Fix redhat arm64 (#52244)

* Fix RHEL 8 ARM64 Clang on ARM64 places the .rodata section into the same segment as .text. On RHEL 8 ARM64, the kernel is configured for 64kB memory pages. When we flip the page protection of the page containing the GS cookie to RW and back to RO, we assume that the cookie lives in a non-executable memory. This assumption is broken on RHEL 8 and we end up setting protection of a part of the coreclr code to read only instead of back to RX. This change switches the linker we use to lld from the previously used gnu linker. That linker places .rodata into a different segment than .text by default. Moreover, I was planning to move to using lld anyways to use all build tools from LLVM. * Fix ARM build to use PC relative addresses only The lld linker has revealed that we were using absolute addresses in some asm helpers and so load time relocation was necessary. This change fixes it by replacing all of those by PC relative ones. * Update docker images used for building runtime Use new images that have lld linker * Disable lld linker for s390x
dotnet · Jul 28, 2021 · 39803d4 · 39803d4
1 parent beaea95
commit 39803d4
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Showing 10 changed files with 51 additions and 27 deletions.
diff --git a/eng/common/templates/jobs/source-build.yml b/eng/common/templates/jobs/source-build.yml
@@ -14,7 +14,7 @@ parameters:
   # This is the default platform provided by Arcade, intended for use by a managed-only repo.
   defaultManagedPlatform:
     name: 'Managed'
-    container: 'mcr.microsoft.com/dotnet-buildtools/prereqs:centos-7-3e800f1-20190501005343'
+    container: 'mcr.microsoft.com/dotnet-buildtools/prereqs:centos-7-20210714125435-9b5bbc2'
 
   # Defines the platforms on which to run build jobs. One job is created for each platform, and the
   # object in this array is sent to the job template as 'platform'. If no platforms are specified,

diff --git a/eng/native/configuretools.cmake b/eng/native/configuretools.cmake
@@ -65,12 +65,14 @@ endif()
 
 if (NOT CLR_CMAKE_HOST_WIN32)
   # detect linker
-  set(ldVersion ${CMAKE_C_COMPILER};-Wl,--version)
+  separate_arguments(ldVersion UNIX_COMMAND "${CMAKE_C_COMPILER} ${CMAKE_SHARED_LINKER_FLAGS} -Wl,--version")
   execute_process(COMMAND ${ldVersion}
     ERROR_QUIET
     OUTPUT_VARIABLE ldVersionOutput)
 
-  if("${ldVersionOutput}" MATCHES "GNU ld" OR "${ldVersionOutput}" MATCHES "GNU gold" OR "${ldVersionOutput}" MATCHES "GNU linkers")
+  if("${ldVersionOutput}" MATCHES "LLD")
+    set(LD_LLVM 1)
+  elseif("${ldVersionOutput}" MATCHES "GNU ld" OR "${ldVersionOutput}" MATCHES "GNU gold" OR "${ldVersionOutput}" MATCHES "GNU linkers")
     set(LD_GNU 1)
   elseif("${ldVersionOutput}" MATCHES "Solaris Link")
     set(LD_SOLARIS 1)

diff --git a/eng/native/functions.cmake b/eng/native/functions.cmake
@@ -157,7 +157,7 @@ function(preprocess_files PreprocessedFilesList)
 endfunction()
 
 function(set_exports_linker_option exports_filename)
-    if(LD_GNU OR LD_SOLARIS)
+    if(LD_GNU OR LD_SOLARIS OR LD_LLVM)
         # Add linker exports file option
         if(LD_SOLARIS)
             set(EXPORTS_LINKER_OPTION -Wl,-M,${exports_filename} PARENT_SCOPE)

diff --git a/eng/native/init-compiler.sh b/eng/native/init-compiler.sh
@@ -22,6 +22,7 @@ minorVersion="$4"
 # clear the existing CC and CXX from environment
 CC=
 CXX=
+LDFLAGS=
 
 if [[ "$compiler" == "gcc" ]]; then cxxCompiler="g++"; fi
 
@@ -106,6 +107,15 @@ if [[ -z "$CC" ]]; then
     exit 1
 fi
 
+if [[ "$compiler" == "clang" ]]; then
+    if command -v "lld$desired_version" > /dev/null; then
+        # Only lld version >= 9 can be considered stable
+        if [[ "$majorVersion" -ge 9 ]]; then
+            LDFLAGS="-fuse-ld=lld"
+        fi
+    fi
+fi
+
 SCAN_BUILD_COMMAND="$(command -v "scan-build$desired_version")"
 
