On Mar 19, 2013, at 5:21 PM, John Rose <john.r.r...@oracle.com> wrote:
> On Mar 14, 2013, at 8:31 PM, Christian Thalinger > <christian.thalin...@oracle.com> wrote: > >> [This is the HotSpot part of JEP 176] >> >> http://cr.openjdk.java.net/~twisti/7198429 >> >> 7198429: need checked categorization of caller-sensitive methods in the JDK >> Reviewed-by: > > > Over all, great work on a tricky problem. I'd add a few asserts and tweak a > couple of lines; see below. Reviewed as is or with suggested changes. — John > > --- Method::is_ignored_by_security_stack_walk > I would like to see reflect_invoke_cache go away some day. Would it be > possible to strengthen the asserts to prove that it is an expensive alias for > an intrinsic_id check? (I realize this is a question mainly for folks > working on JVMTI.) That's what I tried to do: if the intrinsic_id == _invoke it also must be the same method in reflect_invoke_cache. More than that would mean to enhance ActiveMethodOopsCache because you can't ask for methods in the cache. > > --- JVM_GetCallerClass > Suggest an assert for vfst.method() == NULL. Should not happen, and previous > code would apparently have crashed already, but... > > (The corner case I'm thinking of is a compiled frame with nmethod::method > returning null after nmethod::make_unloaded. Should not happen.) Sure, I can add that assert but there is other code in jvm.cpp that relies on the fact that vfst.method() is non-null. We should add asserts in all that places but that's for another RFE. > > --- JVM_GetClassContext > What do these lines do: > + // Collect method holders > + GrowableArray<KlassHandle>* klass_array = new > GrowableArray<KlassHandle>(); > > It looks like a paste-o from another source base. Left over. I filed an RFE for that improvement: JDK-8010124: JVM_GetClassContext: use GrowableArray instead of KlassLink > > --- LibraryCallKit::inline_native_Reflection_getCallerClass > > I believe this assertion, but I would prefer to see it checked more forcibly: > + // NOTE: Start the loop at depth 1 because the current JVM state does > + // not include the Reflection.getCallerClass() frame. > > Not sure there is a good way to do this. But, perhaps put the comment here: > case 0: > // ...comment... > ShouldNotReachHere(); How about: case 0: fatal("current JVM state does not include the Reflection.getCallerClass() frame"); break; > > Also, if something goes wrong with caller sensitivity, we just get a "return > false". Perhaps do a "caller_jvm=NULL;break" to branch to the pretty failure > message? That makes it slightly easier to see what happened. It seems easier to add printing code to the case statement: case 1: // Frame 0 and 1 must be caller sensitive (see JVM_GetCallerClass). if (!m->caller_sensitive()) { #ifndef PRODUCT if ((PrintIntrinsics || PrintInlining || PrintOptoInlining) && Verbose) { tty->print_cr(" Bailing out: CallerSensitive annotation expected at frame %d", n); } #endif return false; // bail-out; let JVM_GetCallerClass do the work } break; > > The LogCompilation switch should leave a "paper trail". Actually, I see that > LogCompilation doesn't mention failed intrinsic inlines. Rats. At least > PrintInlining or PrintIntrinsics (diagnostic flags) will give us some > leverage if we need to debug. > > --- JVM_RegisterUnsafeMethods > That's an improvement. Thanks. > > (A nagging worry: How big are those static tables getting?) We could remove some very old ones like 1.4.0 and 1.4.1. This time, next time? > > --- vframeStreamCommon::security_get_caller_frame > This now does something odd if depth < 0. Suggest an assert. The behavior with depth < 0 in the current code is even worse. An assert is a good idea. As discussed I want to remove that method in the future because its uses are dubious. -- Chris
