Re: [BUG] x86 kenel won't boot under Virtual PC

From: H. Peter Anvin
Date: Mon Sep 08 2008 - 11:50:53 EST


H. Peter Anvin wrote:

The help text is indeed out of date. I did a patch yesterday to, among other things, update it; I also want to verify that we are disabling all options that can cause gcc or binutils to generate nopl's; I plan to push it today.


OK, turns out that is already happending, by virtue of:

# add at the end to overwrite eventual tuning options from earlier
# cpu entries
cflags-$(CONFIG_X86_GENERIC) += $(call tune,generic,$(call tune,i686))

-mtune=generic on 32-bit CPUs disable NOPL generation, and any gcc/binutils combo too old to have -mtune=generic won't generate them at all.

I think I verified this some time in the past, but I just had to refresh my memory. This was a major reason to put this functionality on CONFIG_X86_GENERIC.

-hpa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/