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/*
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* Copyright 1999-2007 Sun Microsystems, Inc. All Rights Reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*
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*/
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// do not include precompiled header file
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# include "incls/_os_linux_x86.cpp.incl"
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// put OS-includes here
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# include <sys/types.h>
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# include <sys/mman.h>
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# include <pthread.h>
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# include <signal.h>
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# include <errno.h>
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# include <dlfcn.h>
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# include <stdlib.h>
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# include <stdio.h>
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# include <unistd.h>
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# include <sys/resource.h>
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# include <pthread.h>
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# include <sys/stat.h>
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# include <sys/time.h>
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# include <sys/utsname.h>
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# include <sys/socket.h>
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# include <sys/wait.h>
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# include <pwd.h>
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# include <poll.h>
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# include <ucontext.h>
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# include <fpu_control.h>
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#ifdef AMD64
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#define REG_SP REG_RSP
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#define REG_PC REG_RIP
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#define REG_FP REG_RBP
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#define SPELL_REG_SP "rsp"
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#define SPELL_REG_FP "rbp"
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#else
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#define REG_SP REG_UESP
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#define REG_PC REG_EIP
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#define REG_FP REG_EBP
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#define SPELL_REG_SP "esp"
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#define SPELL_REG_FP "ebp"
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#endif // AMD64
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address os::current_stack_pointer() {
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register void *esp __asm__ (SPELL_REG_SP);
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return (address) esp;
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}
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char* os::non_memory_address_word() {
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// Must never look like an address returned by reserve_memory,
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// even in its subfields (as defined by the CPU immediate fields,
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// if the CPU splits constants across multiple instructions).
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return (char*) -1;
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}
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void os::initialize_thread() {
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// Nothing to do.
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}
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address os::Linux::ucontext_get_pc(ucontext_t * uc) {
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return (address)uc->uc_mcontext.gregs[REG_PC];
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}
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intptr_t* os::Linux::ucontext_get_sp(ucontext_t * uc) {
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return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
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}
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intptr_t* os::Linux::ucontext_get_fp(ucontext_t * uc) {
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return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
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}
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// For Forte Analyzer AsyncGetCallTrace profiling support - thread
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// is currently interrupted by SIGPROF.
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// os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal
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// frames. Currently we don't do that on Linux, so it's the same as
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// os::fetch_frame_from_context().
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ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
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ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
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assert(thread != NULL, "just checking");
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assert(ret_sp != NULL, "just checking");
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assert(ret_fp != NULL, "just checking");
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return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
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}
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ExtendedPC os::fetch_frame_from_context(void* ucVoid,
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intptr_t** ret_sp, intptr_t** ret_fp) {
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ExtendedPC epc;
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ucontext_t* uc = (ucontext_t*)ucVoid;
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if (uc != NULL) {
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epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
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if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc);
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if (ret_fp) *ret_fp = os::Linux::ucontext_get_fp(uc);
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} else {
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// construct empty ExtendedPC for return value checking
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epc = ExtendedPC(NULL);
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if (ret_sp) *ret_sp = (intptr_t *)NULL;
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if (ret_fp) *ret_fp = (intptr_t *)NULL;
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}
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return epc;
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}
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frame os::fetch_frame_from_context(void* ucVoid) {
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intptr_t* sp;
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intptr_t* fp;
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ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
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return frame(sp, fp, epc.pc());
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}
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// By default, gcc always save frame pointer (%ebp/%rbp) on stack. It may get
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// turned off by -fomit-frame-pointer,
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frame os::get_sender_for_C_frame(frame* fr) {
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return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
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}
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intptr_t* _get_previous_fp() {
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register intptr_t **ebp __asm__ (SPELL_REG_FP);
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return (intptr_t*) *ebp; // we want what it points to.
