[HARMONY-5617] [drlvm] On Linux crash handler may crash itself when handling SOE condition

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 5.0M6
• Component/s: DRLVM
• Environment: Linux x86 and x86_64
• Estimated Complexity: Advanced
• Assignee: Ilya Berezhniuk
• Reporter: Gregory Shimansky
• Created: 19/Mar/08 11:08
• Updated: 02/May/13 02:29

Description

When crash handler receives a SIGSEGV signal that is caused by a stack overflow, it tries to transfer control out of signal handler (just like it does for other kind of signals). But the problem is that it tries to write memory pointed to by SP register (ESP or RSP) of the original crash context. When crash happened because of stack overflow, writing to that memory may not be possible since it is protected by a guard page. In this case crash handler crashes itself:

Program terminated with signal 11, Segmentation fault.
#0 0x00002aaaaac27bbf in port_set_longjump_regs (fn=0x2aaaaac2658e, regs=0x7fffbd422b90, num=3)
at /home/gregory/work/64/trunk/working_vm/vm/port/src/thread/linux/thread_em64t.c:86
86 sp = (void)regs->rip;
(gdb) bt
#0 0x00002aaaaac27bbf in port_set_longjump_regs (fn=0x2aaaaac2658e, regs=0x7fffbd422b90, num=3)
at /home/gregory/work/64/trunk/working_vm/vm/port/src/thread/linux/thread_em64t.c:86
#1 0x00002aaaaac26579 in general_signal_handler (signum=11, info=0x7fffbd422d70,
context=0x7fffbd422c40)
at /home/gregory/work/64/trunk/working_vm/vm/port/src/signals/linux/signals_common.cpp:107
#2 <signal handler called>
#3 0x00002aaabf5254c8 in ?? ()

The crash happens for me on Gentoo Linux installations both on x86 and x86_64. The easiest way to reproduce it is to run StackTest from the smoke VM tests.

Issue Links

• is depended upon by: HARMONY-5819 [drlvm][signals] Not enough stack for SO processing in pure native threads