From 6b7d30688d44952fcbb98b3e0f2bfc5155f1f9a5 Mon Sep 17 00:00:00 2001 From: Alec Roelke Date: Tue, 21 Mar 2017 12:56:32 -0400 Subject: riscv: fix compatibility with Linux toolchain Previously, RISC-V in gem5 only supported RISC-V's Newlib toolchain (riscv64-unknown-elf-*) due to incorrect assumptions made in the initial setup of the user stack in SE mode. This patch fixes that by referring to the RISC-V proxy kernel code (https://github.com/riscv/riscv-pk) and setting up the stack according to how it does it. Now binaries compiled using the Linux toolchain (riscv64-unknown-linux-gnu-*) will run as well. [Update for recent changes to MemState to add accessors and mutators to get its members.] Change-Id: I6d2c486df7688efe3df54273e9aa0fd686851285 Reviewed-on: https://gem5-review.googlesource.com/2305 Maintainer: Alec Roelke Reviewed-by: Brandon Potter Reviewed-by: Jason Lowe-Power --- src/arch/riscv/process.cc | 257 +++++++++++++++++++++------------------------- 1 file changed, 116 insertions(+), 141 deletions(-) (limited to 'src/arch/riscv') diff --git a/src/arch/riscv/process.cc b/src/arch/riscv/process.cc index f50fb3196..b9623720e 100644 --- a/src/arch/riscv/process.cc +++ b/src/arch/riscv/process.cc @@ -33,6 +33,11 @@ */ #include "arch/riscv/process.hh" +#include +#include +#include +#include +#include #include #include "arch/riscv/isa_traits.hh" @@ -40,8 +45,9 @@ #include "base/loader/object_file.hh" #include "base/misc.hh" #include "cpu/thread_context.hh" -#include "debug/Loader.hh" +#include "debug/Stack.hh" #include "mem/page_table.hh" +#include "params/Process.hh" #include "sim/aux_vector.hh" #include "sim/process.hh" #include "sim/process_impl.hh" @@ -54,23 +60,15 @@ using namespace RiscvISA; RiscvProcess::RiscvProcess(ProcessParams * params, ObjectFile *objFile) : Process(params, objFile) { - // Set up stack. On RISC-V, stack starts at the top of kuseg - // user address space. RISC-V stack grows down from here - Addr stack_base = 0x7FFFFFFF; - - Addr max_stack_size = 8 * 1024 * 1024; - - // Set pointer for next thread stack. Reserve 8M for main stack. - Addr next_thread_stack_base = stack_base - max_stack_size; - - // Set up break point (Top of Heap) - Addr brk_point = objFile->bssBase() + objFile->bssSize(); - - // Set up region for mmaps. Start it 1GB above the top of the heap. - Addr mmap_end = brk_point + 0x40000000L; - + const Addr mem_base = 0x80000000; + const Addr stack_base = mem_base; + const Addr max_stack_size = PageBytes * 64; + const Addr next_thread_stack_base = stack_base - max_stack_size; + const Addr brk_point = roundUp(objFile->bssBase() + objFile->bssSize(), + PageBytes); + const Addr mmap_end = mem_base; memState = make_shared(brk_point, stack_base, max_stack_size, - next_thread_stack_base, mmap_end); + next_thread_stack_base, mmap_end); } void @@ -85,145 +83,122 @@ template void RiscvProcess::argsInit(int pageSize) { updateBias(); - - // load object file into target memory objFile->loadSections(initVirtMem); - - typedef AuxVector auxv_t; - vector auxv; - ElfObject * elfObject = dynamic_cast(objFile); - if (elfObject) { - // Set the system page size - auxv.push_back(auxv_t(M5_AT_PAGESZ, RiscvISA::PageBytes)); - // Set the frequency at which time() increments - 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. - auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable())); - DPRINTF(Loader, "auxv at PHDR %08p\n", - 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())); - 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 - auxv.push_back(auxv_t(M5_AT_UID, uid())); - auxv.push_back(auxv_t(M5_AT_EUID, euid())); - auxv.push_back(auxv_t(M5_AT_GID, gid())); - auxv.push_back(auxv_t(M5_AT_EGID, egid())); + ElfObject* elfObject = dynamic_cast(objFile); + memState->setStackMin(memState->getStackBase()); + + // Determine stack size and populate auxv + Addr stack_top = memState->getStackMin(); + for (const string& arg: argv) + stack_top -= arg.size() + 1; + for (const string& env: envp) + stack_top -= env.size() + 1; + stack_top &= -sizeof(Addr); + + vector> auxv; + if (elfObject != nullptr) { + auxv.push_back({M5_AT_ENTRY, objFile->entryPoint()}); + auxv.push_back({M5_AT_PHNUM, elfObject->programHeaderCount()}); + auxv.push_back({M5_AT_PHENT, elfObject->programHeaderSize()}); + auxv.push_back({M5_AT_PHDR, elfObject->programHeaderTable()}); + auxv.push_back({M5_AT_PAGESZ, PageBytes}); + auxv.push_back({M5_AT_SECURE, 0}); + auxv.push_back({M5_AT_RANDOM, stack_top}); + auxv.push_back({M5_AT_NULL, 0}); } - - const IntType zero = 0; - IntType argc = htog((IntType)argv.size()); - int argv_array_size = sizeof(Addr) * argv.size(); - int arg_data_size = 0; - for (string arg: argv) - arg_data_size += arg.size() + 1; - int envp_array_size = sizeof(Addr) * envp.size(); - int env_data_size = 0; - for (string env: envp) - env_data_size += env.size() + 1; - int auxv_array_size = 2 * sizeof(IntType)*auxv.size(); - - Addr stack_size = sizeof(IntType) + argv_array_size + 2 * sizeof(Addr) + - sizeof(Addr) + arg_data_size + 2 * sizeof(Addr); - if (!envp.empty()) { - stack_size += 2 * sizeof(Addr) + envp_array_size + 2 * - sizeof(Addr) + env_data_size; + stack_top -= (1 + argv.size()) * sizeof(Addr) + + (1 + envp.size()) * sizeof(Addr) + + sizeof(Addr) + 2 * sizeof(IntType) * auxv.size(); + stack_top &= -2*sizeof(Addr); + memState->setStackSize(memState->getStackBase() - stack_top); + allocateMem(roundDown(stack_top, pageSize), + roundUp(memState->getStackSize(), pageSize)); + + // Copy argv to stack + vector argPointers; + for (const string& arg: argv) { + memState->setStackMin(memState->getStackMin() - (arg.size() + 1)); + initVirtMem.writeString(memState->getStackMin(), arg.c_str()); + argPointers.push_back(memState->getStackMin()); + if (DTRACE(Stack)) { + string wrote; + initVirtMem.readString(wrote, argPointers.back()); + DPRINTFN("Wrote arg \"%s\" to address %p\n", + wrote, (void*)memState->getStackMin()); + } } - if (!auxv.empty()) - stack_size += 2 * sizeof(Addr) + auxv_array_size; - - memState->setStackSize(stack_size); - - Addr stack_min = roundDown(memState->getStackBase() - - stack_size, pageSize); - allocateMem(stack_min, roundUp(memState->getStackSize(), pageSize)); + argPointers.push_back(0); + + // Copy envp to stack + vector envPointers; + for (const string& env: envp) { + memState->setStackMin(memState->getStackMin() - (env.size() + 1)); + initVirtMem.writeString(memState->getStackMin(), env.c_str()); + envPointers.push_back(memState->getStackMin()); + DPRINTF(Stack, "Wrote env \"%s\" to address %p\n", + env, (void*)memState->getStackMin()); + } + envPointers.push_back(0); - memState->setStackMin(stack_min); + // Align stack + memState->setStackMin(memState->getStackMin() & -sizeof(Addr)); - Addr argv_array_base = memState->getStackMin() + sizeof(IntType); - Addr arg_data_base = argv_array_base + argv_array_size + 2 * sizeof(Addr); - Addr envp_array_base = arg_data_base + arg_data_size; - if (!envp.empty()) - envp_array_base += 2 * sizeof(Addr); - Addr env_data_base = envp_array_base + envp_array_size; - if (!envp.empty()) - env_data_base += 2 * sizeof(Addr); + // Calculate bottom of stack + memState->setStackMin(memState->getStackMin() - + ((1 + argv.size()) * sizeof(Addr) + + (1 + envp.size()) * sizeof(Addr) + + sizeof(Addr) + 2 * sizeof(IntType) * auxv.size())); + memState->setStackMin(memState->getStackMin() & -2*sizeof(Addr)); + Addr sp = memState->getStackMin(); + const auto pushOntoStack = + [this, &sp](const uint8_t* data, const size_t size) { + initVirtMem.writeBlob(sp, data, size); + sp += size; + }; - vector arg_pointers; - if (!argv.empty()) { - arg_pointers.push_back(arg_data_base); - for (int i = 0; i < argv.size() - 1; i++) { - arg_pointers.push_back(arg_pointers[i] + argv[i].size() + 1); - } + // Push argc and argv pointers onto stack + IntType argc = htog((IntType)argv.size()); + DPRINTF(Stack, "Wrote argc %d to address %p\n", + argv.size(), (void*)sp); + pushOntoStack((uint8_t*)&argc, sizeof(IntType)); + for (const Addr& argPointer: argPointers) { + DPRINTF(Stack, "Wrote argv pointer %p to address %p\n", + (void*)argPointer, (void*)sp); + pushOntoStack((uint8_t*)&argPointer, sizeof(Addr)); } - vector env_pointers; - if (!envp.empty()) { - env_pointers.push_back(env_data_base); - for (int i = 0; i < envp.size() - 1; i++) { - env_pointers.push_back(env_pointers[i] + envp[i].size() + 1); - } + // Push env pointers onto stack + for (const Addr& envPointer: envPointers) { + DPRINTF(Stack, "Wrote envp pointer %p to address %p\n", + (void*)envPointer, (void*)sp); + pushOntoStack((uint8_t*)&envPointer, sizeof(Addr)); } - Addr sp = memState->getStackMin(); - initVirtMem.writeBlob(sp, (uint8_t *)&argc, sizeof(IntType)); - sp += sizeof(IntType); - for (Addr arg_pointer: arg_pointers) { - initVirtMem.writeBlob(sp, (uint8_t *)&arg_pointer, sizeof(Addr)); - sp += sizeof(Addr); - } - for (int i = 0; i < 2; i++) { - initVirtMem.writeBlob(sp, (uint8_t *)&zero, sizeof(Addr)); - sp += sizeof(Addr); - } - for (int i = 0; i < argv.size(); i++) { - initVirtMem.writeString(sp, argv[i].c_str()); - sp += argv[i].size() + 1; - } - if (!envp.empty()) { - for (int i = 0; i < 2; i++) { - initVirtMem.writeBlob(sp, (uint8_t *)&zero, sizeof(Addr)); - sp += sizeof(Addr); - } - } - for (Addr env_pointer: env_pointers) - initVirtMem.writeBlob(sp, (uint8_t *)&env_pointer, sizeof(Addr)); - if (!envp.empty()) { - for (int i = 0; i < 2; i++) { - initVirtMem.writeBlob(sp, (uint8_t *)&zero, sizeof(Addr)); - sp += sizeof(Addr); - } - } - for (int i = 0; i < envp.size(); i++) { - initVirtMem.writeString(sp, envp[i].c_str()); - sp += envp[i].size() + 1; - } - if (!auxv.empty()) { - for (int i = 0; i < 2; i++) { - initVirtMem.writeBlob(sp, (uint8_t *)&zero, sizeof(Addr)); - sp += sizeof(Addr); - } - } - for (auxv_t aux: auxv) { - initVirtMem.writeBlob(sp, (uint8_t *)&aux.a_type, sizeof(IntType)); - initVirtMem.writeBlob(sp + sizeof(IntType), (uint8_t *)&aux.a_val, - sizeof(IntType)); - sp += 2 * sizeof(IntType); - } - for (int i = 0; i < 2; i++) { - initVirtMem.writeBlob(sp, (uint8_t *)&zero, sizeof(Addr)); - sp += sizeof(Addr); + // Push aux vector onto stack + std::map aux_keys = { + {M5_AT_ENTRY, "M5_AT_ENTRY"}, + {M5_AT_PHNUM, "M5_AT_PHNUM"}, + {M5_AT_PHENT, "M5_AT_PHENT"}, + {M5_AT_PHDR, "M5_AT_PHDR"}, + {M5_AT_PAGESZ, "M5_AT_PAGESZ"}, + {M5_AT_SECURE, "M5_AT_SECURE"}, + {M5_AT_RANDOM, "M5_AT_RANDOM"}, + {M5_AT_NULL, "M5_AT_NULL"} + }; + for (const AuxVector& aux: auxv) { + DPRINTF(Stack, "Wrote aux key %s to address %p\n", + aux_keys[aux.a_type], (void*)sp); + pushOntoStack((uint8_t*)&aux.a_type, sizeof(IntType)); + DPRINTF(Stack, "Wrote aux value %x to address %p\n", + aux.a_val, (void*)sp); + pushOntoStack((uint8_t*)&aux.a_val, sizeof(IntType)); } ThreadContext *tc = system->getThreadContext(contextIds[0]); tc->setIntReg(StackPointerReg, memState->getStackMin()); tc->pcState(getStartPC()); + + memState->setStackMin(roundDown(memState->getStackMin(), pageSize)); } RiscvISA::IntReg -- cgit v1.2.3