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}
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frame os::current_frame() {
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intptr_t* fp = _get_previous_fp();
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frame myframe((intptr_t*)os::current_stack_pointer(),
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(intptr_t*)fp,
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CAST_FROM_FN_PTR(address, os::current_frame));
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if (os::is_first_C_frame(&myframe)) {
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// stack is not walkable
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return frame(NULL, NULL, NULL);
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} else {
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return os::get_sender_for_C_frame(&myframe);
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}
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}
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// Utility functions
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julong os::allocatable_physical_memory(julong size) {
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#ifdef AMD64
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return size;
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#else
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julong result = MIN2(size, (julong)3800*M);
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if (!is_allocatable(result)) {
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// See comments under solaris for alignment considerations
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julong reasonable_size = (julong)2*G - 2 * os::vm_page_size();
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result = MIN2(size, reasonable_size);
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}
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return result;
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#endif // AMD64
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}
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// From IA32 System Programming Guide
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enum {
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trap_page_fault = 0xE
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};
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extern "C" void Fetch32PFI () ;
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extern "C" void Fetch32Resume () ;
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#ifdef AMD64
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extern "C" void FetchNPFI () ;
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extern "C" void FetchNResume () ;
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#endif // AMD64
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extern "C" int
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JVM_handle_linux_signal(int sig,
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siginfo_t* info,
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void* ucVoid,
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int abort_if_unrecognized) {
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ucontext_t* uc = (ucontext_t*) ucVoid;
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Thread* t = ThreadLocalStorage::get_thread_slow();
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SignalHandlerMark shm(t);
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// Note: it's not uncommon that JNI code uses signal/sigset to install
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// then restore certain signal handler (e.g. to temporarily block SIGPIPE,
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// or have a SIGILL handler when detecting CPU type). When that happens,
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// JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
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// avoid unnecessary crash when libjsig is not preloaded, try handle signals
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// that do not require siginfo/ucontext first.
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if (sig == SIGPIPE || sig == SIGXFSZ) {
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// allow chained handler to go first
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if (os::Linux::chained_handler(sig, info, ucVoid)) {
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return true;
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} else {
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if (PrintMiscellaneous && (WizardMode || Verbose)) {
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char buf[64];
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warning("Ignoring %s - see bugs 4229104 or 646499219",
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os::exception_name(sig, buf, sizeof(buf)));
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}
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return true;
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}
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}
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JavaThread* thread = NULL;
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VMThread* vmthread = NULL;
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if (os::Linux::signal_handlers_are_installed) {
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if (t != NULL ){
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if(t->is_Java_thread()) {
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thread = (JavaThread*)t;
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}
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else if(t->is_VM_thread()){
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vmthread = (VMThread *)t;
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}
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}
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}
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/*
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NOTE: does not seem to work on linux.
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if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
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// can't decode this kind of signal
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info = NULL;
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} else {
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assert(sig == info->si_signo, "bad siginfo");
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}
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*/
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// decide if this trap can be handled by a stub
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address stub = NULL;
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address pc = NULL;
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//%note os_trap_1
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if (info != NULL && uc != NULL && thread != NULL) {
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pc = (address) os::Linux::ucontext_get_pc(uc);
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if (pc == (address) Fetch32PFI) {
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uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ;
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return 1 ;
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}
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#ifdef AMD64
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if (pc == (address) FetchNPFI) {
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uc->uc_mcontext.gregs[REG_PC] = intptr_t (FetchNResume) ;
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return 1 ;
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}
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#endif // AMD64
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// Handle ALL stack overflow variations here
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if (sig == SIGSEGV) {
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address addr = (address) info->si_addr;
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// check if fault address is within thread stack
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if (addr < thread->stack_base() &&
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addr >= thread->stack_base() - thread->stack_size()) {
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// stack overflow
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if (thread->in_stack_yellow_zone(addr)) {
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thread->disable_stack_yellow_zone();
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if (thread->thread_state() == _thread_in_Java) {
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// Throw a stack overflow exception. Guard pages will be reenabled
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// while unwinding the stack.
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stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
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} else {
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// Thread was in the vm or native code. Return and try to finish.
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return 1;
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}
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} else if (thread->in_stack_red_zone(addr)) {
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// Fatal red zone violation. Disable the guard pages and fall through
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// to handle_unexpected_exception way down below.
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thread->disable_stack_red_zone();
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tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
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} else {
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// Accessing stack address below sp may cause SEGV if current
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// thread has MAP_GROWSDOWN stack. This should only happen when
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// current thread was created by user code with MAP_GROWSDOWN flag
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// and then attached to VM. See notes in os_linux.cpp.
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if (thread->osthread()->expanding_stack() == 0) {
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thread->osthread()->set_expanding_stack();
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if (os::Linux::manually_expand_stack(thread, addr)) {
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thread->osthread()->clear_expanding_stack();
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return 1;
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}
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thread->osthread()->clear_expanding_stack();
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} else {
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fatal("recursive segv. expanding stack.");
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}
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}
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}
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}
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if (thread->thread_state() == _thread_in_Java) {
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// Java thread running in Java code => find exception handler if any
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// a fault inside compiled code, the interpreter, or a stub
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if (sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
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stub = SharedRuntime::get_poll_stub(pc);
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} else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) {
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// BugId 4454115: A read from a MappedByteBuffer can fault
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// here if the underlying file has been truncated.
