base: support dynamic loading of Linux ELF objects in SE mode

6 files changed, 54 insertions, 28 deletions

diff --git a/src/arch/alpha/process.cc b/src/arch/alpha/process.cc
index 54ef338f3..9e298f0c6 100644
--- a/src/arch/alpha/process.cc
+++ b/src/arch/alpha/process.cc
@@ -67,6 +67,9 @@ AlphaLiveProcess::AlphaLiveProcess(LiveProcessParams *params,
 void
 AlphaLiveProcess::argsInit(int intSize, int pageSize)
 {
+    // Patch the ld_bias for dynamic executables.
+    updateBias();
+
     objFile->loadSections(initVirtMem);
 
     typedef AuxVector<uint64_t> auxv_t;
@@ -88,6 +91,10 @@ AlphaLiveProcess::argsInit(int intSize, int pageSize)
         auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
         DPRINTF(Loader, "auxv at PHDR %08p\n", elfObject->programHeaderTable());
         auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
+        // This is the base address of the ELF interpreter; it should be
+        // zero for static executables or contain the base address for
+        // dynamic executables.
+        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
         auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
         auxv.push_back(auxv_t(M5_AT_UID, uid()));
         auxv.push_back(auxv_t(M5_AT_EUID, euid()));
@@ -163,7 +170,7 @@ AlphaLiveProcess::argsInit(int intSize, int pageSize)
     setSyscallArg(tc, 1, argv_array_base);
     tc->setIntReg(StackPointerReg, stack_min);
 
-    tc->pcState(objFile->entryPoint());
+    tc->pcState(getStartPC());
 }
 
 void
diff --git a/src/arch/arm/process.cc b/src/arch/arm/process.cc
index 0c6f48fb5..a787b1f66 100644
--- a/src/arch/arm/process.cc
+++ b/src/arch/arm/process.cc
@@ -156,6 +156,9 @@ ArmLiveProcess::argsInit(int pageSize, IntRegIndex spIndex)
     //We want 16 byte alignment
     uint64_t align = 16;
 
+    // Patch the ld_bias for dynamic executables.
+    updateBias();
+
     // load object file into target memory
     objFile->loadSections(initVirtMem);
 
@@ -225,10 +228,10 @@ ArmLiveProcess::argsInit(int pageSize, IntRegIndex spIndex)
         auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
         // This is the number of program headers from the original elf file.
         auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
-        //This is the address of the elf "interpreter", It should be set
-        //to 0 for regular executables. It should be something else
-        //(not sure what) for dynamic libraries.
-        auxv.push_back(auxv_t(M5_AT_BASE, 0));
+        // This is the base address of the ELF interpreter; it should be
+        // zero for static executables or contain the base address for
+        // dynamic executables.
+        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
         //XXX Figure out what this should be.
         auxv.push_back(auxv_t(M5_AT_FLAGS, 0));
         //The entry point to the program
@@ -392,7 +395,7 @@ ArmLiveProcess::argsInit(int pageSize, IntRegIndex spIndex)
     pc.nextThumb(pc.thumb());
     pc.aarch64(arch == ObjectFile::Arm64);
     pc.nextAArch64(pc.aarch64());
-    pc.set(objFile->entryPoint() & ~mask(1));
+    pc.set(getStartPC() & ~mask(1));
     tc->pcState(pc);
 
     //Align the "stack_min" to a page boundary.
diff --git a/src/arch/mips/process.cc b/src/arch/mips/process.cc
index 8754191fa..6947eeafd 100644
--- a/src/arch/mips/process.cc
+++ b/src/arch/mips/process.cc
@@ -78,6 +78,9 @@ MipsLiveProcess::argsInit(int pageSize)
 {
     int intSize = sizeof(IntType);
 
+    // Patch the ld_bias for dynamic executables.
+    updateBias();
+
     // load object file into target memory
     objFile->loadSections(initVirtMem);
 
@@ -100,6 +103,10 @@ MipsLiveProcess::argsInit(int pageSize)
         auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
         // This is the number of program headers from the original elf file.
         auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
+        // This is the base address of the ELF interpreter; it should be
+        // zero for static executables or contain the base address for
+        // dynamic executables.
+        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
         //The entry point to the program
         auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
         //Different user and group IDs
@@ -177,7 +184,7 @@ MipsLiveProcess::argsInit(int pageSize)
     setSyscallArg(tc, 1, argv_array_base);
     tc->setIntReg(StackPointerReg, stack_min);
 
-    tc->pcState(objFile->entryPoint());
+    tc->pcState(getStartPC());
 }
 
 
diff --git a/src/arch/power/process.cc b/src/arch/power/process.cc
index a770d8137..10e4a85a0 100644
--- a/src/arch/power/process.cc
+++ b/src/arch/power/process.cc
@@ -85,6 +85,9 @@ PowerLiveProcess::argsInit(int intSize, int pageSize)
     //We want 16 byte alignment
     uint64_t align = 16;
 
+    // Patch the ld_bias for dynamic executables.
+    updateBias();
+
     // load object file into target memory
     objFile->loadSections(initVirtMem);
 
