Changeset 180649 in webkit

Timestamp:

Feb 25, 2015 4:24:25 PM (9 years ago)

Author:

mark.lam@apple.com

Message:

ASan does not like JSC::MachineThreads::tryCopyOtherThreadStack.
<​https://webkit.org/b/141672>

Reviewed by Alexey Proskuryakov.

ASan does not like the fact that we memcpy the stack for GC scans. So,
we're working around this by using our own memcpy (asanUnsafeMemcpy)
implementation that we can tell ASan to ignore.

Source/JavaScriptCore:

• heap/MachineStackMarker.cpp:

(JSC::asanUnsafeMemcpy):

Tools:

Also removed the previous added directive to ignore *tryCopyOtherThreadStack*
which isn't effective for working around this issue.

• asan/webkit-asan-ignore.txt:

Location:

trunk

Files:

• Source/JavaScriptCore/ChangeLog (modified) (1 diff)
• Source/JavaScriptCore/heap/MachineStackMarker.cpp (modified) (1 diff)
• Tools/ChangeLog (modified) (1 diff)
• Tools/asan/webkit-asan-ignore.txt (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2015-02-25  Mark Lam  <mark.lam@apple.com>
+
+        ASan does not like JSC::MachineThreads::tryCopyOtherThreadStack.
+        <https://webkit.org/b/141672>
+
+        Reviewed by Alexey Proskuryakov.
+
+        ASan does not like the fact that we memcpy the stack for GC scans.  So,
+        we're working around this by using our own memcpy (asanUnsafeMemcpy)
+        implementation that we can tell ASan to ignore.
+
+        * heap/MachineStackMarker.cpp:
+        (JSC::asanUnsafeMemcpy):
+
 2015-02-25  Benjamin Poulain  <bpoulain@apple.com>
 

trunk/Source/JavaScriptCore/heap/MachineStackMarker.cpp

@@ -411 +411 @@
 }
 
+#if ASAN_ENABLED
+void asanUnsafeMemcpy(void* dst, const void* src, size_t);
+void asanUnsafeMemcpy(void* dst, const void* src, size_t size)
+{
+    size_t dstAsSize = reinterpret_cast<size_t>(dst);
+    size_t srcAsSize = reinterpret_cast<size_t>(src);
+    RELEASE_ASSERT(dstAsSize == WTF::roundUpToMultipleOf<sizeof(intptr_t)>(dstAsSize));
+    RELEASE_ASSERT(srcAsSize == WTF::roundUpToMultipleOf<sizeof(intptr_t)>(srcAsSize));
+    RELEASE_ASSERT(size == WTF::roundUpToMultipleOf<sizeof(intptr_t)>(size));
+
+    intptr_t* dstPtr = reinterpret_cast<intptr_t*>(dst);
+    const intptr_t* srcPtr = reinterpret_cast<const intptr_t*>(src);
+    size /= sizeof(intptr_t);
+    while (size--)
+        *dstPtr++ = *srcPtr++;
+}
+    
+#define memcpy asanUnsafeMemcpy
+#endif
+
 // This function must not call malloc(), free(), or any other function that might
 // acquire a lock. Since 'thread' is suspended, trying to acquire a lock

trunk/Tools/ChangeLog

@@ +1 @@
+2015-02-25  Mark Lam  <mark.lam@apple.com>
+
+        ASan does not like JSC::MachineThreads::tryCopyOtherThreadStack.
+        <https://webkit.org/b/141672>
+
+        Reviewed by Alexey Proskuryakov.
+
+        ASan does not like the fact that we memcpy the stack for GC scans.  So,
+        we're working around this by using our own memcpy (asanUnsafeMemcpy)
+        implementation that we can tell ASan to ignore.
+
+        Also removed the previous added directive to ignore *tryCopyOtherThreadStack*
+        which isn't effective for working around this issue. 
+
+        * asan/webkit-asan-ignore.txt:
+
 2015-02-25  Benjamin Poulain  <bpoulain@apple.com>
 

trunk/Tools/asan/webkit-asan-ignore.txt

@@ -5 +5 @@
 # called from prepareOSREntry(), but there is currently no way to express this in a blacklist.
 fun:*JSC*Register*jsValue*
-fun:*JSC*MachineThreads*tryCopyOtherThreadStack*
+fun:*asanUnsafeMemcpy*