This patch reverts NUMA affine page table allocation added by commit
1411e0ec (x86-64, numa: Put pgtable to local node memory).

The commit made an undocumented change where the kernel linear mapping
strictly follows intersection of e820 memory map and NUMA
configuration.  If the physical memory configuration has holes or NUMA
nodes are not properly aligned, this leads to using unnecessarily
smaller mapping size which leads to increased TLB pressure.  For
details,

  http://thread.gmane.org/gmane.linux.kernel/1104672

Patches to fix the problem have been proposed but the underlying code
needs more cleanup and the approach itself seems a bit heavy handed
and it has been determined to revert the feature for now and come back
to it in the next developement cycle.

  http://thread.gmane.org/gmane.linux.kernel/1105959

As init_memory_mapping_high() callsites have been consolidated since
the commit, reverting is done manually.  Also, the RED-PEN comment in
arch/x86/mm/init.c is not restored as the problem no longer exists
with memblock based top-down early memory allocation.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>

e820_table_{start|end|top}, which are used to buffer page table
allocation during early boot, are now derived from memblock and don't
have much to do with e820.  Change the names so that they reflect what
they're used for.

This patch doesn't introduce any behavior change.

-v2: Ingo found that earlier patch "x86: Use early pre-allocated page
     table buffer top-down" caused crash on 32bit and needed to be
     dropped.  This patch was updated to reflect the change.

-tj: Updated commit description.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

There's no reason for these to live in setup_arch().  Move them inside
initmem_init().

- v2: x86-32 initmem_init() weren't updated breaking 32bit builds.
  Fixed.  Found by Ankita.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ankita Garg <ankita@in.ibm.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

initmem_init() extensively accesses and modifies global data
structures and the parameters aren't even followed depending on which
path is being used.  Drop @start/last_pfn and let it deal with
@max_pfn directly.  This is in preparation for further NUMA init
cleanups.

- v2: x86-32 initmem_init() weren't updated breaking 32bit builds.
  Fixed.  Found by Yinghai.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Introduce init_memory_mapping_high(), and use it with 64bit.

It will go with every memory segment above 4g to create page table to the
memory range itself.

before this patch all page tables was on one node.

