Hello,
On 2018-06-04 23:10, David Holmes wrote:
Sorry to be late to this party ...
On 5/06/2018 6:10 AM, Erik Joelsson wrote:
New webrev: http://cr.openjdk.java.net/~erikj/8202384/webrev.02/
Renamed the new jvm variant to "hardened".
As it is a hardened server build I'd prefer if that were somehow
reflected in the name. Though really I don't see why this should be
restricted this way ... to be honest I don't see hardened as a variant
of server vs. client vs. zero etc at all, you should be able to harden
any of those.
I agree, and you sort of can. By adding the jvm feature
"no-speculative-cti" to any jvm variant, you get the flags. The name of
the predefined variant can be discussed. I initially suggested altserver
because I, as you, thought it should include server in the name. But
ultimately, I don't care that much about a name. There is also little
point in defining a whole set of predefined variants that nobody has
requested. If we ever need more specialized variants in the same image,
we will add them.
So IIUC with this change we will:
- always build JDK native code "hardened" (if toolchain supports it)
Yes, this is correct. The reason being that no significant performance
impact was detected, so there is no cost.
- only build hotspot "hardened" if requested; and in that case
- jvm.cfg will list -server and -hardened with server as default
Correct.
Is that right? I can see that we may choose to always build Oracle JDK
this way but it isn't clear to me that its suitable for OpenJDK. Nor
why hotspot is selectable but JDK is not. ??
We would prefer to always build with security features enabled, but the
performance impact on the JVM is so high that we want to leave it to the
user to decide, both at bulid time and at runtime. With these changes,
Oracle will build OracleJDK, and OpenJDK, with dual JVMs by default, but
any other person or entity just building the OpenJDK source will just
get the server variant for now (as has been the default for a long
time), unless they specifically ask for "hardened" or activate the new
jvm feature (--with-jvm-feature=no-speculative-cti).
We don't see the point in giving the choice on the JDK libraries simply
because there is no drawback to enabling the flags.
/Erik
Sorry.
David
-----
/Erik
On 2018-06-04 09:54, jesper.wilhelms...@oracle.com wrote:
On 4 Jun 2018, at 17:52, Erik Joelsson <erik.joels...@oracle.com>
wrote:
Hello,
On 2018-06-01 14:00, Aleksey Shipilev wrote:
On 06/01/2018 10:53 PM, Erik Joelsson wrote:
This patch defines flags for disabling speculative execution for
GCC and Visual Studio and applies
them to all binaries except libjvm when available in the
compiler. It defines a new jvm feature
no-speculative-cti, which is used to control whether to use the
flags for libjvm. It also defines a
new jvm variant "altserver" which is the same as server, but with
this new feature added.
I think the classic name for such product configuration is
"hardened", no?
I don't know. I'm open to suggestions on naming.
"hardened" sounds good to me.
The change looks good as well.
/Jesper
/Erik
-Aleksey