-export CC CXX SCAN_BUILD_COMMAND
+export CC CXX LDFLAGS SCAN_BUILD_COMMAND
diff --git a/eng/pipelines/common/platform-matrix.yml b/eng/pipelines/common/platform-matrix.yml
@@ -38,7 +38,7 @@ jobs:
       targetRid: linux-arm
       platform: Linux_arm
       container:
-        image: ubuntu-16.04-cross-20200413125008-09ec757
+        image: ubuntu-16.04-cross-20210719121212-8a8d3be
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -64,7 +64,7 @@ jobs:
       targetRid: linux-arm64
       platform: Linux_arm64
       container:
-        image: ubuntu-16.04-cross-arm64-20201022204150-b2c2436
+        image: ubuntu-16.04-cross-arm64-20210719121212-8a8d3be
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -91,7 +91,7 @@ jobs:
       targetRid: linux-musl-x64
       platform: Linux_musl_x64
       container:
-        image: alpine-3.9-WithNode-20200602002639-0fc54a3
+        image: alpine-3.9-WithNode-20210714125437-9b5bbc2
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -116,7 +116,7 @@ jobs:
       targetRid: linux-musl-arm
       platform: Linux_musl_arm
       container:
-        image: ubuntu-16.04-cross-arm-alpine-20210409142327-044d5b9
+        image: ubuntu-16.04-cross-arm-alpine-20210719121212-044d5b9
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -143,7 +143,7 @@ jobs:
       targetRid: linux-musl-arm64
       platform: Linux_musl_arm64
       container:
-        image: ubuntu-16.04-cross-arm64-alpine-20200413125008-406629a
+        image: ubuntu-16.04-cross-arm64-alpine-20210719121212-b2c2436
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -169,7 +169,7 @@ jobs:
       targetRid: linux-x64
       platform: Linux_x64
       container:
-        image: centos-7-20201227183837-5fe0e50
+        image: centos-7-20210714125435-9b5bbc2
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}
@@ -193,7 +193,7 @@ jobs:
       targetRid: linux-x64
       platform: Linux_x64
       container:
-        image: centos-7-source-build-20210408124356-5d87b80
+        image: centos-7-source-build-20210714125450-5d87b80
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}

diff --git a/src/coreclr/pgosupport.cmake b/src/coreclr/pgosupport.cmake
@@ -30,7 +30,10 @@ function(add_pgo TargetName)
         else(CLR_CMAKE_HOST_WIN32)
             if(UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELEASE OR UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELWITHDEBINFO)
                 target_compile_options(${TargetName} PRIVATE -flto -fprofile-instr-generate)
-                set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fuse-ld=gold -fprofile-instr-generate")
+                set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fprofile-instr-generate")
+                if(NOT LD_LLVM)
+                    set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -fuse-ld=gold")
+                endif()
             endif(UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELEASE OR UPPERCASE_CMAKE_BUILD_TYPE STREQUAL RELWITHDEBINFO)
         endif(CLR_CMAKE_HOST_WIN32)
     elseif(CLR_CMAKE_PGO_OPTIMIZE)
@@ -61,7 +64,10 @@ function(add_pgo TargetName)
                     if((CMAKE_CXX_COMPILER_ID MATCHES "Clang") AND (NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.6))
                         if(HAVE_LTO)
                             target_compile_options(${TargetName} PRIVATE -flto -fprofile-instr-use=${ProfilePath} -Wno-profile-instr-out-of-date -Wno-profile-instr-unprofiled)
-                            set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fuse-ld=gold -fprofile-instr-use=${ProfilePath}")
+                            set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -flto -fprofile-instr-use=${ProfilePath}")
+                            if(NOT LD_LLVM)
+                                set_property(TARGET ${TargetName} APPEND_STRING PROPERTY LINK_FLAGS " -fuse-ld=gold")
+                            endif()
                         else(HAVE_LTO)
                             message(WARNING "LTO is not supported, skipping profile guided optimizations")
                         endif(HAVE_LTO)

diff --git a/src/coreclr/vm/CMakeLists.txt b/src/coreclr/vm/CMakeLists.txt
@@ -855,7 +855,6 @@ elseif(CLR_CMAKE_TARGET_ARCH_ARM64)
     set(VM_SOURCES_DAC_AND_WKS_ARCH
         ${ARCH_SOURCES_DIR}/stubs.cpp
         exceptionhandling.cpp
-        gcinfodecoder.cpp
     )
 
     set(VM_HEADERS_DAC_AND_WKS_ARCH
@@ -865,6 +864,7 @@ elseif(CLR_CMAKE_TARGET_ARCH_ARM64)
 
     set(VM_SOURCES_WKS_ARCH
         ${ARCH_SOURCES_DIR}/profiler.cpp
+        gcinfodecoder.cpp
     )
 
     if(CLR_CMAKE_HOST_UNIX)

diff --git a/src/coreclr/vm/arm/asmhelpers.S b/src/coreclr/vm/arm/asmhelpers.S
@@ -928,8 +928,9 @@ LOCAL_LABEL(CallCppHelper3):
     .endm
 