with this patch, one RED-PEN is killed

debug out for 8 sockets system after patch
[    0.000000] initial memory mapped : 0 - 20000000
[    0.000000] init_memory_mapping: [0x00000000000000-0x0000007f74ffff]
[    0.000000]  0000000000 - 007f600000 page 2M
[    0.000000]  007f600000 - 007f750000 page 4k
[    0.000000] kernel direct mapping tables up to 7f750000 @ [0x7f74c000-0x7f74ffff]
[    0.000000] RAMDISK: 7bc84000 - 7f745000
....
[    0.000000] Adding active range (0, 0x10, 0x95) 0 entries of 3200 used
[    0.000000] Adding active range (0, 0x100, 0x7f750) 1 entries of 3200 used
[    0.000000] Adding active range (0, 0x100000, 0x1080000) 2 entries of 3200 used
[    0.000000] Adding active range (1, 0x1080000, 0x2080000) 3 entries of 3200 used
[    0.000000] Adding active range (2, 0x2080000, 0x3080000) 4 entries of 3200 used
[    0.000000] Adding active range (3, 0x3080000, 0x4080000) 5 entries of 3200 used
[    0.000000] Adding active range (4, 0x4080000, 0x5080000) 6 entries of 3200 used
[    0.000000] Adding active range (5, 0x5080000, 0x6080000) 7 entries of 3200 used
[    0.000000] Adding active range (6, 0x6080000, 0x7080000) 8 entries of 3200 used
[    0.000000] Adding active range (7, 0x7080000, 0x8080000) 9 entries of 3200 used
[    0.000000] init_memory_mapping: [0x00000100000000-0x0000107fffffff]
[    0.000000]  0100000000 - 1080000000 page 2M
[    0.000000] kernel direct mapping tables up to 1080000000 @ [0x107ffbd000-0x107fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x107ffc2000-0x107fffffff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00001080000000-0x0000207fffffff]
[    0.000000]  1080000000 - 2080000000 page 2M
[    0.000000] kernel direct mapping tables up to 2080000000 @ [0x207ff7d000-0x207fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x207ffc0000-0x207fffffff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00002080000000-0x0000307fffffff]
[    0.000000]  2080000000 - 3080000000 page 2M
[    0.000000] kernel direct mapping tables up to 3080000000 @ [0x307ff3d000-0x307fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x307ffc0000-0x307fffffff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00003080000000-0x0000407fffffff]
[    0.000000]  3080000000 - 4080000000 page 2M
[    0.000000] kernel direct mapping tables up to 4080000000 @ [0x407fefd000-0x407fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x407ffc0000-0x407fffffff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00004080000000-0x0000507fffffff]
[    0.000000]  4080000000 - 5080000000 page 2M
[    0.000000] kernel direct mapping tables up to 5080000000 @ [0x507febd000-0x507fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x507ffc0000-0x507fffffff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00005080000000-0x0000607fffffff]
[    0.000000]  5080000000 - 6080000000 page 2M
[    0.000000] kernel direct mapping tables up to 6080000000 @ [0x607fe7d000-0x607fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x607ffc0000-0x607fffffff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00006080000000-0x0000707fffffff]
[    0.000000]  6080000000 - 7080000000 page 2M
[    0.000000] kernel direct mapping tables up to 7080000000 @ [0x707fe3d000-0x707fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x707ffc0000-0x707fffffff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00007080000000-0x0000807fffffff]
[    0.000000]  7080000000 - 8080000000 page 2M
[    0.000000] kernel direct mapping tables up to 8080000000 @ [0x807fdfc000-0x807fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x807ffbf000-0x807fffffff]          PGTABLE
[    0.000000] Initmem setup node 0 [0000000000000000-000000107fffffff]
[    0.000000]   NODE_DATA [0x0000107ffbd000-0x0000107ffc1fff]
[    0.000000] Initmem setup node 1 [0000001080000000-000000207fffffff]
[    0.000000]   NODE_DATA [0x0000207ffbb000-0x0000207ffbffff]
[    0.000000] Initmem setup node 2 [0000002080000000-000000307fffffff]
[    0.000000]   NODE_DATA [0x0000307ffbb000-0x0000307ffbffff]
[    0.000000] Initmem setup node 3 [0000003080000000-000000407fffffff]
[    0.000000]   NODE_DATA [0x0000407ffbb000-0x0000407ffbffff]
[    0.000000] Initmem setup node 4 [0000004080000000-000000507fffffff]
[    0.000000]   NODE_DATA [0x0000507ffbb000-0x0000507ffbffff]
[    0.000000] Initmem setup node 5 [0000005080000000-000000607fffffff]
[    0.000000]   NODE_DATA [0x0000607ffbb000-0x0000607ffbffff]
[    0.000000] Initmem setup node 6 [0000006080000000-000000707fffffff]
[    0.000000]   NODE_DATA [0x0000707ffbb000-0x0000707ffbffff]
[    0.000000] Initmem setup node 7 [0000007080000000-000000807fffffff]
[    0.000000]   NODE_DATA [0x0000807ffba000-0x0000807ffbefff]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D1933D1.9020609@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

While dubug kdump, found current kernel will have problem with crashkernel=512M.

It turns out that initial mapping is to 512M, and later initial mapping to 4G
(acutally is 2040M in my platform), will put page table near 512M.
then initial mapping to 128g will be near 2g.

before this patch:
[    0.000000] initial memory mapped : 0 - 20000000
[    0.000000] init_memory_mapping: [0x00000000000000-0x0000007f74ffff]
[    0.000000]  0000000000 - 007f600000 page 2M
[    0.000000]  007f600000 - 007f750000 page 4k
[    0.000000] kernel direct mapping tables up to 7f750000 @ [0x1fffc000-0x1fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x1fffc000-0x1fffdfff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00000100000000-0x0000207fffffff]
[    0.000000]  0100000000 - 2080000000 page 2M
[    0.000000] kernel direct mapping tables up to 2080000000 @ [0x7bc01000-0x7bc83fff]
[    0.000000]     memblock_x86_reserve_range: [0x7bc01000-0x7bc7efff]          PGTABLE
[    0.000000] RAMDISK: 7bc84000 - 7f745000
[    0.000000] crashkernel reservation failed - No suitable area found.