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// Do not crash the VM in such a case.
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CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
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nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
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if (nm != NULL && nm->has_unsafe_access()) {
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stub = StubRoutines::handler_for_unsafe_access();
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}
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}
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else
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#ifdef AMD64
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if (sig == SIGFPE &&
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(info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) {
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stub =
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SharedRuntime::
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continuation_for_implicit_exception(thread,
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pc,
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SharedRuntime::
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IMPLICIT_DIVIDE_BY_ZERO);
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#else
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if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) {
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// HACK: si_code does not work on linux 2.2.12-20!!!
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int op = pc[0];
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if (op == 0xDB) {
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// FIST
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// TODO: The encoding of D2I in i486.ad can cause an exception
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// prior to the fist instruction if there was an invalid operation
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// pending. We want to dismiss that exception. From the win_32
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// side it also seems that if it really was the fist causing
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// the exception that we do the d2i by hand with different
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// rounding. Seems kind of weird.
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// NOTE: that we take the exception at the NEXT floating point instruction.
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assert(pc[0] == 0xDB, "not a FIST opcode");
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assert(pc[1] == 0x14, "not a FIST opcode");
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assert(pc[2] == 0x24, "not a FIST opcode");
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return true;
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} else if (op == 0xF7) {
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// IDIV
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stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
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} else {
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// TODO: handle more cases if we are using other x86 instructions
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// that can generate SIGFPE signal on linux.
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tty->print_cr("unknown opcode 0x%X with SIGFPE.", op);
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fatal("please update this code.");
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}
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#endif // AMD64
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} else if (sig == SIGSEGV &&
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!MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
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// Determination of interpreter/vtable stub/compiled code null exception
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stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
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}
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} else if (thread->thread_state() == _thread_in_vm &&
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sig == SIGBUS && /* info->si_code == BUS_OBJERR && */
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thread->doing_unsafe_access()) {
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stub = StubRoutines::handler_for_unsafe_access();
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}
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// jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
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// and the heap gets shrunk before the field access.
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if ((sig == SIGSEGV) || (sig == SIGBUS)) {
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address addr = JNI_FastGetField::find_slowcase_pc(pc);
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if (addr != (address)-1) {
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stub = addr;
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}
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}
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// Check to see if we caught the safepoint code in the
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// process of write protecting the memory serialization page.
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// It write enables the page immediately after protecting it
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// so we can just return to retry the write.
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if ((sig == SIGSEGV) &&
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os::is_memory_serialize_page(thread, (address) info->si_addr)) {
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// Block current thread until the memory serialize page permission restored.
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os::block_on_serialize_page_trap();
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return true;
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}
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388 |
}
|
|
389 |
|
|
390 |
#ifndef AMD64
|
|
391 |
// Execution protection violation
|
|
392 |
//
|
|
393 |
// This should be kept as the last step in the triage. We don't
|
|
394 |
// have a dedicated trap number for a no-execute fault, so be
|
|
395 |
// conservative and allow other handlers the first shot.
|
|
396 |
//
|
|
397 |
// Note: We don't test that info->si_code == SEGV_ACCERR here.
|
|
398 |
// this si_code is so generic that it is almost meaningless; and
|
|
399 |
// the si_code for this condition may change in the future.
|
|
400 |
// Furthermore, a false-positive should be harmless.
|
|
401 |
if (UnguardOnExecutionViolation > 0 &&
|
|
402 |
(sig == SIGSEGV || sig == SIGBUS) &&
|
|
403 |
uc->uc_mcontext.gregs[REG_TRAPNO] == trap_page_fault) {
|
|
404 |
int page_size = os::vm_page_size();
|
|
405 |
address addr = (address) info->si_addr;
|
|
406 |
address pc = os::Linux::ucontext_get_pc(uc);
|
|
407 |
// Make sure the pc and the faulting address are sane.
|
|
408 |
//
|
|
409 |
// If an instruction spans a page boundary, and the page containing
|
|
410 |
// the beginning of the instruction is executable but the following
|
|
411 |
// page is not, the pc and the faulting address might be slightly
|
|
412 |
// different - we still want to unguard the 2nd page in this case.
