RFR: 8062672: JVM crashes during GC on various asserts which checks that HeapWord ptr is an oop

[Jon Masamitsu]

Stefan,

Changes look good.

Would you like to explicitly check the return from
fgets() against NULL?  Your call.

What do you think of an assert after the call to fgets() to
check the length of the returned string.

assert(strnlen(line, 1023) < 1023, "buffer line[1024] is too small.");

Too paranoid?

Reviewed.

Jon

On 12/5/2014 2:01 AM, Stefan Johansson wrote:
> Hi,
>
> Please review this fix for the linux-sparc issue described in:
> https://bugs.openjdk.java.net/browse/JDK-8062672
>
> Webrev:
> http://cr.openjdk.java.net/~sjohanss/8062672/hotspot.00/
>
> Summary:
> This fix is based on 7u-dev because the most linux-sparc testing is 
> done for that release and also because it's unclear if we have time to 
> move the fix the normal way through 9 and 8u before going into 7u. But 
> the main reason is that it would be good to get testing of the fix in 
> 7u before porting it to 8u and 9.
>
> The fix it self is fairly simple, after JDK-8029190 was backported the 
> condition for disabling UseMemSetInBOT changed from is_niagara() to 
> has_blk_init(). This worked well for solaris-sparc but on linux-sparc 
> we previously only set the niagara feature bits, so this change adds 
> support for detecting blk_init support on linux-sparc.
>
> Testing:
> Crashes/asserts was reproducible without the fix and after the fix 
> none have been observed. Also verified that UseMemSetInBOT now is set 
> to false as it should be.
>
> Thanks,
> Stefan