Messages in this thread | | | Subject | Re: Subject: [PATCH 1/2] x86: get back 15 vectors | From | Suresh Siddha <> | Date | Mon, 04 Jan 2010 16:05:44 -0800 |
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On Mon, 2010-01-04 at 11:50 -0800, H. Peter Anvin wrote: > On 01/04/2010 11:45 AM, Suresh Siddha wrote: > > On Mon, 2010-01-04 at 11:35 -0800, Yinghai Lu wrote: > >> sth like this? > >> > >> Subject: [PATCH 1/2] x86: get back 16 vectors > >> > >> -v2: according to hpa that we could start from 0x10 > >> according to Eric, we should hold 16 vectors for IRQ MOVE > >> > >> Signed-off-by: Yinghai Lu <yinghai@kernel.org> > >> > > > > Yinghai we have to change IRQ_MOVE_CLEANUP_VECTOR to 0x1f or so. From > > the cpu perspective this vector is documented as illegal, so we need to > > check if this change will work on the cpu's we have today to get some > > confidence. > > > > It's documented as reserved, not illegal. The ability for the APIC to > generate vectors starting at 0x10 is documented, as is the ability for > the CPU to receive any vector number as an interrupt -- in fact, the > legacy BIOS relies on being able to receive interrupts starting at > vector 0x08. It causes problems galore, but only at the software level.
I have checked out couple of platforms (including 32-bit atom) and 0x1f vector logic seems to be working.
Hopefully we won't have other hardware or software issues (vmm restrictions etc) with this logic.
thanks, suresh
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