do that in init_memory_mapping
also remove one init_ohci1394_dma_on_all_controllers
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The patch "x86: introduce init_memory_mapping for 32bit" does not allocate
enough space for PTEs if the CPU does not implement PSE.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
... so can we use mem below max_low_pfn earlier.
this allows us to move several functions more early instead of waiting
to after paging_init.
That includes moving relocate_initrd() earlier in the bootup, and kva
related early setup done in initmem_init. (in followup patches)
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
those function depend on paging setup pgtable, so they could access
the ram in bootmem region but just get mapped.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
for 32bit
we already had early_res support, so don't need to track min_low_pfn.
keep it to 0 always.
also use init_bootmem_node instead of init_bootmem, so don't touch
min_low_pfn.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
so that max_low_pfn is not changed after it is set.
so we can move that early and out of initmem_init.
could call find_low_pfn_range just after max_pfn is set.
also could move reserve_initrd out of setup_bootmem_allocator
so 32bit is more like 64bit.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
want to remove arch_get_ram_range, and use early_node_map instead.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
so don't punish all other cpus without that problem when init highmem
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
use early_node_map to init high pages, so we can remove page_is_ram() and
page_is_reserved_early() in the big loop with add_one_highpage
also remove page_is_reserved_early(), it is not needed anymore.
v2: fix the build of other platforms
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
1. add reserve_bootmem_generic for 32bit
2. change len to unsigned long
3. make early_res_to_bootmem to use it
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add information about the mapping state of the direct mapping to
/proc/meminfo. I chose /proc/meminfo because that is where all the other
memory statistics are too and it is a generally useful metric even
outside debugging situations. A lot of split kernel pages means the
kernel will run slower.
This way we can see how many large pages are really used for it and how
many are split.
Useful for general insight into the kernel.
v2: Add hotplug locking to 64bit to plug a very obscure theoretical race.
32bit doesn't need it because it doesn't support hotadd for lowmem.
Fix some typos
v3: Rename dpages_cnt
Add CONFIG ifdef for count update as requested by tglx
Expand description
v4: Fix stupid bugs added in v3
Move update_page_count to pageattr.c
Signed-off-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch makes early reserved highmem pages become reserved
pages. This can be used for highmem pages allocated by bootloader such
as EFI memory map, linked list of setup_data, etc.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: andi@firstfloor.org
Cc: mingo@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Dynamic ftrace cant work when the kernel has its text write protected.
This patch keeps the kernel from being write protected when
dynamic ftrace is in place.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
After resume on a 2cpu laptop, kernel builds collapse with a sed hang,
sh or make segfault (often on 20295564), real-time signal to cc1 etc.
Several hurdles to jump, but a manually-assisted bisect led to -rc1's
d2bcbad5f3 x86: do not zap_low_mappings
in __smp_prepare_cpus. Though the low mappings were removed at bootup,
they were left behind (with Global flags helping to keep them in TLB)
after resume or cpu online, causing the crashes seen.
Reinstate zap_low_mappings (with local __flush_tlb_all) for each cpu_up
on x86_32. This used to be serialized by smp_commenced_mask: that's now
gone, but a low_mappings flag will do. No need for native_smp_cpus_done
to repeat the zap: let mem_init zap BSP's low mappings just like on UP.
(In passing, fix error code from native_cpu_up: do_boot_cpu returns a
variety of diagnostic values, Dprintk what it says but convert to -EIO.
And save_pg_dir separately before zap_low_mappings: doesn't matter now,
but zapping twice in succession wiped out resume's swsusp_pg_dir.)
That worked well on the duo and one quad, but wouldn't boot 3rd or 4th
cpu on P4 Xeon, oopsing just after unlock_ipi_call_lock. The TLB flush
IPI now being sent reveals a long-standing bug: the booting cpu has its
APIC readied in smp_callin at the top of start_secondary, but isn't put
into the cpu_online_map until just before that unlock_ipi_call_lock.
So native_smp_call_function_mask to online cpus would send_IPI_allbutself,
including the cpu just coming up, though it has been excluded from the
count to wait for: by the time it handles the IPI, the call data on
native_smp_call_function_mask's stack may well have been overwritten.
So fall back to send_IPI_mask while cpu_online_map does not match
cpu_callout_map: perhaps there's a better APICological fix to be
made at the start_secondary end, but I wouldn't know that.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
All architectures use an effectively identical definition of online_page(), so
just make it common code. x86-64, ia64, powerpc and sh are actually
identical; x86-32 is slightly different.
x86-32's differences arise because it puts its hotplug pages in the highmem
zone. We can handle this in the generic code by inspecting the page to see if
its in highmem, and update the totalhigh_pages count appropriately. This
leaves init_32.c:free_new_highpage with a single caller, so I folded it into
add_one_highpage_init.
I also removed an incorrect comment referring to the NUMA case; any NUMA
details have already been dealt with by the time online_page() is called.