after patch:
[    0.000000] initial memory mapped : 0 - 20000000
[    0.000000] init_memory_mapping: [0x00000000000000-0x0000007f74ffff]
[    0.000000]  0000000000 - 007f600000 page 2M
[    0.000000]  007f600000 - 007f750000 page 4k
[    0.000000] kernel direct mapping tables up to 7f750000 @ [0x7f74c000-0x7f74ffff]
[    0.000000]     memblock_x86_reserve_range: [0x7f74c000-0x7f74dfff]          PGTABLE
[    0.000000] init_memory_mapping: [0x00000100000000-0x0000207fffffff]
[    0.000000]  0100000000 - 2080000000 page 2M
[    0.000000] kernel direct mapping tables up to 2080000000 @ [0x207ff7d000-0x207fffffff]
[    0.000000]     memblock_x86_reserve_range: [0x207ff7d000-0x207fffafff]          PGTABLE
[    0.000000] RAMDISK: 7bc84000 - 7f745000
[    0.000000]     memblock_x86_reserve_range: [0x17000000-0x36ffffff]     CRASH KERNEL
[    0.000000] Reserving 512MB of memory at 368MB for crashkernel (System RAM: 133120MB)

It means with the patch, page table for [0, 2g) will need 2g, instead of under 512M,
page table for [4g, 128g) will be near 128g, instead of under 2g.

That would good, if we have lots of memory above 4g, like 1024g, or 2048g or 16T, will not put
related page table under 2g. that would be have chance to fill the under 2g if 1G or 2M page is
not used.

the code change will use add map_low_page() and update unmap_low_page() for 64bit, and use them
to get access the corresponding high memory for page table setting.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D0C0734.7060900@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

commit 5bd5a452(x86: Add NX protection for kernel data) marked the
trampoline area NX - which unsurprisingly breaks resume and cpu
hotplug.

Revert the portion of that commit, which touches the trampoline.

Originally-from: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <1290410581.2405.24.camel@minggr.sh.intel.com>
Cc: Matthieu Castet <castet.matthieu@free.fr>
Cc: Siarhei Liakh <sliakh.lkml@gmail.com>
Cc: Xuxian Jiang <jiang@cs.ncsu.edu>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Andi Kleen <andi@firstfloor.org>
Tested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This patch expands functionality of CONFIG_DEBUG_RODATA to set main
(static) kernel data area as NX.

The following steps are taken to achieve this:

 1. Linker script is adjusted so .text always starts and ends on a page bound
 2. Linker script is adjusted so .rodata always start and end on a page boundary
 3. NX is set for all pages from _etext through _end in mark_rodata_ro.
 4. free_init_pages() sets released memory NX in arch/x86/mm/init.c
 5. bios rom is set to x when pcibios is used.

The results of patch application may be observed in the diff of kernel page
table dumps:

pcibios:

 -- data_nx_pt_before.txt       2009-10-13 07:48:59.000000000 -0400
 ++ data_nx_pt_after.txt        2009-10-13 07:26:46.000000000 -0400
  0x00000000-0xc0000000           3G                           pmd
  ---[ Kernel Mapping ]---
 -0xc0000000-0xc0100000           1M     RW             GLB x  pte
 +0xc0000000-0xc00a0000         640K     RW             GLB NX pte
 +0xc00a0000-0xc0100000         384K     RW             GLB x  pte
 -0xc0100000-0xc03d7000        2908K     ro             GLB x  pte
 +0xc0100000-0xc0318000        2144K     ro             GLB x  pte
 +0xc0318000-0xc03d7000         764K     ro             GLB NX pte
 -0xc03d7000-0xc0600000        2212K     RW             GLB x  pte
 +0xc03d7000-0xc0600000        2212K     RW             GLB NX pte
  0xc0600000-0xf7a00000         884M     RW         PSE GLB NX pmd
  0xf7a00000-0xf7bfe000        2040K     RW             GLB NX pte
  0xf7bfe000-0xf7c00000           8K                           pte

No pcibios:

 -- data_nx_pt_before.txt       2009-10-13 07:48:59.000000000 -0400
 ++ data_nx_pt_after.txt        2009-10-13 07:26:46.000000000 -0400
  0x00000000-0xc0000000           3G                           pmd
  ---[ Kernel Mapping ]---
 -0xc0000000-0xc0100000           1M     RW             GLB x  pte
 +0xc0000000-0xc0100000           1M     RW             GLB NX pte
 -0xc0100000-0xc03d7000        2908K     ro             GLB x  pte
 +0xc0100000-0xc0318000        2144K     ro             GLB x  pte
 +0xc0318000-0xc03d7000         764K     ro             GLB NX pte
 -0xc03d7000-0xc0600000        2212K     RW             GLB x  pte
 +0xc03d7000-0xc0600000        2212K     RW             GLB NX pte
  0xc0600000-0xf7a00000         884M     RW         PSE GLB NX pmd
  0xf7a00000-0xf7bfe000        2040K     RW             GLB NX pte
  0xf7bfe000-0xf7c00000           8K                           pte

The patch has been originally developed for Linux 2.6.34-rc2 x86 by
Siarhei Liakh <sliakh.lkml@gmail.com> and Xuxian Jiang <jiang@cs.ncsu.edu>.

