In my preceding response, I said that I saw no reason why a constrained transaction could not cross a cache-line boundary ... which did not fully answer Mr. Dravniek's question about whether it could cross a page boundary.
As long as both pages are accessible, then the answer should be the same: no problemo. If the second page is valid but paged out, the transaction will abort due to the translation exception, the O/S will eventually page in the second page, and the transaction will be redriven from the TBEGINC.