[akpm@linux-foundation.org: fix indenting]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamez.hiroyu@jp.fujitsu.com>
Tested-by: KAMEZAWA Hiroyuki <kamez.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Christoph Lameter <clameter@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is claimed that NexGen CPUs were never shipped:
http://lkml.org/lkml/2008/4/20/179
Also, the kernel support for these chips has been broken for
a long time, the code intended to support NexGen thereby being
essentially dead.
As an outcome of the discussion that can be found using the URL
above, this patch removes the NexGen support altogether.
The changes in this patch survived a defconfig build for i386, a
couple of successful randconfig builds, as well as a runtime test,
which consisted in booting a 32-bit x86 box up to the shell prompt.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-pat:
generic: add ioremap_wc() interface wrapper
/dev/mem: make promisc the default
pat: cleanups
x86: PAT use reserve free memtype in mmap of /dev/mem
x86: PAT phys_mem_access_prot_allowed for dev/mem mmap
x86: PAT avoid aliasing in /dev/mem read/write
devmem: add range_is_allowed() check to mmap of /dev/mem
x86: introduce /dev/mem restrictions with a config option
Make KERNEL_PGD_PTRS common, as previously it was only being defined
for 32-bit.
There are a couple of follow-on changes from this:
- KERNEL_PGD_PTRS was being defined in terms of USER_PGD_PTRS. The
definition of USER_PGD_PTRS doesn't really make much sense on x86-64,
since it can have two different user address-space configurations.
I renamed USER_PGD_PTRS to KERNEL_PGD_BOUNDARY, which is meaningful
for all of 32/32, 32/64 and 64/64 process configurations.
- USER_PTRS_PER_PGD was also defined and was being used for similar
purposes. Converting its users to KERNEL_PGD_BOUNDARY left it
completely unused, and so I removed it.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Rename (alloc|release)_(pt|pd) to pte/pmd to explicitly match the name
of the appropriate pagetable level structure.
[ x86.git merge work by Mark McLoughlin <markmc@redhat.com> ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch introduces a restriction on /dev/mem: Only non-memory can be
read or written unless the newly introduced config option is set.
The X server needs access to /dev/mem for the PCI space, but it doesn't need
access to memory; both the file permissions and SELinux permissions of /dev/mem
just make X effectively super-super powerful. With the exception of the
BIOS area, there's just no valid app that uses /dev/mem on actual memory.
Other popular users of /dev/mem are rootkits and the like.
(note: mmap access of memory via /dev/mem was already not allowed since
a really long time)
People who want to use /dev/mem for kernel debugging can enable the config
option.
The restrictions of this patch have been in the Fedora and RHEL kernels for
at least 4 years without any problems.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Remove old comments that include the old arch/i386 directory.
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Intel recommends to not use large pages for the first 1MB
of the physical memory because there are fixed size MTRRs there
which cause splitups in the TLBs.
On AMD doing so is also a good idea.
The implementation is a little different between 32bit and 64bit.
On 32bit I just taught the initial page table set up about this
because it was very simple to do. This also has the advantage
that the risk of a prefetch ever seeing the page even
if it only exists for a short time is minimized.
On 64bit that is not quite possible, so use set_memory_4k() a little
later (in check_bugs) instead.
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: andreas.herrmann3@amd.com
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Even on 32bit 2MB pages can map more memory than is in the true
max_low_pfn if end_pfn is not highmem and not aligned to 2MB.
Add a end_pfn_map similar to x86-64 that accounts for this
fact. This is important for code that really needs to know about
all mapping aliases.
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: andreas.herrmann3@amd.com
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
extern should not appear in C files. Also, the definitions
do not match the prototype currently, not sure what way you
want to go with this, I've switched the prototype to return
int, but I can see going to the void return as well.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
DEBUG_PAGEALLOC was not possible on 64-bit due to its early-bootup
hardcoded reliance on PSE pages, and the unrobustness of the runtime
splitup of large pages. The splitup ended in recursive calls to
alloc_pages() when a page for a pte split was requested.
Avoid the recursion with a preallocated page pool, which is used to
split up large mappings and gets refilled in the return path of
kernel_map_pages after the split has been done. The size of the page
pool is adjusted to the available memory.
This part just implements the page pool and the initialization w/o
using it yet.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Specifically the boot time page tables in a CONFIG_X86_PAE=y enabled
kernel are in PAE format.
early_ioremap is updated to use the standard page table accessors.
Clear any mappings beyond max_low_pfn from the boot page tables in
native_pagetable_setup_start because the initial mappings can extend
beyond the range of physical memory and into the vmalloc area.
Derived from patches by Eric Biederman and H. Peter Anvin.
[ jeremy@goop.org: PAE swapper_pg_dir needs to be page-sized fix ]
Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Mika Penttilä <mika.penttila@kolumbus.fi>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Use the _ASM_EXTABLE macro from <asm/asm.h>, instead of open-coding
__ex_table entires in arch/x86/mm/init_32.c.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
swsusp_pg_dir[] is used for suspend, but not for hibernation.
clean-up the ifdefs which worked by accident, while implying the opposite.
Delete the __nosavedata, which also implied the opposite.
