From: Jianzhou Zhao <jianzhouzh@google.com>
Date: Fri, 26 Feb 2021 23:34:02 +0000 (+0000)
Subject: [msan] Use non-transparent-huge-page at SetShadow
X-Git-Tag: llvmorg-14-init~13890
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c0dc885d29af8f2bd2434047937c2ba65c7c7adb;p=platform%2Fupstream%2Fllvm.git

[msan] Use non-transparent-huge-page at SetShadow

This prevents from getting THP ranges more and more.

Did not see any issues in practice, just found this by code review.

Reviewed By: eugenis, vitalybuka

Differential Revision: https://reviews.llvm.org/D97593
---

diff --git a/compiler-rt/lib/msan/msan_poisoning.cpp b/compiler-rt/lib/msan/msan_poisoning.cpp
index a92b056..1589239 100644
--- a/compiler-rt/lib/msan/msan_poisoning.cpp
+++ b/compiler-rt/lib/msan/msan_poisoning.cpp
@@ -213,7 +213,7 @@ void SetShadow(const void *ptr, uptr size, u8 value) {
       if (page_end != shadow_end) {
         REAL(memset)((void *)page_end, 0, shadow_end - page_end);
       }
-      if (!MmapFixedNoReserve(page_beg, page_end - page_beg))
+      if (!MmapFixedSuperNoReserve(page_beg, page_end - page_beg))
         Die();
     }
   }