linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Marco Elver <elver@google.com>
To: elver@google.com, "Paul E. McKenney" <paulmck@kernel.org>
Cc: Alexander Potapenko <glider@google.com>,
	Boqun Feng <boqun.feng@gmail.com>, Borislav Petkov <bp@alien8.de>,
	Dmitry Vyukov <dvyukov@google.com>,
	Ingo Molnar <mingo@kernel.org>,
	Josh Poimboeuf <jpoimboe@redhat.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Waiman Long <longman@redhat.com>, Will Deacon <will@kernel.org>,
	kasan-dev@googlegroups.com, linux-arch@vger.kernel.org,
	linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org
Subject: [PATCH v2 05/23] kcsan: Add core memory barrier instrumentation functions
Date: Thu, 18 Nov 2021 09:10:09 +0100	[thread overview]
Message-ID: <20211118081027.3175699-6-elver@google.com> (raw)
In-Reply-To: <20211118081027.3175699-1-elver@google.com>

Add the core memory barrier instrumentation functions. These invalidate
the current in-flight reordered access based on the rules for the
respective barrier types and in-flight access type.

Signed-off-by: Marco Elver <elver@google.com>
---
v2:
* Rename kcsan_atomic_release() to kcsan_atomic_builtin_memorder() to
  avoid confusion.
---
 include/linux/kcsan-checks.h | 41 ++++++++++++++++++++++++++++++++++--
 kernel/kcsan/core.c          | 36 +++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+), 2 deletions(-)

diff --git a/include/linux/kcsan-checks.h b/include/linux/kcsan-checks.h
index a1c6a89fde71..c9e7c39a7d7b 100644
--- a/include/linux/kcsan-checks.h
+++ b/include/linux/kcsan-checks.h
@@ -36,6 +36,26 @@
  */
 void __kcsan_check_access(const volatile void *ptr, size_t size, int type);
 
+/**
+ * __kcsan_mb - full memory barrier instrumentation
+ */
+void __kcsan_mb(void);
+
+/**
+ * __kcsan_wmb - write memory barrier instrumentation
+ */
+void __kcsan_wmb(void);
+
+/**
+ * __kcsan_rmb - read memory barrier instrumentation
+ */
+void __kcsan_rmb(void);
+
+/**
+ * __kcsan_release - release barrier instrumentation
+ */
+void __kcsan_release(void);
+
 /**
  * kcsan_disable_current - disable KCSAN for the current context
  *
@@ -159,6 +179,10 @@ void kcsan_end_scoped_access(struct kcsan_scoped_access *sa);
 static inline void __kcsan_check_access(const volatile void *ptr, size_t size,
 					int type) { }
 
+static inline void __kcsan_mb(void)			{ }
+static inline void __kcsan_wmb(void)			{ }
+static inline void __kcsan_rmb(void)			{ }
+static inline void __kcsan_release(void)		{ }
 static inline void kcsan_disable_current(void)		{ }
 static inline void kcsan_enable_current(void)		{ }
 static inline void kcsan_enable_current_nowarn(void)	{ }
@@ -191,12 +215,25 @@ static inline void kcsan_end_scoped_access(struct kcsan_scoped_access *sa) { }
  */
 #define __kcsan_disable_current kcsan_disable_current
 #define __kcsan_enable_current kcsan_enable_current_nowarn
-#else
+#else /* __SANITIZE_THREAD__ */
 static inline void kcsan_check_access(const volatile void *ptr, size_t size,
 				      int type) { }
 static inline void __kcsan_enable_current(void)  { }
 static inline void __kcsan_disable_current(void) { }
-#endif
+#endif /* __SANITIZE_THREAD__ */
+
+#if defined(CONFIG_KCSAN_WEAK_MEMORY) && \
+		(defined(__SANITIZE_THREAD__) || defined(__KCSAN_INSTRUMENT_BARRIERS__))
+#define kcsan_mb	__kcsan_mb
+#define kcsan_wmb	__kcsan_wmb
+#define kcsan_rmb	__kcsan_rmb
+#define kcsan_release	__kcsan_release
+#else /* CONFIG_KCSAN_WEAK_MEMORY && (__SANITIZE_THREAD__ || __KCSAN_INSTRUMENT_BARRIERS__) */
+static inline void kcsan_mb(void)		{ }
+static inline void kcsan_wmb(void)		{ }
+static inline void kcsan_rmb(void)		{ }
+static inline void kcsan_release(void)		{ }
+#endif /* CONFIG_KCSAN_WEAK_MEMORY && (__SANITIZE_THREAD__ || __KCSAN_INSTRUMENT_BARRIERS__) */
 
