jdk8-mips64-public/hotspot: src/os_cpu/linux_x86/vm/thread_linux

8023956: Provide a work-around to broken Linux 32 bit "Exec Shield" using CS for NX emulation (crashing with SI_KERNEL)
Summary: Execute some code at a high virtual address value, and keep mapped
Reviewed-by: coleenp, zgu

     1 /*

     2  * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  *

    23  */

    25 #include "precompiled.hpp"

    26 #include "runtime/frame.inline.hpp"

    27 #include "runtime/thread.inline.hpp"

    29 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is

    30 // currently interrupted by SIGPROF

    31 bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,

    32   void* ucontext, bool isInJava) {

    34   assert(Thread::current() == this, "caller must be current thread");

    35   return pd_get_top_frame(fr_addr, ucontext, isInJava);

    36 }

    38 bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) {

    39   return pd_get_top_frame(fr_addr, ucontext, isInJava);

    40 }

    42 bool JavaThread::pd_get_top_frame(frame* fr_addr, void* ucontext, bool isInJava) {

    43   assert(this->is_Java_thread(), "must be JavaThread");

    44   JavaThread* jt = (JavaThread *)this;

    46   // If we have a last_Java_frame, then we should use it even if

    47   // isInJava == true.  It should be more reliable than ucontext info.

    48   if (jt->has_last_Java_frame()) {

    49     *fr_addr = jt->pd_last_frame();

    50     return true;

    51   }

    53   // At this point, we don't have a last_Java_frame, so

    54   // we try to glean some information out of the ucontext

    55   // if we were running Java code when SIGPROF came in.

    56   if (isInJava) {

    57     ucontext_t* uc = (ucontext_t*) ucontext;

    59     intptr_t* ret_fp;

    60     intptr_t* ret_sp;

    61     ExtendedPC addr = os::Linux::fetch_frame_from_ucontext(this, uc,

    62       &ret_sp, &ret_fp);

    63     if (addr.pc() == NULL || ret_sp == NULL ) {

    64       // ucontext wasn't useful

    65       return false;

    66     }

    68     frame ret_frame(ret_sp, ret_fp, addr.pc());

    69     if (!ret_frame.safe_for_sender(jt)) {

    70 #ifdef COMPILER2

    71       // C2 uses ebp as a general register see if NULL fp helps

    72       frame ret_frame2(ret_sp, NULL, addr.pc());

    73       if (!ret_frame2.safe_for_sender(jt)) {

    74         // nothing else to try if the frame isn't good

    75         return false;

    76       }

    77       ret_frame = ret_frame2;

    78 #else

    79       // nothing else to try if the frame isn't good

    80       return false;

    81 #endif /* COMPILER2 */

    82     }

    83     *fr_addr = ret_frame;

    84     return true;

    85   }

    87   // nothing else to try

    88   return false;

    89 }

    91 void JavaThread::cache_global_variables() { }

src/os_cpu/linux_x86/vm/thread_linux_x86.cpp@899ecf76b570

src/os_cpu/linux_x86/vm/thread_linux_x86.cpp

Mercurial > jdk8-mips64-public > hotspot / file revision

src/os_cpu/linux_x86/vm/thread_linux_x86.cpp@899ecf76b570

src/os_cpu/linux_x86/vm/thread_linux_x86.cpp