|
|
413 |
//
|
|
414 |
// 15 bytes seems to be a (very) safe value for max instruction size.
|
|
415 |
bool pc_is_near_addr =
|
|
416 |
(pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
|
|
417 |
bool instr_spans_page_boundary =
|
|
418 |
(align_size_down((intptr_t) pc ^ (intptr_t) addr,
|
|
419 |
(intptr_t) page_size) > 0);
|
|
420 |
|
|
421 |
if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
|
|
422 |
static volatile address last_addr =
|
|
423 |
(address) os::non_memory_address_word();
|
|
424 |
|
|
425 |
// In conservative mode, don't unguard unless the address is in the VM
|
|
426 |
if (addr != last_addr &&
|
|
427 |
(UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
|
|
428 |
|
|
429 |
// Unguard and retry
|
|
430 |
address page_start =
|
|
431 |
(address) align_size_down((intptr_t) addr, (intptr_t) page_size);
|
|
432 |
bool res = os::unguard_memory((char*) page_start, page_size);
|
|
433 |
|
|
434 |
if (PrintMiscellaneous && Verbose) {
|
|
435 |
char buf[256];
|
|
436 |
jio_snprintf(buf, sizeof(buf), "Execution protection violation "
|
|
437 |
"at " INTPTR_FORMAT
|
|
438 |
", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
|
|
439 |
page_start, (res ? "success" : "failed"), errno);
|
|
440 |
tty->print_raw_cr(buf);
|
|
441 |
}
|
|
442 |
stub = pc;
|
|
443 |
|
|
444 |
// Set last_addr so if we fault again at the same address, we don't end
|
|
445 |
// up in an endless loop.
|
|
446 |
//
|
|
447 |
// There are two potential complications here. Two threads trapping at
|
|
448 |
// the same address at the same time could cause one of the threads to
|
|
449 |
// think it already unguarded, and abort the VM. Likely very rare.
|
|
450 |
//
|
|
451 |
// The other race involves two threads alternately trapping at
|
|
452 |
// different addresses and failing to unguard the page, resulting in
|
|
453 |
// an endless loop. This condition is probably even more unlikely than
|
|
454 |
// the first.
|
|
455 |
//
|
|
456 |
// Although both cases could be avoided by using locks or thread local
|
|
457 |
// last_addr, these solutions are unnecessary complication: this
|
|
458 |
// handler is a best-effort safety net, not a complete solution. It is
|
|
459 |
// disabled by default and should only be used as a workaround in case
|
|
460 |
// we missed any no-execute-unsafe VM code.
|
|
461 |
|
|
462 |
last_addr = addr;
|
|
463 |
}
|
|
464 |
}
|
|
465 |
}
|
|
466 |
#endif // !AMD64
|
|
467 |
|
|
468 |
if (stub != NULL) {
|
|
469 |
// save all thread context in case we need to restore it
|
|
470 |
if (thread != NULL) thread->set_saved_exception_pc(pc);
|
|
471 |
|
|
472 |
uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub;
|
|
473 |
return true;
|
|
474 |
}
|
|
475 |
|
|
476 |
// signal-chaining
|
|
477 |
if (os::Linux::chained_handler(sig, info, ucVoid)) {
|
|
478 |
return true;
|
|
479 |
}
|
|
480 |
|
|
481 |
if (!abort_if_unrecognized) {
|
|
482 |
// caller wants another chance, so give it to him
|
|
483 |
return false;
|
|
484 |
}
|
|
485 |
|
|
486 |
if (pc == NULL && uc != NULL) {
|
|
487 |
pc = os::Linux::ucontext_get_pc(uc);
|
|
488 |
}
|
|
489 |
|
|
490 |
// unmask current signal
|
|
491 |
sigset_t newset;
|
|
492 |
sigemptyset(&newset);
|
|
493 |
sigaddset(&newset, sig);
|
|
494 |
sigprocmask(SIG_UNBLOCK, &newset, NULL);
|
|
495 |
|
|
496 |
VMError err(t, sig, pc, info, ucVoid);
|
|
497 |
err.report_and_die();
|
|
498 |
|
|
499 |
ShouldNotReachHere();
|
|
500 |
}
|
|
501 |
|
|
502 |
void os::Linux::init_thread_fpu_state(void) {
|
|
503 |
#ifndef AMD64
|
|
504 |
// set fpu to 53 bit precision
|
|
505 |
set_fpu_control_word(0x27f);
|
|
506 |
#endif // !AMD64
|
|
507 |
}
|
|
508 |
|
|
509 |
int os::Linux::get_fpu_control_word(void) {
|
|
510 |
#ifdef AMD64
|
|
511 |
return 0;
|
|
512 |
#else
|
|
513 |
int fpu_control;
|
|
514 |
_FPU_GETCW(fpu_control);
|
|
515 |
return fpu_control & 0xffff;
|
|
516 |
#endif // AMD64
|
|
517 |
}
|
|
518 |
|
|
519 |
void os::Linux::set_fpu_control_word(int fpu_control) {
|
|
520 |
#ifndef AMD64
|
|
521 |
_FPU_SETCW(fpu_control);
|
|
522 |
#endif // !AMD64
|
|
523 |
}
|
|
524 |
|
|
525 |
// Check that the linux kernel version is 2.4 or higher since earlier
|
|
526 |
// versions do not support SSE without patches.
