Can't get hs_err log on native stack overflow on Linux

[Yasumasa Suenaga]

Hi, David,
Thank you for replying.

(2011/08/09 15:51), David Holmes wrote:
> Hi,
> 
> I could be mistaken here but I believe the intent/hope is that any
> stackoverflow will be caught when the guard pages set up by the VM are
> accessed. In that way we haven't run out of true native stack and so we
> can still process the signal that indicates the stack overflow. This is
> not a perfect mechanism of course and there may be situations where you
> can jump over the guard pages and truly exhaust the stack.

Yes, I agree.

> I also believe there is a bit of bad history here, where we had problems
> trying to use alternative signal stacks on Linux. It will take me a bit
> of archaeology to dig up relevant info on that.

If you've dug up relevant info, please tell me.


BTW, my patch provides new VM option "UseAlternateSignalStack" .
If this option sets to false, this patch (sigaltstack) will not work.

When it is a viewpoint of the troubleshooting, I want to this function.
If I can get hs_err log at native stack overflow, I can certainly suggest
expanding stack area (-Xss).

Thanks,

Yasumasa

> David Holmes
> 
> Yasumasa Suenaga said the following on 08/09/11 16:06:
>> Hi,
>>
>> I encountered native stack overflow at JNI code on Linux (Fedora 15 and Ubuntu 11).
>> I got coredump image, however, I could not get hs_err log.
>>
>> In the case of SIGSEGV, hs_err log is generated in signal handler. If native
>> stack overflow occurred, Linux can't use stack area. So, SIGSEGV handler
>> (JVM_handle_linux_signal) is never called.
>>
>> manpage of sigaltstack(2):
>> /****************/
>> NOTES
>>         The most common usage of an alternate signal stack is to handle the SIGSEGV sig‐
>>         nal that is generated if the space available for the  normal  process  stack  is
>>         exhausted:  in  this case, a signal handler for SIGSEGV cannot be invoked on the
>>         process stack; if we wish to handle it, we must use an alternate signal stack.
>> /****************/
>>
>>
>> If this patch is applied, we can get hs_err log on native stack overflow as follows:
>>
>> /****************/
>> #
>> #  SIGSEGV (0xb) at pc=0x00007fb23f1265f7, pid=25748, tid=140403650643712
>> #  java.lang.StackOverflowError: Native stack
>> #
>> # JRE version: 8.0
>> # Java VM: OpenJDK 64-Bit Server VM (22.0-b01 mixed mode linux-amd64 compressed oops)
>> # Problematic frame:
>> # C  [liboverflow.so+0x5f7]  Java_Main_doStackOverflow+0x3b
>> /****************/
>>
>>
>> I've attached this patch and testcase in this email. Please check it.
>>
>>
>> I would like to contribute this patch, and I hope to apply this patch to
>> JDK 6 / 7 / 8.
>>
>>
>> Please cooperate.
>>
>> Best regards,
>> Yasumasa
>>