1 files changed, 117 insertions, 0 deletions
diff --git a/packaging/0035-PEImageLayout-flush-instruction-cache-only-for-pages.patch b/packaging/0035-PEImageLayout-flush-instruction-cache-only-for-pages.patch
new file mode 100644
index 0000000000..e986952668
--- /dev/null
+++ b/packaging/0035-PEImageLayout-flush-instruction-cache-only-for-pages.patch
@@ -0,0 +1,117 @@
+From c5539d864c61476446542bee351af3a125118ef3 Mon Sep 17 00:00:00 2001
+From: Konstantin Baladurin <k.baladurin@partner.samsung.com>
+Date: Mon, 14 May 2018 12:35:09 +0300
+Subject: [PATCH 35/47] PEImageLayout: flush instruction cache only for pages
+ with relocs.
+
+We need to flush instruction cache only for pages that have relocations
+instead of full sections because otherwise application's shared clean
+memory is increased in some cases on Linux.
+---
+ src/vm/peimagelayout.cpp | 46 +++++++++++++++++++++++++++++-----------------
+ 1 file changed, 29 insertions(+), 17 deletions(-)
+
+diff --git a/src/vm/peimagelayout.cpp b/src/vm/peimagelayout.cpp
+index 4bfbe40..5e0243b 100644
+--- a/src/vm/peimagelayout.cpp
++++ b/src/vm/peimagelayout.cpp
+@@ -150,7 +150,10 @@ void PEImageLayout::ApplyBaseRelocations()
+     SIZE_T cbWriteableRegion = 0;
+     DWORD dwOldProtection = 0;
+ 
+-    BOOL bRelocDone = FALSE;
++    BYTE * pFlushRegion = NULL;
++    SIZE_T cbFlushRegion = 0;
++    // The page size of PE file relocs is always 4096 bytes
++    const SIZE_T cbPageSize = 4096;
+ 
+     COUNT_T dirPos = 0;
+     while (dirPos < dirSize)
+@@ -185,13 +188,6 @@ void PEImageLayout::ApplyBaseRelocations()
+                                        dwOldProtection, &dwOldProtection))
+                     ThrowLastError();
+ 
+-                if (bRelocDone && bExecRegion)
+-                {
+-                    ClrFlushInstructionCache(pWriteableRegion, cbWriteableRegion);
+-                }
+-
+-                bRelocDone = FALSE;
+-
+                 dwOldProtection = 0;
+             }
+ 
+@@ -224,6 +220,7 @@ void PEImageLayout::ApplyBaseRelocations()
+             }
+         }
+ 
++        BYTE* pEndAddressToFlush = NULL;
+         for (COUNT_T fixupIndex = 0; fixupIndex < fixupsCount; fixupIndex++)
+         {
+             USHORT fixup = VAL16(fixups[fixupIndex]);
+@@ -234,13 +231,13 @@ void PEImageLayout::ApplyBaseRelocations()
+             {
+             case IMAGE_REL_BASED_PTR:
+                 *(TADDR *)address += delta;
+-                bRelocDone = TRUE;
++                pEndAddressToFlush = max(pEndAddressToFlush, address + sizeof(TADDR));
+                 break;
+ 
+ #ifdef _TARGET_ARM_
+             case IMAGE_REL_BASED_THUMB_MOV32:
+                 PutThumb2Mov32((UINT16 *)address, GetThumb2Mov32((UINT16 *)address) + delta);
+-                bRelocDone = TRUE;
++                pEndAddressToFlush = max(pEndAddressToFlush, address + 8);
+                 break;
+ #endif
+ 
+@@ -253,24 +250,39 @@ void PEImageLayout::ApplyBaseRelocations()
+             }
+         }
+ 
++        BOOL bExecRegion = (dwOldProtection & (PAGE_EXECUTE | PAGE_EXECUTE_READ |
++            PAGE_EXECUTE_READWRITE | PAGE_EXECUTE_WRITECOPY)) != 0;
++
++        if (bExecRegion && pEndAddressToFlush != NULL)
++        {
++            // If the current page is not next to the pending region to flush, flush the current pending region and start a new one
++            if (pageAddress >= pFlushRegion + cbFlushRegion + cbPageSize || pageAddress < pFlushRegion)
++            {
++                if (pFlushRegion != NULL)
++                {
++                    ClrFlushInstructionCache(pFlushRegion, cbFlushRegion);
++                }
++                pFlushRegion = pageAddress;
++            }
++
++            cbFlushRegion = pEndAddressToFlush - pFlushRegion;
++        }
++
+         dirPos += fixupsSize;
+     }
+     _ASSERTE(dirSize == dirPos);
+ 
+     if (dwOldProtection != 0)
+     {
+-        BOOL bExecRegion = (dwOldProtection & (PAGE_EXECUTE | PAGE_EXECUTE_READ |
+-            PAGE_EXECUTE_READWRITE | PAGE_EXECUTE_WRITECOPY)) != 0;
+-
+         // Restore the protection
+         if (!ClrVirtualProtect(pWriteableRegion, cbWriteableRegion,
+                                dwOldProtection, &dwOldProtection))
+             ThrowLastError();
++    }
+ 
+-        if (bRelocDone && bExecRegion)
+-        {
+-            ClrFlushInstructionCache(pWriteableRegion, cbWriteableRegion);
+-        }
++    if (pFlushRegion != NULL)
++    {
++        ClrFlushInstructionCache(pFlushRegion, cbFlushRegion);
+     }
+ }
+ #endif // FEATURE_PREJIT
+-- 
+2.7.4
+