|
|
527 |
bool os::supports_sse() {
|
|
528 |
#ifdef AMD64
|
|
529 |
return true;
|
|
530 |
#else
|
|
531 |
struct utsname uts;
|
|
532 |
if( uname(&uts) != 0 ) return false; // uname fails?
|
|
533 |
char *minor_string;
|
|
534 |
int major = strtol(uts.release,&minor_string,10);
|
|
535 |
int minor = strtol(minor_string+1,NULL,10);
|
|
536 |
bool result = (major > 2 || (major==2 && minor >= 4));
|
|
537 |
#ifndef PRODUCT
|
|
538 |
if (PrintMiscellaneous && Verbose) {
|
|
539 |
tty->print("OS version is %d.%d, which %s support SSE/SSE2\n",
|
|
540 |
major,minor, result ? "DOES" : "does NOT");
|
|
541 |
}
|
|
542 |
#endif
|
|
543 |
return result;
|
|
544 |
#endif // AMD64
|
|
545 |
}
|
|
546 |
|
|
547 |
bool os::is_allocatable(size_t bytes) {
|
|
548 |
#ifdef AMD64
|
|
549 |
// unused on amd64?
|
|
550 |
return true;
|
|
551 |
#else
|
|
552 |
|
|
553 |
if (bytes < 2 * G) {
|
|
554 |
return true;
|
|
555 |
}
|
|
556 |
|
|
557 |
char* addr = reserve_memory(bytes, NULL);
|
|
558 |
|
|
559 |
if (addr != NULL) {
|
|
560 |
release_memory(addr, bytes);
|
|
561 |
}
|
|
562 |
|
|
563 |
return addr != NULL;
|
|
564 |
#endif // AMD64
|
|
565 |
}
|
|
566 |
|
|
567 |
////////////////////////////////////////////////////////////////////////////////
|
|
568 |
// thread stack
|
|
569 |
|
|
570 |
#ifdef AMD64
|
|
571 |
size_t os::Linux::min_stack_allowed = 64 * K;
|
|
572 |
|
|
573 |
// amd64: pthread on amd64 is always in floating stack mode
|
|
574 |
bool os::Linux::supports_variable_stack_size() { return true; }
|
|
575 |
#else
|
|
576 |
size_t os::Linux::min_stack_allowed = (48 DEBUG_ONLY(+4))*K;
|
|
577 |
|
|
578 |
#define GET_GS() ({int gs; __asm__ volatile("movw %%gs, %w0":"=q"(gs)); gs&0xffff;})
|
|
579 |
|
|
580 |
// Test if pthread library can support variable thread stack size. LinuxThreads
|
|
581 |
// in fixed stack mode allocates 2M fixed slot for each thread. LinuxThreads
|
|
582 |
// in floating stack mode and NPTL support variable stack size.
|
|
583 |
bool os::Linux::supports_variable_stack_size() {
|
|
584 |
if (os::Linux::is_NPTL()) {
|
|
585 |
// NPTL, yes
|
|
586 |
return true;
|
|
587 |
|
|
588 |
} else {
|
|
589 |
// Note: We can't control default stack size when creating a thread.