@@ -108,11 +111,10 @@ PowerLiveProcess::argsInit(int intSize, int pageSize)
         auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
         // This is the number of program headers from the original elf file.
         auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
-        //This is the address of the elf "interpreter", It should be set
-        //to 0 for regular executables. It should be something else
-        //(not sure what) for dynamic libraries.
-        auxv.push_back(auxv_t(M5_AT_BASE, 0));
-
+        // This is the base address of the ELF interpreter; it should be
+        // zero for static executables or contain the base address for
+        // dynamic executables.
+        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
         //XXX Figure out what this should be.
         auxv.push_back(auxv_t(M5_AT_FLAGS, 0));
         //The entry point to the program
@@ -255,7 +257,7 @@ PowerLiveProcess::argsInit(int intSize, int pageSize)
     //Set the stack pointer register
     tc->setIntReg(StackPointerReg, stack_min);
 
-    tc->pcState(objFile->entryPoint());
+    tc->pcState(getStartPC());
 
     //Align the "stack_min" to a page boundary.
     stack_min = roundDown(stack_min, pageSize);
diff --git a/src/arch/sparc/process.cc b/src/arch/sparc/process.cc
index 8c8be65ab..09d52ae6b 100644
--- a/src/arch/sparc/process.cc
+++ b/src/arch/sparc/process.cc
@@ -203,6 +203,9 @@ SparcLiveProcess::argsInit(int pageSize)
     // maintain double word alignment of the stack pointer.
     uint64_t align = 16;
 
+    // Patch the ld_bias for dynamic executables.
+    updateBias();
+
     // load object file into target memory
     objFile->loadSections(initVirtMem);
 
@@ -245,10 +248,10 @@ SparcLiveProcess::argsInit(int pageSize)
         auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
         // This is the number of program headers from the original elf file.
         auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
-        // This is the address of the elf "interpreter", It should be set
-        // to 0 for regular executables. It should be something else
-        // (not sure what) for dynamic libraries.
-        auxv.push_back(auxv_t(M5_AT_BASE, 0));
+        // This is the base address of the ELF interpreter; it should be
+        // zero for static executables or contain the base address for
+        // dynamic executables.
+        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
         // This is hardwired to 0 in the elf loading code in the kernel
         auxv.push_back(auxv_t(M5_AT_FLAGS, 0));
         // The entry point to the program
@@ -402,7 +405,7 @@ SparcLiveProcess::argsInit(int pageSize)
     // don't have anything like that, it should be set to 0.
     tc->setIntReg(1, 0);
 
-    tc->pcState(objFile->entryPoint());
+    tc->pcState(getStartPC());
 
     // Align the "stack_min" to a page boundary.
     stack_min = roundDown(stack_min, pageSize);
diff --git a/src/arch/x86/process.cc b/src/arch/x86/process.cc
index d2ce4dbd1..66a520bc3 100644
--- a/src/arch/x86/process.cc
+++ b/src/arch/x86/process.cc
@@ -756,6 +756,9 @@ X86LiveProcess::argsInit(int pageSize,
     //We want 16 byte alignment
     uint64_t align = 16;
 
+    // Patch the ld_bias for dynamic executables.
+    updateBias();
+
     // load object file into target memory
     objFile->loadSections(initVirtMem);
 
@@ -798,8 +801,10 @@ X86LiveProcess::argsInit(int pageSize,
         X86_IA64Processor = 1 << 30
     };
 
-    // Setup the auxilliary vectors. These will already have endian conversion.
-    // Auxilliary vectors are loaded only for elf formatted executables.
+    // Setup the auxiliary vectors. These will already have endian
+    // conversion. Auxiliary vectors are loaded only for elf formatted
+    // executables; the auxv is responsible for passing information from
+    // the OS to the interpreter.
     ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
     if (elfObject) {
         uint64_t features =
@@ -842,18 +847,17 @@ X86LiveProcess::argsInit(int pageSize,
         //Frequency at which times() increments
         //Defined to be 100 in the kernel source.
         auxv.push_back(auxv_t(M5_AT_CLKTCK, 100));
-        // For statically linked executables, this is the virtual address of the
-        // program header tables if they appear in the executable image
+        // This is the virtual address of the program header tables if they
+        // appear in the executable image.
         auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
         // This is the size of a program header entry from the elf file.
         auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
         // This is the number of program headers from the original elf file.
         auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
-        //This is the address of the elf "interpreter", It should be set
-        //to 0 for regular executables. It should be something else
-        //(not sure what) for dynamic libraries.
-        auxv.push_back(auxv_t(M5_AT_BASE, 0));
-
+        // This is the base address of the ELF interpreter; it should be
+        // zero for static executables or contain the base address for
+        // dynamic executables.
+        auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
         //XXX Figure out what this should be.
         auxv.push_back(auxv_t(M5_AT_FLAGS, 0));
         //The entry point to the program
@@ -1014,7 +1018,7 @@ X86LiveProcess::argsInit(int pageSize,
 
     // There doesn't need to be any segment base added in since we're dealing
     // with the flat segmentation model.
-    tc->pcState(objFile->entryPoint());
+    tc->pcState(getStartPC());
 
     //Align the "stack_min" to a page boundary.
     stack_min = roundDown(stack_min, pageSize);