 /**
  * __kcsan_check_read - check regular read access for races
diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c
index 24d82baa807d..840ed8e35f75 100644
--- a/kernel/kcsan/core.c
+++ b/kernel/kcsan/core.c
@@ -955,6 +955,28 @@ void __kcsan_check_access(const volatile void *ptr, size_t size, int type)
 }
 EXPORT_SYMBOL(__kcsan_check_access);
 
+#define DEFINE_MEMORY_BARRIER(name, order_before_cond)                         \
+	kcsan_noinstr void __kcsan_##name(void)                                \
+	{                                                                      \
+		struct kcsan_scoped_access *sa;                                \
+		if (within_noinstr(_RET_IP_))                                  \
+			return;                                                \
+		instrumentation_begin();                                       \
+		sa = get_reorder_access(get_ctx());                            \
+		if (!sa)                                                       \
+			goto out;                                              \
+		if (order_before_cond)                                         \
+			sa->size = 0;                                          \
+	out:                                                                   \
+		instrumentation_end();                                         \
+	}                                                                      \
+	EXPORT_SYMBOL(__kcsan_##name)
+
+DEFINE_MEMORY_BARRIER(mb, true);
+DEFINE_MEMORY_BARRIER(wmb, sa->type & (KCSAN_ACCESS_WRITE | KCSAN_ACCESS_COMPOUND));
+DEFINE_MEMORY_BARRIER(rmb, !(sa->type & KCSAN_ACCESS_WRITE) || (sa->type & KCSAN_ACCESS_COMPOUND));
+DEFINE_MEMORY_BARRIER(release, true);
+
 /*
  * KCSAN uses the same instrumentation that is emitted by supported compilers
  * for ThreadSanitizer (TSAN).
@@ -1143,10 +1165,19 @@ EXPORT_SYMBOL(__tsan_init);
  * functions, whose job is to also execute the operation itself.
  */
 
+static __always_inline void kcsan_atomic_builtin_memorder(int memorder)
+{
+	if (memorder == __ATOMIC_RELEASE ||
+	    memorder == __ATOMIC_SEQ_CST ||
+	    memorder == __ATOMIC_ACQ_REL)
+		__kcsan_release();
+}
+
 #define DEFINE_TSAN_ATOMIC_LOAD_STORE(bits)                                                        \
 	u##bits __tsan_atomic##bits##_load(const u##bits *ptr, int memorder);                      \
 	u##bits __tsan_atomic##bits##_load(const u##bits *ptr, int memorder)                       \
 	{                                                                                          \
+		kcsan_atomic_builtin_memorder(memorder);                                           \
 		if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) {                                    \
 			check_access(ptr, bits / BITS_PER_BYTE, KCSAN_ACCESS_ATOMIC, _RET_IP_);    \
 		}                                                                                  \
@@ -1156,6 +1187,7 @@ EXPORT_SYMBOL(__tsan_init);
 	void __tsan_atomic##bits##_store(u##bits *ptr, u##bits v, int memorder);                   \
 	void __tsan_atomic##bits##_store(u##bits *ptr, u##bits v, int memorder)                    \
 	{                                                                                          \
+		kcsan_atomic_builtin_memorder(memorder);                                           \
 		if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) {                                    \
 			check_access(ptr, bits / BITS_PER_BYTE,                                    \
 				     KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ATOMIC, _RET_IP_);          \
@@ -1168,6 +1200,7 @@ EXPORT_SYMBOL(__tsan_init);
 	u##bits __tsan_atomic##bits##_##op(u##bits *ptr, u##bits v, int memorder);                 \
 	u##bits __tsan_atomic##bits##_##op(u##bits *ptr, u##bits v, int memorder)                  \
 	{                                                                                          \
+		kcsan_atomic_builtin_memorder(memorder);                                           \
 		if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) {                                    \
 			check_access(ptr, bits / BITS_PER_BYTE,                                    \
 				     KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE |                  \
@@ -1200,6 +1233,7 @@ EXPORT_SYMBOL(__tsan_init);
 	int __tsan_atomic##bits##_compare_exchange_##strength(u##bits *ptr, u##bits *exp,          \
 							      u##bits val, int mo, int fail_mo)    \
 	{                                                                                          \
+		kcsan_atomic_builtin_memorder(mo);                                                 \
 		if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) {                                    \
 			check_access(ptr, bits / BITS_PER_BYTE,                                    \
 				     KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE |                  \
@@ -1215,6 +1249,7 @@ EXPORT_SYMBOL(__tsan_init);
 	u##bits __tsan_atomic##bits##_compare_exchange_val(u##bits *ptr, u##bits exp, u##bits val, \
 							   int mo, int fail_mo)                    \
 	{                                                                                          \
+		kcsan_atomic_builtin_memorder(mo);                                                 \
 		if (!IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) {                                    \
 			check_access(ptr, bits / BITS_PER_BYTE,                                    \
 				     KCSAN_ACCESS_COMPOUND | KCSAN_ACCESS_WRITE |                  \
@@ -1246,6 +1281,7 @@ DEFINE_TSAN_ATOMIC_OPS(64);
 void __tsan_atomic_thread_fence(int memorder);
 void __tsan_atomic_thread_fence(int memorder)
 {
+	kcsan_atomic_builtin_memorder(memorder);
 	__atomic_thread_fence(memorder);
 }
 EXPORT_SYMBOL(__tsan_atomic_thread_fence);
-- 
2.34.0.rc2.393.gf8c9666880-goog


