Messages in this thread | | | Subject | Re: x2apic boot failure on recent sandy bridge system | From | Suresh Siddha <> | Date | Fri, 19 Oct 2012 16:03:58 -0700 |
| |
On Fri, 2012-10-19 at 13:42 -0700, rrl125@gmail.com wrote: > Any update? The messages just seem to have stopped months ago. A > fallback would be nice, I have been booting the kernel with noa2xpic > for since kernel 3.2, and currently I am working with 3.6.2. > > If needed I can try to attempt modifying the patch to include > fallback, but I am probably not the best person to do it. >
Are you referring to this commit that made into the mainline tree already?
commit fb209bd891645bb87b9618b724f0b4928e0df3de Author: Yinghai Lu <yinghai@kernel.org> Date: Wed Dec 21 17:45:17 2011 -0800
x86, x2apic: Fallback to xapic when BIOS doesn't setup interrupt-remapping
On some of the recent Intel SNB platforms, by default bios is pre-enabling x2apic mode in the cpu with out setting up interrupt-remapping. This case was resulting in the kernel to panic as the cpu is already in x2apic mode but the OS was not able to enable interrupt-remapping (which is a pre-req for using x2apic capability).
On these platforms all the apic-ids are < 255 and the kernel can fallback to xapic mode if the bios has not enabled interrupt-remapping (which is mostly the case if the bios has not exported interrupt-remapping tables to the OS).
Reported-by: Berck E. Nash <flyboy@gmail.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/20111222014632.600418637@sbsiddha-desk.sc.intel.com Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| |