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

[Bengt Rutisson]

Hi Stefan,

On 18/02/15 10:46, Stefan Johansson wrote:
> Hi,
>
> The fix for 8062672 [1] has been pushed to 7u80 and 8u60 but the patch 
> get a small conflict when applied to 9. A bugfix only present in 9 
> changed one of the patched lines, but the conflict is easy to solve. A 
> diff between the original patch (present in 7 and 8) and the resolved 
> one shows only this diff:
> > --- a/src/os_cpu/linux_sparc/vm/vm_version_linux_sparc.cpp
> > +++ b/src/os_cpu/linux_sparc/vm/vm_version_linux_sparc.cpp
> 30c30
> < -    if (fscanf(fp, "cpu\t\t: %100[^\n]", &cpu) == 1) {
> ---
> > -    if (fscanf(fp, "cpu\t\t: %100[^\n]", cpu) == 1) {

Hm. Your forward port looks good. So, consider it reviewed by me. But 
the diff above kind of looks like a bug in the 7 and 8 branches to me.

The change from passing &cpu to pass cpu was made by this change:

JDK-8044071: Print format/argument warnings
https://bugs.openjdk.java.net/browse/JDK-8044071
http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/cb5694166a39

But this does not look like just a simple "getting rid of a warning" 
change. It looks to me like we will not detect Niagara correctly on 
Linux Sparc in JDK 7 and 8. Or am I missing something?

Bengt

>
> The full webrev is available at:
> http://cr.openjdk.java.net/~sjohanss/8062672/9/hotspot.00/
>
> The original review thread can be seen here:
> http://mail.openjdk.java.net/pipermail/hotspot-dev/2014-December/016324.html 
>
>
> Thanks,
> Stefan
>
> [1] https://bugs.openjdk.java.net/browse/JDK-8062672
>
>