 -v1:  initial patch for 2.6.30
 -v2:  patch for 2.6.31-rc7
 -v3:  moved all code into arch/x86, adjusted credits
 -v4:  fixed ifdef, removed credits from CREDITS
 -v5:  fixed an address calculation bug in mark_nxdata_nx()
 -v6:  added acked-by and PT dump diff to commit log
 -v7:  minor adjustments for -tip
 -v8:  rework with the merge of "Set first MB as RW+NX"
Signed-off-by: NSiarhei Liakh <sliakh.lkml@gmail.com>
Signed-off-by: NXuxian Jiang <jiang@cs.ncsu.edu>
Signed-off-by: NMatthieu CASTET <castet.matthieu@free.fr>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: James Morris <jmorris@namei.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Dave Jones <davej@redhat.com>
Cc: Kees Cook <kees.cook@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <4CE2F82E.60601@free.fr>
[ minor cleanliness edits ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NZimny Lech <napohybelskurwysynom2010@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Take mm->page_table_lock while syncing the vmalloc region.  This prevents
a race with the Xen pagetable pin/unpin code, which expects that the
page_table_lock is already held.  If this race occurs, then Xen can see
an inconsistent page type (a page can either be read/write or a pagetable
page, and pin/unpin converts it between them), which will cause either
the pin or the set_p[gm]d to fail; either will crash the kernel.

vmalloc_sync_all() should be called rarely, so this extra use of
page_table_lock should not interfere with its normal users.

The mm pointer is stashed in the pgd page's index field, as that won't
be otherwise used for pgds.
Reported-by: NIan Campbell <ian.cambell@eu.citrix.com>
Originally-by: NJan Beulich <jbeulich@novell.com>
LKML-Reference: <4CB88A4C.1080305@goop.org>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Whitespace cleanup only.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

When operating on whole pages, use clear_page() and copy_page() in
favor of memset() and memcpy(); after all that's what they are
intended for.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
LKML-Reference: <4C7FB8CA0200007800013F51@vpn.id2.novell.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This re-adds the lost chunk in commit 9b861528.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Haicheng Li <haicheng.li@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <20100903090407.GA19771@localhost>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Requested by Ingo, Thomas and HPA.

The old bootmem code is no longer necessary, and the transition is
complete.  Remove it.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

memblock_memory_size() will return memory size in memblock.memory.region.
memblock_free_memory_size() will return free memory size in memblock.memory.region.

So We can get exact reseved size in specified range.

Set the size right after initmem_init(), because later bootmem API will
get area above 16M. (except some fallback).

Later after we remove the bootmem, We could call that just before paging_init().
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

1.include linux/memblock.h directly. so later could reduce e820.h reference.
2 this patch is done by sed scripts mainly

-v2: use MEMBLOCK_ERROR instead of -1ULL or -1UL
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

It will be used memblock_x86_to_bootmem converting

It is an wrapper for reserve_bootmem, and x86 64bit is using special one.

Also clean up that version for x86_64. We don't need to take care of numa
path for that, bootmem can handle it how
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

When memory hotplug-adding happens for a large enough area
that a new PGD entry is needed for the direct mapping, the PGDs
of other processes would not get updated. This leads to some CPUs
oopsing like below when they have to access the unmapped areas.

