Dne 12.5.2011 04:12, Linus Torvalds napsal(a): > On Wed, May 11, 2011 at 1:42 AM, Milan Broz <mbroz@xxxxxxxxxx> wrote: >> >> Another one is cryptsetup [..] > > Quite frankly, all security-related uses should always be happy about > a "MCL_SPARSE" model, since there is no point in ever bringing in > pages that haven't been used. The whole (and only) point of > mlock[all]() for them is the "avoid to push to disk" issue. > > I do wonder if we really should ever do the page-in at all. We might > simply be better off always just saying "we'll lock pages you've > touched, that's it". > For LVM we need to ensure the code which might ever be executed during disk suspend state must be paged and locked in - thus we would need MCL_SPARSE only on several selected 'unneeded' libraries - as we are obviously not really able to select which part of glibc might be needed during all code path (though I guess we may find some limits). But if we are sure that some libraries and locale files will never be used during suspend state - we do not care about those pages at all. So it's not like we would always need only MCL_SPARSE all the time - we would probably need to have some control to switch i.e. glibc into MCL_ALL. Zdenek -- 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
