On Tue, 25 Feb 2014 02:45:57 -0800 "H. Peter Anvin" <h...@zytor.com> wrote:
> On 02/24/2014 10:01 PM, Chris Bainbridge wrote: > > Pentium M is PAE capable but does not indicate so in the CPUID response. > > This is an issue now that some distributions are no longer shipping > > non-PAE kernels (those distributions no longer boot on Pentium M). This > > small patch fixes the issue by forcing the PAE capability on Pentium M. > > > > For more discussion see https://bugs.launchpad.net/baltix/+bug/930447 > > > > 1. This patch doesn't match the discussion in the link. > 2. You would have to also enable this in the cpu testing code in > arch/x86/boot. > 3. At the very least we need to print a serious warning that the CPU > is being run outside its specifications. I have no personal > information about why this CPUID bit was disabled, but it could be > that it was discovered in testing that it didn't work correctly in > all circumstances (e.g. high temperature.) This is very much "use > at your own risk..."; you could get data corruption or even > hardware damage. A hang with an extended version of the no PAE message that warns you and then says "Boot with the option "forcepae" to bypass this check", would, IMHO, be a bit wiser, unless someone can actually dig out the reason it does not advertise the flag. Alan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
