On Wed, 2014-01-22 at 15:39 -0500, Mikulas Patocka wrote: > > On Wed, 22 Jan 2014, James Bottomley wrote: > > > On Wed, 2014-01-22 at 14:11 -0500, Mikulas Patocka wrote: > > [no comment on the merits of the patch, just the wording of the change > > log] > > > This patch changes it so that INEQUIVALENT ALIASES are only reported for > > > writeable mappings. PA-RISC specification allows inequivalent aliases for > > > read-only mappings, so there's no need to report them as an error. > > > > No, it doesn't. The spec says no inequivalent aliases at all for > > certain types of CPU (that was the cause of the inability to boot on the > > CPU with the combined PIPT/VIPT cache) ... we believe we skirted the > > requirements with some judicious flushing but we can't say it was > > supported by the docs. > > > > James > > A citation from Parisc 2.0 specification, Appendix F, section Address > Aliasing: > > "Software is allowed to have any number of read-only non-equivalently > aliased translations to a physical page, as long as there are no other > translations to the page. This is referred to as read-only non-equivalent > aliasing." The kernel alias is read/write. James -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
