From: Linus Torvalds <[EMAIL PROTECTED]> Date: Thu, 28 Dec 2006 12:14:31 -0800 (PST)
> I get corruption - but the whole point is that it's very much pdflush that > should be writing these pages out. I think what might be happening is that pdflush writes them out fine, however we don't trap writes by the application _during_ that writeout. These corruptions look exactly as if: 1) pdflush begins writeback of page X 2) page goes to disk 3) application writes a chunk to the page 4) pdflush et al. think the page is clean, so it gets tossed, losing the writes done in #3 So there's a missing PTE change in there, so that we never get proper re-dirtying of the page if the application tries to write to the page during the writeback. It's something that will only occur with writeback and MAP_SHARED writable access to the file pages. That's why we never see this with normal filesystem writes, since those explicitly manage the page dirty state. I think the dirty balancing logic etc. isn't where the problems are, to me it's a PTE state update issue for sure. - 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/
