Messages in this thread | | | Date | Tue, 10 Jun 2008 14:06:37 +0100 | From | Jeremy Fitzhardinge <> | Subject | Re: [PATCH UPDATED] x86: set PAE PHYSICAL_MASK_SHIFT to 44 bits. |
| |
Ingo Molnar wrote: >> When a 64-bit x86 processor runs in 32-bit PAE mode, a pte can >> potentially have the same number of physical address bits as the >> 64-bit host ("Enhanced Legacy PAE Paging"). This means, in theory, we >> could have up to 52 bits of physical address in a pte. >> >> The 32-bit kernel uses a 32-bit unsigned long to represent a pfn. This >> means that it can only represent physical addresses up to 32+12=44 >> bits wide. Rather than widening pfns everywhere, just set 2^44 as the >> Linux x86_32-PAE architectural limit for physical address size. >> > > applied to tip/x86/cleanups - thanks Jeremy. No urgency for v2.6.26, > right?
Not urgent, but it would be nice to have.
J
| |