
|
|
}
|
|
|
|
#define KCSAN_KUNIT_CASE(test_name) KUNIT_CASE_PARAM(test_name, nthreads_gen_params)
|
|
static struct kunit_case kcsan_test_cases[] = {
|
|
KUNIT_CASE(test_barrier_nothreads),
|
|
KCSAN_KUNIT_CASE(test_basic),
|
|
KCSAN_KUNIT_CASE(test_concurrent_races),
|
|
KCSAN_KUNIT_CASE(test_novalue_change),
|
|
KCSAN_KUNIT_CASE(test_novalue_change_exception),
|
|
KCSAN_KUNIT_CASE(test_unknown_origin),
|
|
KCSAN_KUNIT_CASE(test_write_write_assume_atomic),
|
|
KCSAN_KUNIT_CASE(test_write_write_struct),
|
|
KCSAN_KUNIT_CASE(test_write_write_struct_part),
|
|
KCSAN_KUNIT_CASE(test_read_atomic_write_atomic),
|
|
KCSAN_KUNIT_CASE(test_read_plain_atomic_write),
|
|
KCSAN_KUNIT_CASE(test_read_plain_atomic_rmw),
|
|
KCSAN_KUNIT_CASE(test_zero_size_access),
|
|
KCSAN_KUNIT_CASE(test_data_race),
|
|
KCSAN_KUNIT_CASE(test_assert_exclusive_writer),
|
|
KCSAN_KUNIT_CASE(test_assert_exclusive_access),
|
|
KCSAN_KUNIT_CASE(test_assert_exclusive_access_writer),
|
|
KCSAN_KUNIT_CASE(test_assert_exclusive_bits_change),
|
|
KCSAN_KUNIT_CASE(test_assert_exclusive_bits_nochange),
|
|
KCSAN_KUNIT_CASE(test_assert_exclusive_writer_scoped),
|
|
KCSAN_KUNIT_CASE(test_assert_exclusive_access_scoped),
|
|
KCSAN_KUNIT_CASE(test_jiffies_noreport),
|
|
KCSAN_KUNIT_CASE(test_seqlock_noreport),
|
|
KCSAN_KUNIT_CASE(test_atomic_builtins),
|
|
KCSAN_KUNIT_CASE(test_1bit_value_change),
|
|
KCSAN_KUNIT_CASE(test_correct_barrier),
|
|
KCSAN_KUNIT_CASE(test_missing_barrier),
|
|
KCSAN_KUNIT_CASE(test_atomic_builtins_correct_barrier),
|
|
KCSAN_KUNIT_CASE(test_atomic_builtins_missing_barrier),
|
|
{},
|
|
};
|
|
|
|
/* ===== End test cases ===== */
|
|
|
|
/* Concurrent accesses from interrupts. */
|
|
__no_kcsan
|
|
static void access_thread_timer(struct timer_list *timer)
|
|
{
|
|
static atomic_t cnt = ATOMIC_INIT(0);
|
|
unsigned int idx;
|
|
void (*func)(void);
|
|
|
|
idx = (unsigned int)atomic_inc_return(&cnt) % ARRAY_SIZE(access_kernels);
|
|
/* Acquire potential initialization. */
|
|
func = smp_load_acquire(&access_kernels[idx]);
|
|
if (func)
|
|
func();
|
|
}
|
|
|
|
/* The main loop for each thread. */
|
|
__no_kcsan
|
|
static int access_thread(void *arg)
|
|
{
|
|
struct timer_list timer;
|
|
unsigned int cnt = 0;
|
|
unsigned int idx;
|
|
void (*func)(void);
|
|
|
|
timer_setup_on_stack(&timer, access_thread_timer, 0);
|
|
do {
|
|
might_sleep();
|
|
|
|
if (!timer_pending(&timer))
|
|
mod_timer(&timer, jiffies + 1);
|
|
else {
|
|
/* Iterate through all kernels. */
|
|
idx = cnt++ % ARRAY_SIZE(access_kernels);
|
|
/* Acquire potential initialization. */
|
|
func = smp_load_acquire(&access_kernels[idx]);
|
|
if (func)
|
|
func();
|
|
}
|
|
} while (!torture_must_stop());
|
|
del_timer_sync(&timer);
|
|
destroy_timer_on_stack(&timer);
|
|
|
|
torture_kthread_stopping("access_thread");
|
|
return 0;
|
|
}
|
|
|
|
__no_kcsan
|
|
static int test_init(struct kunit *test)
|
|
{
|
|
unsigned long flags;
|
|
int nthreads;
|
|
int i;
|
