On Wed, Apr 04, 2007 at 02:27:01PM +0200, Andrea Arcangeli wrote: > On Wed, Apr 04, 2007 at 12:24:07PM +0200, Nick Piggin wrote: > > But for a potential mainline merge, maybe starting with a CONFIG > > option is a good idea -- defaulting to off, and we could start by > > turning it on just in -rc kernels for a few releases, to get a bit > > more confidence? > > The only reason to do that is if there are many stupid apps pretending > to get meaningful information from pages that cannot contain any > information. The zero page in the anon page fault has been there > forever so...
There might be a lot of applications like that, and I'm not sure that _all_ of them can be considered 'stupid' as you say. How about applications that perform mmap() and R/W random-access on large *sparse* files? (e.g. a scientific app that uses a large sparse file as a big database look-up table). As I see it, these apps would need to keep track of what's sparse and what's not... -- Dan Aloni XIV LTD, http://www.xivstorage.com da-x (at) monatomic.org, dan (at) xiv.co.il - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
