On Sun, Oct 23, 2011 at 12:23:47PM -0700, Keith Packard wrote: > On Sun, 23 Oct 2011 12:18:30 +0200, Daniel Vetter <[email protected]> wrote: > > Hi Keith, > > > > This patch isn't in your -next pull. This papers over a spurious -EFAULT > > in the pwrite/pread paths that actually gets hit in the wild. The real fix > > in the form of a almost complete rewrite of the pwrite/pread paths won't > > be ready for 3.2. > > We had several comments wondering whether writing zeros was OK as this > occurs before some potential error returns that should leave the buffer > unmodified. I didn't have a better suggestion, but that seems pretty > sketchy to me.
This patch only fixes things up so that we prefault the entire page range and not just the first PAGE_SIZE bytes (i.e. at most 2 pages). So I don't see the risk of extending the current behaviour to all pages. Userspace can already see these zero writes, but only when doing something stupid. -Daniel -- Daniel Vetter Mail: [email protected] Mobile: +41 (0)79 365 57 48 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