  parent reply	other threads:[~2021-11-18  8:11 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-18  8:10 [PATCH v2 00/23] kcsan: Support detecting a subset of missing memory barriers Marco Elver
2021-11-18  8:10 ` [PATCH v2 01/23] kcsan: Refactor reading of instrumented memory Marco Elver
2021-11-18 11:08   ` Mark Rutland
2021-11-18  8:10 ` [PATCH v2 02/23] kcsan: Remove redundant zero-initialization of globals Marco Elver
2021-11-18 11:09   ` Mark Rutland
2021-11-18  8:10 ` [PATCH v2 03/23] kcsan: Avoid checking scoped accesses from nested contexts Marco Elver
2021-11-29  8:47   ` Boqun Feng
2021-11-29 10:57     ` Marco Elver
2021-11-29 14:26       ` Boqun Feng
2021-11-29 14:42         ` Marco Elver
2021-11-18  8:10 ` [PATCH v2 04/23] kcsan: Add core support for a subset of weak memory modeling Marco Elver
2021-11-18  8:10 ` Marco Elver [this message]
2021-11-18  8:10 ` [PATCH v2 06/23] kcsan, kbuild: Add option for barrier instrumentation only Marco Elver
2021-11-18  8:10 ` [PATCH v2 07/23] kcsan: Call scoped accesses reordered in reports Marco Elver
2021-11-18  8:10 ` [PATCH v2 08/23] kcsan: Show location access was reordered to Marco Elver
2021-11-18  8:10 ` [PATCH v2 09/23] kcsan: Document modeling of weak memory Marco Elver
2021-11-18  8:10 ` [PATCH v2 10/23] kcsan: test: Match reordered or normal accesses Marco Elver
2021-11-18  8:10 ` [PATCH v2 11/23] kcsan: test: Add test cases for memory barrier instrumentation Marco Elver
2021-11-18  8:10 ` [PATCH v2 12/23] kcsan: Ignore GCC 11+ warnings about TSan runtime support Marco Elver
2021-11-18  8:10 ` [PATCH v2 13/23] kcsan: selftest: Add test case to check memory barrier instrumentation Marco Elver
2021-11-18  8:10 ` [PATCH v2 14/23] locking/barriers, kcsan: Add instrumentation for barriers Marco Elver
2021-11-18  8:10 ` [PATCH v2 15/23] locking/barriers, kcsan: Support generic instrumentation Marco Elver
2021-11-18  8:10 ` [PATCH v2 16/23] locking/atomics, kcsan: Add instrumentation for barriers Marco Elver
2021-11-18  8:10 ` [PATCH v2 17/23] asm-generic/bitops, " Marco Elver
2021-11-18  8:10 ` [PATCH v2 18/23] x86/barriers, kcsan: Use generic instrumentation for non-smp barriers Marco Elver
2021-11-18  8:10 ` [PATCH v2 19/23] x86/qspinlock, kcsan: Instrument barrier of pv_queued_spin_unlock() Marco Elver
2021-11-18  8:10 ` [PATCH v2 20/23] mm, kcsan: Enable barrier instrumentation Marco Elver
2021-11-18  8:10 ` [PATCH v2 21/23] sched, kcsan: Enable memory " Marco Elver
2021-11-18  8:10 ` [PATCH v2 22/23] objtool, kcsan: Add memory barrier instrumentation to whitelist Marco Elver
2021-11-18  8:10 ` [PATCH v2 23/23] objtool, kcsan: Remove memory barrier instrumentation from noinstr Marco Elver
2021-11-19 20:31   ` Josh Poimboeuf
2021-11-19 21:31     ` Marco Elver
2021-11-23 11:29     ` Marco Elver
2021-11-24 17:53       ` Josh Poimboeuf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211118081027.3175699-6-elver@google.com \
    --to=elver@google.com \
    --cc=boqun.feng@gmail.com \
    --cc=bp@alien8.de \
    --cc=dvyukov@google.com \
    --cc=glider@google.com \
    --cc=jpoimboe@redhat.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=longman@redhat.com \
    --cc=mark.rutland@arm.com \
    --cc=mingo@kernel.org \
    --cc=paulmck@kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --cc=will@kernel.org \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).