diff --git a/sys/sys/kassert.h b/sys/sys/kassert.h index 25e2b025a11a..ab2313bcbd8b 100644 --- a/sys/sys/kassert.h +++ b/sys/sys/kassert.h @@ -1,184 +1,190 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1999 Eivind Eklund * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef _SYS_KASSERT_H_ #define _SYS_KASSERT_H_ #include #ifdef _KERNEL extern const char *panicstr; /* panic message */ #define KERNEL_PANICKED() __predict_false(panicstr != NULL) /* * Trap accesses going through a pointer. Moreover if kasan is available trap * reading the pointer itself. * * Sample usage: you have a struct with numerous fields and by API contract * only some of them get populated, even if the implementation temporary writes * to them. You can use DEBUG_POISON_POINTER so that the consumer which should * no be looking at the field gets caught. * * DEBUG_POISON_POINTER(obj->ptr); * .... * if (obj->ptr != NULL) // traps with kasan, does not trap otherwise * .... * if (obj->ptr->field) // traps with and without kasan */ #ifdef INVARIANTS #include extern caddr_t poisoned_buf; #define DEBUG_POISON_POINTER_VALUE poisoned_buf #define DEBUG_POISON_POINTER(x) ({ \ x = (void *)(DEBUG_POISON_POINTER_VALUE); \ kasan_mark(&x, 0, sizeof(x), KASAN_GENERIC_REDZONE); \ }) #else #define DEBUG_POISON_POINTER(x) #endif #ifdef INVARIANTS /* The option is always available */ #define VNASSERT(exp, vp, msg) do { \ if (__predict_false(!(exp))) { \ vn_printf(vp, "VNASSERT failed: %s not true at %s:%d (%s)\n",\ #exp, __FILE__, __LINE__, __func__); \ kassert_panic msg; \ } \ } while (0) #define MPASSERT(exp, mp, msg) do { \ if (__predict_false(!(exp))) { \ printf("MPASSERT mp %p failed: %s not true at %s:%d (%s)\n",\ (mp), #exp, __FILE__, __LINE__, __func__); \ kassert_panic msg; \ } \ } while (0) #define VNPASS(exp, vp) do { \ const char *_exp = #exp; \ VNASSERT(exp, vp, ("condition %s not met at %s:%d (%s)", \ _exp, __FILE__, __LINE__, __func__)); \ } while (0) #define MPPASS(exp, mp) do { \ const char *_exp = #exp; \ MPASSERT(exp, mp, ("condition %s not met at %s:%d (%s)", \ _exp, __FILE__, __LINE__, __func__)); \ } while (0) #define __assert_unreachable() \ panic("executing segment marked as unreachable at %s:%d (%s)\n", \ __FILE__, __LINE__, __func__) #else /* INVARIANTS */ #define VNASSERT(exp, vp, msg) do { \ } while (0) #define MPASSERT(exp, mp, msg) do { \ } while (0) #define VNPASS(exp, vp) do { \ } while (0) #define MPPASS(exp, mp) do { \ } while (0) #define __assert_unreachable() __unreachable() #endif /* INVARIANTS */ #ifndef CTASSERT /* Allow lint to override */ #define CTASSERT(x) _Static_assert(x, "compile-time assertion failed") #endif /* * These functions need to be declared before the KASSERT macro is invoked in * !KASSERT_PANIC_OPTIONAL builds, so their declarations are sort of out of * place compared to other function definitions in this header. On the other * hand, this header is a bit disorganized anyway. */ void panic(const char *, ...) __dead2 __printflike(1, 2); void vpanic(const char *, __va_list) __dead2 __printflike(1, 0); #endif /* _KERNEL */ #if defined(_STANDALONE) /* * Until we have more experience with KASSERTS that are called * from the boot loader, they are off. The bootloader does this * a little differently than the kernel (we just call printf atm). * we avoid most of the common functions in the boot loader, so * declare printf() here too. */ int printf(const char *, ...) __printflike(1, 2); # define kassert_panic printf #else /* !_STANDALONE */ # if defined(WITNESS) || defined(INVARIANT_SUPPORT) # ifdef KASSERT_PANIC_OPTIONAL void kassert_panic(const char *fmt, ...) __printflike(1, 2); # else # define kassert_panic panic # endif /* KASSERT_PANIC_OPTIONAL */ # endif /* defined(WITNESS) || defined(INVARIANT_SUPPORT) */ #endif /* _STANDALONE */ +/* + * Kernel assertion; see KASSERT(9) for details. + */ #if (defined(_KERNEL) && defined(INVARIANTS)) || defined(_STANDALONE) #define KASSERT(exp,msg) do { \ if (__predict_false(!(exp))) \ kassert_panic msg; \ } while (0) #else /* !(KERNEL && INVARIANTS) && !_STANDALONE */ #define KASSERT(exp,msg) do { \ } while (0) #endif /* (_KERNEL && INVARIANTS) || _STANDALONE */ #ifdef _KERNEL /* - * Helpful macros for quickly coming up with assertions with informative - * panic messages. + * Macros for generating panic messages based on the exact condition text. + * + * NOTE: Use these with care, as the resulting message might omit key + * information required to understand the assertion failure. Consult the + * MPASS(9) man page for guidance. */ #define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) #define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) #define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) #define MPASS4(ex, what, file, line) \ KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) /* * Assert that a pointer can be loaded from memory atomically. * * This assertion enforces stronger alignment than necessary. For example, * on some architectures, atomicity for unaligned loads will depend on * whether or not the load spans multiple cache lines. */ #define ASSERT_ATOMIC_LOAD_PTR(var, msg) \ KASSERT(sizeof(var) == sizeof(void *) && \ ((uintptr_t)&(var) & (sizeof(void *) - 1)) == 0, msg) /* * Assert that a thread is in critical(9) section. */ #define CRITICAL_ASSERT(td) \ KASSERT((td)->td_critnest >= 1, ("Not in critical section")) #endif /* _KERNEL */ #endif /* _SYS_KASSERT_H_ */