* Dave Jones <[EMAIL PROTECTED]> wrote: > > you mean modifies MTRRs? Which code is that? (besides the > > /proc/mtrr userspace API) > > This exclusion is going to be a real pain in the ass for distro > kernels. It's impossible for example to build a kernel that will now > support the MTRR-alike registers on the AMD K6/early Cyrix etc and > also support PAT. > > Additionally, given people tend to update their kernels a lot more > often than they update to a whole new version of X, it means until > userspace has caught up, we can't ship a kernel with PAT supported, or > else X gets a lot slower due to the missing mtrr support.
there's no exclusion enforced right now, and if a CPU is PAT-incapable (or if the kernel is booted nopat) then the MTRR bits should be usable. But if we boot with PAT enabled, and Xorg gets /proc/mtrr wrong, we'll see nasty crashes. If it gets them right, it should all still work just fine. Is this ok? Then, in a year or two, distros can disable write support to /proc/mtrr. Hm? Ingo -- 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/