[ 1139.243192] BUG: soft lockup - CPU#0 stuck for 61s! [bash:6534]
[ 1139.243195] Modules linked in: ipv6 autofs4 rfcomm l2cap crc16 bluetooth rfkill binfmt_misc
dm_mirror dm_region_hash dm_log dm_multipath dm_mod video output sbs sbshc fan battery ac parport_pc
lp parport joydev usbhid processor thermal thermal_sys container button rtc_cmos rtc_core rtc_lib
i2c_i801 i2c_core pcspkr uhci_hcd ohci_hcd ehci_hcd usbcore
[ 1139.243229] irq event stamp: 8538759
[ 1139.243230] hardirqs last  enabled at (8538759): [<ffffffff8100c3fc>] restore_args+0x0/0x30
[ 1139.243236] hardirqs last disabled at (8538757): [<ffffffff810422df>] __do_softirq+0x106/0x146
[ 1139.243240] softirqs last  enabled at (8538758): [<ffffffff81042310>] __do_softirq+0x137/0x146
[ 1139.243245] softirqs last disabled at (8538743): [<ffffffff8100cb5c>] call_softirq+0x1c/0x34
[ 1139.243249] CPU 0:
[ 1139.243250] Modules linked in: ipv6 autofs4 rfcomm l2cap crc16 bluetooth rfkill binfmt_misc
dm_mirror dm_region_hash dm_log dm_multipath dm_mod video output sbs sbshc fan battery ac parport_pc
lp parport joydev usbhid processor thermal thermal_sys container button rtc_cmos rtc_core rtc_lib
i2c_i801 i2c_core pcspkr uhci_hcd ohci_hcd ehci_hcd usbcore
[ 1139.243284] Pid: 6534, comm: bash Tainted: G   M       2.6.32-haicheng-cpuhp #7 QSSC-S4R
[ 1139.243287] RIP: 0010:[<ffffffff810ace35>]  [<ffffffff810ace35>] alloc_arraycache+0x35/0x69
[ 1139.243292] RSP: 0018:ffff8802799f9d78  EFLAGS: 00010286
[ 1139.243295] RAX: ffff8884ffc00000 RBX: ffff8802799f9d98 RCX: 0000000000000000
[ 1139.243297] RDX: 0000000000190018 RSI: 0000000000000001 RDI: ffff8884ffc00010
[ 1139.243300] RBP: ffffffff8100c34e R08: 0000000000000002 R09: 0000000000000000
[ 1139.243303] R10: ffffffff8246dda0 R11: 000000d08246dda0 R12: ffff8802599bfff0
[ 1139.243305] R13: ffff88027904c040 R14: ffff8802799f8000 R15: 0000000000000001
[ 1139.243308] FS:  00007fe81bfe86e0(0000) GS:ffff88000d800000(0000) knlGS:0000000000000000
[ 1139.243311] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1139.243313] CR2: ffff8884ffc00000 CR3: 000000026cf2d000 CR4: 00000000000006f0
[ 1139.243316] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1139.243318] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 1139.243321] Call Trace:
[ 1139.243324]  [<ffffffff810ace29>] ? alloc_arraycache+0x29/0x69
[ 1139.243328]  [<ffffffff8135004e>] ? cpuup_callback+0x1b0/0x32a
[ 1139.243333]  [<ffffffff8105385d>] ? notifier_call_chain+0x33/0x5b
[ 1139.243337]  [<ffffffff810538a4>] ? __raw_notifier_call_chain+0x9/0xb
[ 1139.243340]  [<ffffffff8134ecfc>] ? cpu_up+0xb3/0x152
[ 1139.243344]  [<ffffffff813388ce>] ? store_online+0x4d/0x75
[ 1139.243348]  [<ffffffff811e53f3>] ? sysdev_store+0x1b/0x1d
[ 1139.243351]  [<ffffffff8110589f>] ? sysfs_write_file+0xe5/0x121
[ 1139.243355]  [<ffffffff810b539d>] ? vfs_write+0xae/0x14a
[ 1139.243358]  [<ffffffff810b587f>] ? sys_write+0x47/0x6f
[ 1139.243362]  [<ffffffff8100b9ab>] ? system_call_fastpath+0x16/0x1b

This patch makes sure to always replicate new direct mapping PGD entries
to the PGDs of all processes, as well as ensures corresponding vmemmap
mapping gets synced.

V1: initial code by Andi Kleen.
V2: fix several issues found in testing.
V3: as suggested by Wu Fengguang, reuse common code of vmalloc_sync_all().

[ hpa: changed pgd_change from int to bool ]
Originally-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NHaicheng Li <haicheng.li@linux.intel.com>
LKML-Reference: <4C6E4FD8.6080100@linux.intel.com>
Reviewed-by: NWu Fengguang <fengguang.wu@intel.com>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

No behavior change.

Move some of vmalloc_sync_all() code into a new function
sync_global_pgds() that will be useful for memory hotplug.
Signed-off-by: NHaicheng Li <haicheng.li@linux.intel.com>
LKML-Reference: <4C6E4ECD.1090607@linux.intel.com>
Reviewed-by: NWu Fengguang <fengguang.wu@intel.com>
Reviewed-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

pavel@suse.cz no longer works, replace it with working address.
Signed-off-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Add vmemmap_alloc_block_buf for mem map only.

