------- Comment From geral...@de.ibm.com 2017-09-20 08:56 EDT------- It doesn't look like "brk_near_huge" is hanging, but rather the next test "task-size-overrun". The Assertion failure originates from "brk_near_huge", but that is probably unrelated to the hanging "task-size-overrun".
Also, "task-size-overrun" may only appear to be hanging, IIRC this test will try to figure out the TASK_SIZE by successively allocating 4K pages as long as possible. We already had an issue there on s390, with our dynamic pagetable upgrade feature, which was fixed by the following libhugetlbfs commit: commit a06eeed7e005af579169f3020d3980198eb3ba30 Author: Gerald Schaefer <gerald.schae...@de.ibm.com> Date: Thu Mar 7 15:41:58 2013 +0100 task-size-overrun: fix problem with dynamic pagetable upgrade on s390x The strategy to find out TASK_SIZE won't work on s390x anymore, starting with kernel 3.9. We will dynamically increase the pagetable levels on s390x on access beyond TASK_SIZE, effectively increasing TASK_SIZE from 2^42 to 2^53, but /proc/self/maps won't reflect this. With the current strategy that means that find_task_size() would loop for a very long time, from 2^42 to 2^53. To fix this, increase addr in the loop for s390x as soon as we exceed the 2^42 limit. Signed-off-by: Gerald Schaefer <gerald.schae...@de.ibm.com> Signed-off-by: Eric B Munson <emun...@mgebm.net> Since we only recently added 5-level pagetable support, I guess this fix no longer helps, as we will now loop from 2^53 to 2^64. I'll look into this, we probably need to update "task-size-overrun" again to reflect the 5-level pagetable update. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1718107 Title: brk_near_huge test will hang on IBM s390x zKVM / zVM To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1718107/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs