Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-15 Thread David Holmes
Hi Jamsheed, On 16/07/2020 8:16 am, Jamsheed C M wrote: (Thank you Dean, adding serviceability team as this issue involves JVMTI features PopFrame, EarlyReturn features) It is not at all obvious how your proposed fix impacts the JVM TI features. JBS entry: https://bugs.openjdk.java.net/brows

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-15 Thread David Holmes
Hi Jamsheed, tl;dr version: fix looks good. Thanks for working through things with me on this one. Long version ... for the sake of other reviewers (and myself) I'm going to walk through the problem scenario and how the fix addresses it, because the bug report is long and confusing and touch

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-15 Thread Jamsheed C M
Hi David, On 16/07/2020 05:20, David Holmes wrote: Hi, Async handling at method entry requires it to be aware of synchronization(like whether it is doing async handling before lock acquire or after) This is required as exception handler rely on this info for unlocking.  Async handling cod

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-15 Thread Jamsheed C M
(Thank you Dean, adding serviceability team as this issue involves JVMTI features PopFrame, EarlyReturn features) JBS entry: https://bugs.openjdk.java.net/browse/JDK-8246381 (testing: mach5, tier1-5 links in JBS) Best regards, Jamsheed On 15/07/2020 21:25, Jamsheed C M wrote: Hi, Async ha

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-15 Thread Jamsheed C M
Hi David, On 16/07/2020 05:20, David Holmes wrote: Hi Jamsheed, On 16/07/2020 8:16 am, Jamsheed C M wrote: (Thank you Dean, adding serviceability team as this issue involves JVMTI features PopFrame, EarlyReturn features) It is not at all obvious how your proposed fix impacts the JVM TI feat

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-15 Thread Jamsheed C M
Hi David, On 16/07/2020 06:37, David Holmes wrote: Hi Jamsheed, tl;dr version: fix looks good. Thanks for working through things with me on this one. Long version ... for the sake of other reviewers (and myself) I'm going to walk through the problem scenario and how the fix addresses it, b

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-16 Thread Jamsheed C M
Hi all, could i get another review? Best regards, Jamsheed On 16/07/2020 06:37, David Holmes wrote: Hi Jamsheed, tl;dr version: fix looks good. Thanks for working through things with me on this one. Long version ... for the sake of other reviewers (and myself) I'm going to walk through t

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-16 Thread coleen . phillimore
Thanks to David's description of the problem and the fix, this makes sense to me now. I don't like it and we should revisit async exceptions for all the other problems it causes, but this change looks safe and good. thanks, Coleen On 7/16/20 3:00 AM, Jamsheed C M wrote: Hi all, could i ge

Re: [15] RFR: 8246381: VM crashes with "Current BasicObjectLock* below than low_mark"

2020-07-16 Thread Jamsheed C M
Hi Coleen, Thank you for the review. Best regards, Jamsheed On 16/07/2020 20:13, coleen.phillim...@oracle.com wrote: Thanks to David's description of the problem and the fix, this makes sense to me now. I don't like it and we should revisit async exceptions for all the other problems it ca