It will fallback to the old way if it cannot get a block that big.

Before this patch, when a node have 128g ram installed, memmap are
split into two parts or more.
[    0.000000]  [ffffea0000000000-ffffea003fffffff] PMD -> [ffff880100600000-ffff88013e9fffff] on node 1
[    0.000000]  [ffffea0040000000-ffffea006fffffff] PMD -> [ffff88013ec00000-ffff88016ebfffff] on node 1
[    0.000000]  [ffffea0070000000-ffffea007fffffff] PMD -> [ffff882000600000-ffff8820105fffff] on node 0
[    0.000000]  [ffffea0080000000-ffffea00bfffffff] PMD -> [ffff882010800000-ffff8820507fffff] on node 0
[    0.000000]  [ffffea00c0000000-ffffea00dfffffff] PMD -> [ffff882050a00000-ffff8820709fffff] on node 0
[    0.000000]  [ffffea00e0000000-ffffea00ffffffff] PMD -> [ffff884000600000-ffff8840205fffff] on node 2
[    0.000000]  [ffffea0100000000-ffffea013fffffff] PMD -> [ffff884020800000-ffff8840607fffff] on node 2
[    0.000000]  [ffffea0140000000-ffffea014fffffff] PMD -> [ffff884060a00000-ffff8840709fffff] on node 2
[    0.000000]  [ffffea0150000000-ffffea017fffffff] PMD -> [ffff886000600000-ffff8860305fffff] on node 3
[    0.000000]  [ffffea0180000000-ffffea01bfffffff] PMD -> [ffff886030800000-ffff8860707fffff] on node 3
[    0.000000]  [ffffea01c0000000-ffffea01ffffffff] PMD -> [ffff888000600000-ffff8880405fffff] on node 4
[    0.000000]  [ffffea0200000000-ffffea022fffffff] PMD -> [ffff888040800000-ffff8880707fffff] on node 4
[    0.000000]  [ffffea0230000000-ffffea023fffffff] PMD -> [ffff88a000600000-ffff88a0105fffff] on node 5
[    0.000000]  [ffffea0240000000-ffffea027fffffff] PMD -> [ffff88a010800000-ffff88a0507fffff] on node 5
[    0.000000]  [ffffea0280000000-ffffea029fffffff] PMD -> [ffff88a050a00000-ffff88a0709fffff] on node 5
[    0.000000]  [ffffea02a0000000-ffffea02bfffffff] PMD -> [ffff88c000600000-ffff88c0205fffff] on node 6
[    0.000000]  [ffffea02c0000000-ffffea02ffffffff] PMD -> [ffff88c020800000-ffff88c0607fffff] on node 6
[    0.000000]  [ffffea0300000000-ffffea030fffffff] PMD -> [ffff88c060a00000-ffff88c0709fffff] on node 6
[    0.000000]  [ffffea0310000000-ffffea033fffffff] PMD -> [ffff88e000600000-ffff88e0305fffff] on node 7
[    0.000000]  [ffffea0340000000-ffffea037fffffff] PMD -> [ffff88e030800000-ffff88e0707fffff] on node 7

after patch will get
[    0.000000]  [ffffea0000000000-ffffea006fffffff] PMD -> [ffff880100200000-ffff88016e5fffff] on node 0
[    0.000000]  [ffffea0070000000-ffffea00dfffffff] PMD -> [ffff882000200000-ffff8820701fffff] on node 1
[    0.000000]  [ffffea00e0000000-ffffea014fffffff] PMD -> [ffff884000200000-ffff8840701fffff] on node 2
[    0.000000]  [ffffea0150000000-ffffea01bfffffff] PMD -> [ffff886000200000-ffff8860701fffff] on node 3
[    0.000000]  [ffffea01c0000000-ffffea022fffffff] PMD -> [ffff888000200000-ffff8880701fffff] on node 4
[    0.000000]  [ffffea0230000000-ffffea029fffffff] PMD -> [ffff88a000200000-ffff88a0701fffff] on node 5
[    0.000000]  [ffffea02a0000000-ffffea030fffffff] PMD -> [ffff88c000200000-ffff88c0701fffff] on node 6
[    0.000000]  [ffffea0310000000-ffffea037fffffff] PMD -> [ffff88e000200000-ffff88e0701fffff] on node 7

-v2: change buf to vmemmap_buf instead according to Ingo
     also add CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER according to Ingo
-v3: according to Andrew, use sizeof(name) instead of hard coded 15
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-19-git-send-email-yinghai@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Finally we can use early_res to replace bootmem for x86_64 now.