|
|
590 |
// If we use non-default stack size (pthread_attr_setstacksize), both
|
|
591 |
// floating stack and non-floating stack LinuxThreads will return the
|
|
592 |
// same value. This makes it impossible to implement this function by
|
|
593 |
// detecting thread stack size directly.
|
|
594 |
//
|
|
595 |
// An alternative approach is to check %gs. Fixed-stack LinuxThreads
|
|
596 |
// do not use %gs, so its value is 0. Floating-stack LinuxThreads use
|
|
597 |
// %gs (either as LDT selector or GDT selector, depending on kernel)
|
|
598 |
// to access thread specific data.
|
|
599 |
//
|
|
600 |
// Note that %gs is a reserved glibc register since early 2001, so
|
|
601 |
// applications are not allowed to change its value (Ulrich Drepper from
|
|
602 |
// Redhat confirmed that all known offenders have been modified to use
|
|
603 |
// either %fs or TSD). In the worst case scenario, when VM is embedded in
|
|
604 |
// a native application that plays with %gs, we might see non-zero %gs
|
|
605 |
// even LinuxThreads is running in fixed stack mode. As the result, we'll
|
|
606 |
// return true and skip _thread_safety_check(), so we may not be able to
|
|
607 |
// detect stack-heap collisions. But otherwise it's harmless.
|
|
608 |
//
|
|
609 |
return (GET_GS() != 0);
|
|
610 |
}
|
|
611 |
}
|
|
612 |
#endif // AMD64
|
|
613 |
|
|
614 |
// return default stack size for thr_type
|
|
615 |
size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
|
|
616 |
// default stack size (compiler thread needs larger stack)
|
|
617 |
#ifdef AMD64
|
|
618 |
size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
|
|
619 |
#else
|
|
620 |
size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
|
|
621 |
#endif // AMD64
|
|
622 |
return s;
|
|
623 |
}
|
|
624 |
|
|
625 |
size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
|
|
626 |
// Creating guard page is very expensive. Java thread has HotSpot
|
|
627 |
// guard page, only enable glibc guard page for non-Java threads.
|
|
628 |
return (thr_type == java_thread ? 0 : page_size());
|
|
629 |
}
|
|
630 |
|
|
631 |
// Java thread:
|
|
632 |
//
|
|
633 |
// Low memory addresses
|
|
634 |
// +------------------------+
|
|
635 |
// | |\ JavaThread created by VM does not have glibc
|
|
636 |
// | glibc guard page | - guard, attached Java thread usually has
|
|
637 |
// | |/ 1 page glibc guard.
|
|
638 |
// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
|
|
639 |
// | |\
|
|
640 |
// | HotSpot Guard Pages | - red and yellow pages
|
|
641 |
// | |/
|
|
642 |
// +------------------------+ JavaThread::stack_yellow_zone_base()
|
|
643 |
// | |\
|
|
644 |
// | Normal Stack | -
|
|
645 |
// | |/
|
|
646 |
// P2 +------------------------+ Thread::stack_base()
|
|
647 |
//
|
|
648 |
// Non-Java thread:
|
|
649 |
//
|
|
650 |
// Low memory addresses
|
|
651 |
// +------------------------+
|
|
652 |
// | |\
|
|
653 |
// | glibc guard page | - usually 1 page
|
|
654 |
// | |/
|
|
655 |
// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
|
|
656 |
// | |\
|
|
657 |
// | Normal Stack | -
|
|
658 |
// | |/
|
|
659 |
// P2 +------------------------+ Thread::stack_base()
|
|
660 |
//
|
|
661 |
// ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
|
|
662 |
// pthread_attr_getstack()
|
|
663 |
|
|
664 |
static void current_stack_region(address * bottom, size_t * size) {
|
|
665 |
if (os::Linux::is_initial_thread()) {
|
|
666 |
// initial thread needs special handling because pthread_getattr_np()
|
|
667 |
// may return bogus value.
