On Tue, May 1, 2018 at 7:53 PM, Linus Torvalds <torva...@linux-foundation.org> wrote: > On Tue, May 1, 2018 at 7:26 PM Dan Williams <dan.j.willi...@intel.com> > wrote: > >> Right, but the only way to make MCE non-fatal is to teach the machine >> check handler about recoverable conditions. This patch teaches the >> machine check handler how to recover copy_to_iter() errors. > > Why not just unmap the page and remap a new page in its place? Meaning > that it needs absolutely no special error handling in the callers. > > IOW, treat it *exactly* like the whole page poisoning. > > We _have_ the technology. Why does this code think it's such a special > snow-flake?
Because dax. There's no page cache indirection games we can play here to poison a page and map in another page. The mapped page is 1:1 associated with the filesystem block and physical memory address.
