Need reviewers for changes in JVM initialization code (added check for -XX:StackShadowPages option)

[David Holmes]

Responding to Tom's query ...

> Tom Rodriguez said the following on 07/28/10 04:49:
>> I think you could put this check into arguments.cpp since I all 
>> platforms would require a positive number for the StackShadowPages.  
>> The same should be true of StackRedPages and StackYellowPages.  
>> Actually they all should be required to greater than 0 I think.  Other 
>> than that I don't see other obvious constraints on the values.  That 
>> bug report doesn't really show other problematic values, though I'm 
>> not sure I follow the point of the guarantee that's failing either.  
>> What does the min stack size have to do with the number of guard 
>> pages?  I would expect it to be checking against ThreadStackSize and 
>> returning an error if it was too small like the other places that 
>> check against TheadStackSize.

It's a simple sanity check that the minimum allowed stack size can 
actually accommodate a stack with all the requested guard pages. We need 
a minimum allowed, as well as a default (ThreadStackSize) for when 
stacks are programmatically requested.

David

>>
>> tom
>>
>> On Jul 27, 2010, at 8:15 AM, Pavel Tisnovsky wrote:
>>
>>> Hi all,
>>>
>>> can anybody please review two quite simple changes in JVM 
>>> initialization code? Webrev is available at:
>>> http://cr.openjdk.java.net/~ptisnovs/StackShadowPagesCheck/
>>>
>>> When -XX:StackShadowPages is set to negative integer or zero value, 
>>> JVM segfaulted on Linux and, according to 
>>> http://bugs.sun.com/view_bug.do?bug_id=6885308, hangs up on Solaris 
>>> (although I only check this issue on Linux)
>>>
>>> I also would like to add more check for -XX:StackRedPages, 
>>> -XX:StackShadowPages and -XX:StackYellowPages options to avoid issue 
>>> described in the bug report mentioned above 
>>> (http://bugs.sun.com/view_bug.do?bug_id=6885308) but I'm unable to 
>>> find relevant information about proper conditions (it may depends on 
>>> page sizes, VM stack size etc.). Any ideas?
>>>
>>> Cheers
>>> Pavel Tisnovsky
>>>
>>