A few things: I verified that this problem does not recreate on buster, as Ryan mentioned earlier, because of the disabling of lock elision in glibc. I verified that this problem still exists on a Debian 9.8 base with upstream kernel 5.1.0-x, which contains up-to-date TM fixes. Our kernel team is actively debugging this problem on upstream kernel 5.2.0-rc5, and is in favor of disabling TM in Debian until this issue is resolved. Thanks. Barry
