linux/arch
venkatesh.pallipadi@intel.com 3869c4aa18 x86, PAT: Changing memtype to WC ensuring no WB alias
As per SDM, there should not be any aliasing of a WC with any cacheable
type across CPUs. That is if one CPU is changing the identity map
memtype to _WC, no other CPU at the time of this change should not have a
TLB for this page that carries a WB attribute. SDM suggests to make the
page not present. But for that we will have to handle any page faults
that can potentially happen due to these pages being not present.

Other way to deal with this without having any WB mapping is to change
the page first to UC and then to WC. This ensures that we meet the SDM
requirement of no cacheable alais to WC page. This also has same or
lower overhead than marking the page not present and making it present
later.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20090409212708.797481000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-10 13:55:47 +02:00
..
alpha Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
arm Merge branch 'i2c-for-2630-v2' of git://aeryn.fluff.org.uk/bjdooks/linux 2009-04-07 08:45:12 -07:00
avr32 dma-mapping: replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32) 2009-04-07 08:31:11 -07:00
blackfin tty: Blackin CTS/RTS 2009-04-07 08:44:05 -07:00
cris tty: Use the generic RS485 ioctl on CRIS 2009-04-07 08:44:05 -07:00
frv FRV: Fix compile breakage 2009-04-06 14:31:26 -07:00
h8300 Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
ia64 dma-mapping: replace all DMA_24BIT_MASK macro with DMA_BIT_MASK(24) 2009-04-07 08:31:12 -07:00
m32r Simplify copy_thread() 2009-04-02 19:04:51 -07:00
m68k Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
m68knommu Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2009-04-03 09:44:58 -07:00
mips dma-mapping: replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32) 2009-04-07 08:31:11 -07:00
mn10300 Simplify copy_thread() 2009-04-02 19:04:51 -07:00
parisc Merge git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6 2009-04-03 09:52:04 -07:00
powerpc Merge branch 'i2c-for-2630-v2' of git://aeryn.fluff.org.uk/bjdooks/linux 2009-04-07 08:45:12 -07:00
s390 Merge branch 'ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-03 17:33:30 -07:00
sh Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6 2009-04-05 11:15:54 -07:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask 2009-04-05 10:33:07 -07:00
um Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
x86 x86, PAT: Changing memtype to WC ensuring no WB alias 2009-04-10 13:55:47 +02:00
xtensa Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
.gitignore
Kconfig Merge branch 'tracing/core-v2' into tracing-for-linus 2009-04-02 00:49:02 +02:00