|
|
668 |
*bottom = os::Linux::initial_thread_stack_bottom();
|
|
669 |
*size = os::Linux::initial_thread_stack_size();
|
|
670 |
} else {
|
|
671 |
pthread_attr_t attr;
|
|
672 |
|
|
673 |
int rslt = pthread_getattr_np(pthread_self(), &attr);
|
|
674 |
|
|
675 |
// JVM needs to know exact stack location, abort if it fails
|
|
676 |
if (rslt != 0) {
|
|
677 |
if (rslt == ENOMEM) {
|
|
678 |
vm_exit_out_of_memory(0, "pthread_getattr_np");
|
|
679 |
} else {
|
|
680 |
fatal1("pthread_getattr_np failed with errno = %d", rslt);
|
|
681 |
}
|
|
682 |
}
|
|
683 |
|
|
684 |
if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
|
|
685 |
fatal("Can not locate current stack attributes!");
|
|
686 |
}
|
|
687 |
|
|
688 |
pthread_attr_destroy(&attr);
|
|
689 |
|
|
690 |
}
|
|
691 |
assert(os::current_stack_pointer() >= *bottom &&
|
|
692 |
os::current_stack_pointer() < *bottom + *size, "just checking");
|
|
693 |
}
|
|
694 |
|
|
695 |
address os::current_stack_base() {
|
|
696 |
address bottom;
|
|
697 |
size_t size;
|
|
698 |
current_stack_region(&bottom, &size);
|
|
699 |
return (bottom + size);
|
|
700 |
}
|
|
701 |
|
|
702 |
size_t os::current_stack_size() {
|
|
703 |
// stack size includes normal stack and HotSpot guard pages
|
|
704 |
address bottom;
|
|
705 |
size_t size;
|
|
706 |
current_stack_region(&bottom, &size);
|
|
707 |
return size;
|
|
708 |
}
|
|
709 |
|
|
710 |
/////////////////////////////////////////////////////////////////////////////
|
|
711 |
// helper functions for fatal error handler
|
|
712 |
|
|
713 |
void os::print_context(outputStream *st, void *context) {
|
|
714 |
if (context == NULL) return;
|
|
715 |
|
|
716 |
ucontext_t *uc = (ucontext_t*)context;
|
|
717 |
st->print_cr("Registers:");
|
|
718 |
#ifdef AMD64
|
|
719 |
st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
|
|
720 |
st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
|
|
721 |
st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
|
|
722 |
st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
|
|
723 |
st->cr();
|
|
724 |
st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
|
|
725 |
st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
|
|
726 |
st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
|
|
727 |
st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
|
|
728 |
st->cr();
|
|
729 |
st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
|
|
730 |
st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
|
|
731 |
st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
|
|
732 |
st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
|
|
733 |
st->cr();
|
|
734 |
st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
|
|
735 |
st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
|
|
736 |
st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
|
|
737 |
st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
|
|
738 |
st->cr();
|
|
739 |
st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
|
|
740 |
st->print(", EFL=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EFL]);
|
|
741 |
st->print(", CSGSFS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_CSGSFS]);
|
|
742 |
st->print(", ERR=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_ERR]);
|
|
743 |
st->cr();
|
|
744 |
st->print(" TRAPNO=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_TRAPNO]);
|
|
745 |
#else
|
|
746 |
st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EAX]);
|
|
747 |
st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EBX]);
|
|
748 |
st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_ECX]);
|
|
749 |
st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EDX]);
|
|
750 |
st->cr();
|
|
751 |
st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_UESP]);
|
|
752 |
st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EBP]);
|
|
753 |
st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_ESI]);
|
|
754 |
st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EDI]);
|
|
755 |
st->cr();
|
|
756 |
st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EIP]);
|
|
757 |
st->print(", CR2=" INTPTR_FORMAT, uc->uc_mcontext.cr2);
|
|
758 |
st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EFL]);
|
|
759 |
#endif // AMD64
|
|
760 |
st->cr();
|
|
761 |
st->cr();
|
|
762 |
|
|
763 |
intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
|
|
764 |
st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
|
|
765 |
print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
|
|
766 |
st->cr();
|
|
767 |
|
|
768 |
// Note: it may be unsafe to inspect memory near pc. For example, pc may
|
|
769 |
// point to garbage if entry point in an nmethod is corrupted. Leave
|
|
770 |
// this at the end, and hope for the best.
|
|
771 |
address pc = os::Linux::ucontext_get_pc(uc);
|
|
772 |
st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
|
|
773 |
print_hex_dump(st, pc - 16, pc + 16, sizeof(char));
|
|
774 |
}
|
|
775 |
|
|
776 |
void os::setup_fpu() {
|
|
777 |
#ifndef AMD64
|
|
778 |
address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
|
|
779 |
__asm__ volatile ( "fldcw (%0)" :
|
|
780 |
: "r" (fpu_cntrl) : "memory");
|
|
781 |
#endif // !AMD64
|
|
782 |
}
|