Messages in this thread | | | Date | Wed, 19 Dec 2012 08:05:38 -0800 | Subject | Re: Why Linux kernel forced to enter X2APIC mode( just because of booting cpu has supported x2apic) without depending on BIOS' setting in MSR->x2apic enablement bit ? | From | Yinghai Lu <> |
| |
On Wed, Dec 19, 2012 at 2:36 AM, Zhang, Lin-Bao (Linux Kernel R&D) <linbao.zhang@hp.com> wrote: > Hi Yinghai , > > Actually ,my question like this: > OS can really enable x2apic correctly without BIOS' help in this case : > BIOS has claimed definitely it doesn't enable x2apic ,but OS feel it can enable x2apic(based on BSP supports x2apic) ).
how does BIOS cleaim?
disable that in CPUID?
> > If Linux don't need BIOS' help , how did linux kernel reach this action?
need DMAR table to enable intr remapping. --- ioapic only have 8 bits for dst.
| |