On Wed, Apr 8, 2020 at 11:01 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> > > If a page is poisoned, the page->compound_head will be set to -1. > Since it has bit zero set, we will think it is a tail page, and the head > page is at 0xff..fe. Checking said head page for being poisoned will > not have good results. Therefore we need to check for poison in each > of compound_head(), PageTail() and PageCompound() (and can remove the > checks which are now redundant from the PF_ macros). > > Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Reviewed-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