     .macro JIT_WRITEBARRIER_DESCRIPTOR name
-        .word \name
-        .word \name\()_End
+1:
+        .word \name-1b
+        .word \name\()_End-1b
         .word __\name\()__g_lowest_address_offset
         .word __\name\()__g_highest_address_offset
         .word __\name\()__g_ephemeral_low_offset
@@ -983,7 +984,9 @@ g_rgWriteBarrierDescriptors:
     LEAF_ENTRY JIT_WriteBarrier_Callable
 
     // Branch to the write barrier
-    ldr     r2, =JIT_WriteBarrier_Loc // or R3? See targetarm.h
+    ldr     r2, =JIT_WriteBarrier_Loc-(1f+4) // or R3? See targetarm.h
+1:
+    add     r2, pc
     ldr     pc, [r2]
 
     LEAF_END JIT_WriteBarrier_Callable

diff --git a/src/coreclr/vm/arm/pinvokestubs.S b/src/coreclr/vm/arm/pinvokestubs.S
@@ -84,15 +84,19 @@
 
         PROLOG_PUSH  "{r4, lr}"
 
-        ldr     r1, =s_gsCookie
+        ldr     r1, =s_gsCookie-(1f+4)
+1:
+        add     r1, pc
         ldr     r1, [r1]
         str     r1, [r0]
         add     r4, r0, SIZEOF__GSCookie
 
         // r4 = pFrame
 
         // set first slot to the value of InlinedCallFrame::`vftable' (checked by runtime code)
-        ldr     r1, .L12
+        ldr     r1, =_ZTV16InlinedCallFrame+8-(2f+4)
+2:
+        add     r1, pc
         str     r1, [r4]
 
         mov     r1, 0
@@ -123,9 +127,6 @@
 
     NESTED_END JIT_PInvokeBegin, _TEXT
 
-.L12:
-    .word   _ZTV16InlinedCallFrame+8
-
 // ------------------------------------------------------------------
 // IN:
 // InlinedCallFrame (r0) = pointer to the InlinedCallFrame data, including the GS cookie slot (GS cookie right
@@ -145,7 +146,9 @@
         str     r2, [r1, #Thread_m_fPreemptiveGCDisabled]
 
         // Check return trap
-        ldr     r2, =g_TrapReturningThreads
+        ldr     r2, =g_TrapReturningThreads-(1f+4)
+1:
+        add     r2, pc
         ldr     r2, [r2]
         cbnz    r2, LOCAL_LABEL(RarePath)
 

diff --git a/src/coreclr/vm/arm/stubs.cpp b/src/coreclr/vm/arm/stubs.cpp
@@ -281,8 +281,8 @@ void StubLinkerCPU::Init(void)
 // value of the global into a register.
 struct WriteBarrierDescriptor
 {
-    BYTE *  m_pFuncStart;                   // Pointer to the start of the barrier function
-    BYTE *  m_pFuncEnd;                     // Pointer to the end of the barrier function
+    DWORD   m_pFuncStart;                   // Offset to the start of the barrier function relative to this struct address
+    DWORD   m_pFuncEnd;                     // Offset to the end of the barrier function relative to this struct address
     DWORD   m_dw_g_lowest_address_offset;   // Offset of the instruction reading g_lowest_address
     DWORD   m_dw_g_highest_address_offset;  // Offset of the instruction reading g_highest_address
     DWORD   m_dw_g_ephemeral_low_offset;    // Offset of the instruction reading g_ephemeral_low
@@ -440,7 +440,7 @@ void UpdateGCWriteBarriers(bool postGrow = false)
     {
         // If the write barrier is being currently used (as in copied over to the patchable site)
         // then read the patch location from the table and use the offset to patch the target asm code
-        PBYTE to = FindWBMapping(pDesc->m_pFuncStart);
+        PBYTE to = FindWBMapping((BYTE *)pDesc + pDesc->m_pFuncStart);
         if(to)
         {
             to = (PBYTE)PCODEToPINSTR((PCODE)GetWriteBarrierCodeLocation(to));