|
|
|
spin_lock_irqsave(&observed.lock, flags);
|
|
for (i = 0; i < ARRAY_SIZE(observed.lines); ++i)
|
|
observed.lines[i][0] = '\0';
|
|
observed.nlines = 0;
|
|
spin_unlock_irqrestore(&observed.lock, flags);
|
|
|
|
if (strstr(test->name, "nothreads"))
|
|
return 0;
|
|
|
|
if (!torture_init_begin((char *)test->name, 1))
|
|
return -EBUSY;
|
|
|
|
if (WARN_ON(threads))
|
|
goto err;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(access_kernels); ++i) {
|
|
if (WARN_ON(access_kernels[i]))
|
|
goto err;
|
|
}
|
|
|
|
nthreads = abs((long)test->param_value);
|
|
if (WARN_ON(!nthreads))
|
|
goto err;
|
|
|
|
threads = kcalloc(nthreads + 1, sizeof(struct task_struct *), GFP_KERNEL);
|
|
if (WARN_ON(!threads))
|
|
goto err;
|
|
|
|
threads[nthreads] = NULL;
|
|
for (i = 0; i < nthreads; ++i) {
|
|
if (torture_create_kthread(access_thread, NULL, threads[i]))
|
|
goto err;
|
|
}
|
|
|
|
torture_init_end();
|
|
|
|
return 0;
|
|
|
|
err:
|
|
kfree(threads);
|
|
threads = NULL;
|
|
torture_init_end();
|
|
return -EINVAL;
|
|
}
|
|
|
|
__no_kcsan
|
|
static void test_exit(struct kunit *test)
|
|
{
|
|
struct task_struct **stop_thread;
|
|
int i;
|
|
|
|
if (strstr(test->name, "nothreads"))
|
|
return;
|
|
|
|
if (torture_cleanup_begin())
|
|
return;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(access_kernels); ++i)
|
|
WRITE_ONCE(access_kernels[i], NULL);
|
|
|
|
if (threads) {
|
|
for (stop_thread = threads; *stop_thread; stop_thread++)
|
|
torture_stop_kthread(reader_thread, *stop_thread);
|
|
|
|
kfree(threads);
|
|
threads = NULL;
|
|
}
|
|
|
|
torture_cleanup_end();
|
|
}
|
|
|
|
__no_kcsan
|
|
static void register_tracepoints(struct tracepoint *tp, void *ignore)
|
|
{
|
|
check_trace_callback_type_console(probe_console);
|
|
if (!strcmp(tp->name, "console"))
|
|
WARN_ON(tracepoint_probe_register(tp, probe_console, NULL));
|
|
}
|
|
|
|
__no_kcsan
|
|
static void unregister_tracepoints(struct tracepoint *tp, void *ignore)
|
|
{
|
|
if (!strcmp(tp->name, "console"))
|
|
tracepoint_probe_unregister(tp, probe_console, NULL);
|
|
}
|
|
|
|
static int kcsan_suite_init(struct kunit_suite *suite)
|
|
{
|
|
/*
|
|
* Because we want to be able to build the test as a module, we need to
|
|
* iterate through all known tracepoints, since the static registration
|
|
* won't work here.
|
|
*/
|
|
for_each_kernel_tracepoint(register_tracepoints, NULL);
|
|
return 0;
|
|
}
|
|
|
|
static void kcsan_suite_exit(struct kunit_suite *suite)
|
|
{
|
|
for_each_kernel_tracepoint(unregister_tracepoints, NULL);
|
|
tracepoint_synchronize_unregister();
|
|
}
|
|
|
|
static struct kunit_suite kcsan_test_suite = {
|
|
.name = "kcsan",
|
|
.test_cases = kcsan_test_cases,
|
|
.init = test_init,
|
|
.exit = test_exit,
|
|
.suite_init = kcsan_suite_init,
|
|
.suite_exit = kcsan_suite_exit,
|
|
};
|
|
|
|
kunit_test_suites(&kcsan_test_suite);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR("Marco Elver <elver@google.com>");
|