On Mon, Nov 15, 2021 at 10:47:01PM -0400, Harish Mara wrote: > Background: > On older kernel?s, we could have our device driver create char devices and Which device driver is this? > It looks like the culprit is zap_pte_range(), which calls > page_remove_rmap() with the compound_flag = false. As a result, instead of > decrementing the compound_mapcount for the page the page->_mapcount is > decremented causing a lot of bad page errors. There is a lot of confusion in the core MM between 'compound page' and 'PMD allocation'. I'm trying to fix it; do you have time to help?
