On Fri, Jul 26, 2013 at 01:19:30PM -0700, H. Peter Anvin wrote: > Hi everyone, > > I have tagged this one for -stable, but it is a definite "maybe", so I > wanted to: > > a) qualify that tagging, and > b) perhaps use it as a boundary case for policy clarification. > > This patch is an old bug, an incorrect assembly constraint, but as > happens with this type of bug it is being exposed by a change in gcc. > Therefore, although this is neither a regression per se in the kernel > nor in gcc, it is a regression in the combined output. > > The bug is obvious; the fix at the very least *should* be obvious; the > main source of risk would appear that it might trigger bugs in very old > versions of gcc. > > The gain is less inherently obvious: currently the only MXCSR bit > affected is DAZ, although this also affects any future MXCSR bits. Most > users do not care about DAZ, but the ones that do generally care *a lot* > about it as their applications may suffer very bad performance otherwise. > > There is a kernel bugzilla for this: > > https://bugzilla.kernel.org/show_bug.cgi?id=60633 > > ... but it doesn't really add any additional information. Thanks for the additional information, it's much appreciated. greg k-h -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html