[compiler-rt] f7164c7 - [NFC][scudo] Add reference to a QEMU bug

[Vitaly Buka via llvm-commits]

Author: Vitaly Buka
Date: 2021-04-28T14:57:53-07:00
New Revision: f7164c77144a130b830d9bb3fbe829783965fab3

URL: https://github.com/llvm/llvm-project/commit/f7164c77144a130b830d9bb3fbe829783965fab3
DIFF: https://github.com/llvm/llvm-project/commit/f7164c77144a130b830d9bb3fbe829783965fab3.diff

LOG: [NFC][scudo] Add reference to a QEMU bug

D101031 added workaround for the bug.

Added: 
    

Modified: 
    compiler-rt/lib/scudo/standalone/linux.cpp

Removed: 
    


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diff  --git a/compiler-rt/lib/scudo/standalone/linux.cpp b/compiler-rt/lib/scudo/standalone/linux.cpp
index 63a8e43b5bfb0..7ec69878c0ec7 100644
--- a/compiler-rt/lib/scudo/standalone/linux.cpp
+++ b/compiler-rt/lib/scudo/standalone/linux.cpp
@@ -122,6 +122,7 @@ void releasePagesToOS(uptr BaseAddress, uptr Offset, uptr Size,
   if (madviseNeedsMemsetCached()) {
     // Workaround for QEMU-user ignoring MADV_DONTNEED.
     // https://github.com/qemu/qemu/blob/b1cffefa1b163bce9aebc3416f562c1d3886eeaa/linux-user/syscall.c#L11941
+    // https://bugs.launchpad.net/qemu/+bug/1926521
     memset(Addr, 0, Size);
   }
   while (madvise(Addr, Size, MADV_DONTNEED) == -1 && errno == EAGAIN) {