-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 12/02/2014 04:09 AM, Shachar Raindel wrote: >> I believe the mmu_notifier_invalidate_range_start & _end >> functions can be moved inside the pte_same(*page_table, >> orig_pte) branch. There is no reason to call those functions if >> we do not modify the page table entry. >> > > There is a critical reason for this - moving the MMU notifiers > there will make them unsleepable. This will prevent hardware > devices that keep secondary PTEs from waiting for an interrupt to > signal that the invalidation was completed. This is required for > example by the ODP patch set > (http://www.spinics.net/lists/linux-rdma/msg22044.html ) and by the > HMM patch set > (http://comments.gmane.org/gmane.linux.kernel.mm/116584 ). Ahhhh, that explains! Acked-by: Rik van Riel <riel@xxxxxxxxxx> - -- All rights reversed -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJUfdMnAAoJEM553pKExN6D6HQH/jYio5UBhlPhjp9XjWxwrDHy 7Pcf9nATYQhSN5IuxWp265yHMbFu9CwJefW2DLZLXbynImiy8rkl0HkaaDXEZnM4 ZizjCcxjgNVxD+F+EAsi/bj6kCtxNfmM0YxLCNHjOp835JQzQTbx94Joy1B10ba+ 42sTbGBArBVVuDOfHpiUMCj8HFiRT2BNwpfu44eDLAJQiTZIYU5OlXmWnSJQXDDF c648arGq75fyA8RHRZ/cTf0pztT+Gx5q/2LAxy+MkhiZjX9kXc1e98gWTOO70Qj+ IwP4YAfgScts+uqL2Q+EUVo0nBYAT1amyZft6j3aLQRrDcFhCkITk2VW0CdZHdE= =IA5v -----END PGP SIGNATURE----- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>