On 11/16/22 02:25, Vlastimil Babka wrote: >> Referring back to your thoughts about putting these pages on some leaked >> pages list, do any such leaked pages list exist currently ? > Not AFAIK, you could just create a list_head somewhere appropriate (some snp > state structure?) and put the pages there, maybe with a counter exposed in > debugs. The point would be mostly that if something goes so wrong it would > be leaking substantial amounts of memory, we can at least recognize the > cause (but I suppose the dmesg will be also full of messages) and e.g. find > the pages in a crash dump. It might also be worth looking through the places that check PageHWPoison() and making sure that none of them are poking into the page contents. It's also the kind of thing that adding some CONFIG_DEBUG_VM checks might help with. For instance, nobody should ever be kmap*()'ing a private page. The same might even go for pin_user_pages().