Still can use CONFIG_NO_BOOTMEM to enable it or not.

-v2: fix 32bit compiling about MAX_DMA32_PFN
-v3: folded bug fix from LKML message below
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B747239.4070907@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Simplify setup_node_mem: don't use bootmem from other node, instead
just find_e820_area in early_node_mem.

This keeps the boundary between early_res and boot mem more clear, and
lets us only call early_res_to_bootmem() one time instead of for all
nodes.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-12-git-send-email-yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Newly added memory can not be accessed via /dev/mem, because we do not
update the variables high_memory, max_pfn and max_low_pfn.

Add a function update_end_of_memory_vars() to update these variables for
64-bit kernels.

[akpm@linux-foundation.org: simplify comment]
Signed-off-by: NShaohui Zheng <shaohui.zheng@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Li Haicheng <haicheng.li@intel.com>
Reviewed-by: NWu Fengguang <fengguang.wu@intel.com>
Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

set_kernel_text_rw()/set_kernel_text_ro() are marking pages
starting from _text to __start_rodata as RW or RO.

With CONFIG_DEBUG_RODATA, there might be free pages (associated
with padding the sections to 2MB large page boundary) between
text and rodata sections that are given back to page allocator.
So we should use only use the start (__text) and end
(__stop___ex_table) of the text section in
set_kernel_text_rw()/set_kernel_text_ro().
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Tested-by: NSteven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20091029024821.164525222@sbs-t61.sc.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Steven Rostedt reported that we are unconditionally making the
kernel text mapping as read-only. i.e., if someone does cpa() to
the kernel text area for setting/clearing any page table
attribute, we unconditionally clear the read-write attribute for
the kernel text mapping that is set at compile time.

We should delay (to forbid the write attribute) and enforce only
after the kernel has mapped the text as read-only.
Reported-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Tested-by: NSteven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20091029024820.996634347@sbs-t61.sc.intel.com>
[ marked kernel_set_to_readonly as __read_mostly ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

CONFIG_DEBUG_RODATA chops the large pages spanning boundaries of kernel
text/rodata/data to small 4KB pages as they are mapped with different
attributes (text as RO, RODATA as RO and NX etc).

On x86_64, preserve the large page mappings for kernel text/rodata/data
boundaries when CONFIG_DEBUG_RODATA is enabled. This is done by allowing the
RODATA section to be hugepage aligned and having same RWX attributes
for the 2MB page boundaries

Extra Memory pages padding the sections will be freed during the end of the boot
and the kernel identity mappings will have different RWX permissions compared to
the kernel text mappings.

Kernel identity mappings to these physical pages will be mapped with smaller
pages but large page mappings are still retained for kernel text,rodata,data
mappings.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20091014220254.190119924@sbs-t61.sc.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

In the first 2MB, kernel text is co-located with kernel static
page tables setup by head_64.S.  CONFIG_DEBUG_RODATA chops this
2MB large page mapping to small 4KB pages as we mark the kernel text as RO,
leaving the static page tables as RW.

With CONFIG_DEBUG_RODATA disabled, OLTP run on NHM-EP shows 1% improvement
with 2% reduction in system time and 1% improvement in iowait idle time.

To recover this, move the kernel static page tables to .data section, so that
we don't have to break the first 2MB of kernel text to small pages with
CONFIG_DEBUG_RODATA.
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20091014220254.063193621@sbs-t61.sc.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

To eventually interleave emulated nodes over physical nodes, we
need to know the physical topology of the machine without actually
registering it.  This does the k8 node setup in two parts:
detection and registration.  NUMA emulation can then used the
physical topology detected to setup the address ranges of emulated
nodes accordingly.  If emulation isn't used, the k8 nodes are
registered as normal.

Two formals are added to the x86 NUMA setup functions: `acpi' and
`k8'. These represent whether ACPI or K8 NUMA has been detected;
both cannot be true at the same time.  This specifies to the NUMA
emulation code whether an underlying physical NUMA topology exists
and which interface to use.

This patch deals solely with separating the k8 setup path into
Northbridge detection and registration steps and leaves the ACPI
changes for a subsequent patch.  The `acpi' formal is added here,
however, to avoid touching all the header files again in the next
patch.

