On Thu, Nov 4, 2021 at 11:39 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > On Thu, Nov 04, 2021 at 08:30:55AM -0700, Linus Torvalds wrote: > > Why did this come up? Do you actually have some hardware or situation > > that cares? > > Oh, we're doing review of the XFS/iomap folio patches, which led to > looking at zero_user_segments(), and I realised that memzero_page() > was now functionally identical to zero_user(). And you'd been quite > specific about not having flush_dcache_page() in there, so ... I wondered > if you'd had a change of mind. Ugh. I guess it ends up being there whether I like it or not. All that "zero_user_segments() stuff is too ugly for words, though, so I think whoever wrote it must have been on some interesting pharmaceuticals. What the hell are the two start/end things? And most users actually just want a single page and should never have used that thing. Nasty. I'm not touching that with a ten-foot pole. Linus