This approach also ensures emulated nodes will not span physical
nodes so the true memory latency is not misrepresented.

k8_get_nodes() may now be used to export the k8 physical topology
of the machine for NUMA emulation.
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Ankita Garg <ankita@in.ibm.com>
Cc: Len Brown <len.brown@intel.com>
LKML-Reference: <alpine.DEB.1.00.0909251518400.14754@chino.kir.corp.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Some archs define MODULED_VADDR/MODULES_END which is not in VMALLOC area.
This is handled only in x86-64.  This patch make it more generic.  And we
can use vread/vwrite to access the area.  Fix it.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For /proc/kcore, each arch registers its memory range by kclist_add().
In usual,

	- range of physical memory
	- range of vmalloc area
	- text, etc...

are registered but "range of physical memory" has some troubles.  It
doesn't updated at memory hotplug and it tend to include unnecessary
memory holes.  Now, /proc/iomem (kernel/resource.c) includes required
physical memory range information and it's properly updated at memory
hotplug.  Then, it's good to avoid using its own code(duplicating
information) and to rebuild kclist for physical memory based on
/proc/iomem.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some 64bit arch has special segment for mapping kernel text.  It should be
entried to /proc/kcore in addtion to direct-linear-map, vmalloc area.
This patch unifies KCORE_TEXT entry scattered under x86 and ia64.

I'm not familiar with other archs (mips has its own even after this patch)
but range of [_stext ..._end) is a valid area of text and it's not in
direct-map area, defining CONFIG_ARCH_PROC_KCORE_TEXT is only a necessary
thing to do.

Note: I left mips as it is now.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For /proc/kcore, vmalloc areas are registered per arch.  But, all of them
registers same range of [VMALLOC_START...VMALLOC_END) This patch unifies
them.  By this.  archs which have no kclist_add() hooks can see vmalloc
area correctly.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Presently, kclist_add() only eats start address and size as its arguments.
Considering to make kclist dynamically reconfigulable, it's necessary to
know which kclists are for System RAM and which are not.

This patch add kclist types as
  KCORE_RAM
  KCORE_VMALLOC
  KCORE_TEXT
  KCORE_OTHER

This "type" is used in a patch following this for detecting KCORE_RAM.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 96177299 ("Drop free_pages()")
modified nr_free_pages() to return 'unsigned long' instead of 'unsigned
int'.  This made the casts to 'unsigned long' in most callers superfluous,
so remove them.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NGeert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NKyle McMartin <kyle@mcmartin.ca>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <zankel@tensilica.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This line looks suspicious, because if this is true, then the
'flags' parameter of function reserve_bootmem_generic() will be
unused when !CONFIG_NUMA. I don't think this is what we want.
Signed-off-by: NWANG Cong <amwang@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: akpm@linux-foundation.org
LKML-Reference: <20090821083709.5098.52505.sendpatchset@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This line looks suspicious, because if this is true, then the
'flags' parameter of function reserve_bootmem_generic() will be
unused when !CONFIG_NUMA. I don't think this is what we want.
Signed-off-by: NWANG Cong <amwang@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: akpm@linux-foundation.org
LKML-Reference: <20090821083709.5098.52505.sendpatchset@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Alex found that specjbb2005 still can not run with hugepages on an
x86-64 machine.  This only happens when numa is not compiled in.

The root cause: node_set_state will not set it back for us in that case,
so don't clear that when numa is not select in config

[ v2: use node_clear_state instead ]
Reported-and-Tested-by: NAlex Shi <alex.shi@intel.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Nathan reported that

| commit 73d60b7f
| Author: Yinghai Lu <yinghai@kernel.org>
| Date:   Tue Jun 16 15:33:00 2009 -0700
|
|    page-allocator: clear N_HIGH_MEMORY map before we set it again
|
|    SRAT tables may contains nodes of very small size.  The arch code may
|    decide to not activate such a node.  However, currently the early boot
|    code sets N_HIGH_MEMORY for such nodes.  These nodes therefore seem to be
|    active although these nodes have no present pages.
|
|    For 64bit N_HIGH_MEMORY == N_NORMAL_MEMORY, so that works for 64 bit too

unintentionally and incorrectly clears the cpuset.mems cgroup attribute on
an i386 kvm guest, meaning that cpuset.mems can not be used.

Fix this by only clearing node_states[N_NORMAL_MEMORY] for 64bit only.
and need to do save/restore for that in find_zone_movable_pfn
Reported-by: NNathan Lynch <ntl@pobox.com>
Tested-by: NNathan Lynch <ntl@pobox.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>,
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>