Some day we may optimize CONFIG_ACPI_SLEEP to build minimal kernels
for just hibernate or just suspend but not both,
but today isn't that day.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
In x86 PAE mode, stop treating pmds as a special case. Previously
they were always allocated and freed with the pgd. The modifies the
code to be the same as 64-bit mode, where they are allocated on
demand.
This is a step on the way to unifying 32/64-bit pagetable allocation
as much as possible.
There is a complicating wart, however. When you install a new
reference to a pmd in the pgd, the processor isn't guaranteed to see
it unless you reload cr3. Since reloading cr3 also has the
side-effect of flushing the tlb, this is an expense that we want to
avoid whereever possible.
This patch simply avoids reloading cr3 unless the update is to the
current pagetable. Later patches will optimise this further.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: William Irwin <wli@holomorphy.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
printk fixes. NOP in terms of functionality, but strings got
a bit larger due to the KERN_ markers that were added.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
debug incorrect/late access to init memory, by permanently unmapping
the init memory ranges. Depends on CONFIG_DEBUG_PAGEALLOC=y.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Latest update; I now have 4 NX tests, but 2 fail so they're #if 0'd.
I also cleaned up the NX test code quite a bit, and got rid of the ugly
exception table sorting stuff.
From: Arjan van de Ven <arjan@linux.intel.com>
This patch adds testcases for the CONFIG_DEBUG_RODATA configuration option
as well as the NX CPU feature/mappings. Both testcases can move to tests/
once that patch gets merged into mainline.
(I'm half considering moving the rodata test into mm/init.c but I'll
wait with that until init.c is unified)
As part of this I had to fix a not-quite-right alignment in the vmlinux.lds.h
for the RODATA sections, which lead to 1 page less being marked read only.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When we free initmem, various rodata and CPA checks may have left
memory read only.. this patch ensures that the memory is writable
before we free it.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The set_memory_* and set_pages_* family of API's currently requires the
callers to do a global tlb flush after the function call; forgetting this is
a very nasty deathtrap. This patch moves the global tlb flush into
each of the callers
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch converts various users of change_page_attr() to the new,
more intent driven set_page_*/set_memory_* API set.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The SMP trampoline always runs in real mode, so making it executable
in the page tables doesn't make much sense because it executes
before page tables are set up. That was the only user of
set_kernel_exec(). Remove set_kernel_exec().
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No need to make it 64bit there.
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch renames bt_ioremap to early_ioremap, which is used in
x86_64. This makes it easier to merge i386 and x86_64 usage.
[ mingo@elte.hu: fix ]
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch makes it possible for bt_ioremap() to be used before
paging_init(), via providing an early implementation of set_fixmap()
that can be used before paging_init().
This way boot_ioremap() can be replaced by bt_ioremap().
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
based on this patch from Andi Kleen:
| Subject: CPA: Return the page table level in lookup_address()
| From: Andi Kleen <ak@suse.de>
|
| Needed for the next change.
|
| And change all the callers.
and ported it to x86.git.
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
- Rename it to pte_exec() from pte_exec_kernel(). There is nothing
kernel specific in there.
- Move it into the common file because _PAGE_NX is 0 on !PAE and then
pte_exec() will be always evaluate to true.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When CONFIG_DEBUG_RODATA is enabled undo the ro mapping and redo it again.
This gives some simple testing for change_page_attr().
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Convert macros into inline functions, for better type-checking.
This patch required a little bit of fiddling with headers in order to
make __(pte|pmd)_free_tlb inline rather than macros.
asm-generic/tlb.h includes asm/pgalloc.h, though it doesn't directly
use any pgalloc definitions. I removed this include to avoid an
include cycle, but it may cause secondary compile failures by things
depending on the indirect inclusion; arch/x86/mm/hugetlbpage.c was one
such place; there may be others.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add mm to paravirt_alloc_pd, partly to make it consistent with
paravirt_alloc_pt, and because later changes will make use of it.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Make users of supported_pte_mask common. This has the side-effect of
introducing the variable for 32-bit non-PAE, but I think its a pretty
small cost to simplify the code.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Because the EFI memory map are converted to e820 memory map in bootloader, the
EFI memory map handling code is removed to clean up.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Some code reformatting in init_32.c. No functional change.
Signed-off-by: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Denys Fedoryshchenko reported a bootup crash when he upgraded
his system from 3GB to 4GB RAM:
http://lkml.org/lkml/2008/1/7/9
the bug is due to HIGHMEM4G && SPARSEMEM kernels making pfn_to_page()
to return an invalid pointer when the pfn is in a memory hole. The
256 MB PCI aperture at the end of RAM was not mapped by sparsemem,
and hence the pfn was not valid. But set_highmem_pages_init() iterated
this range without checking the pfn's validity first.
this bug was probably present in the sparsemem code ever since sparsemem
has been introduced in v2.6.13. It was masked due to HIGHMEM64G using
larger memory regions in sparsemem_32.h:
#ifdef CONFIG_X86_PAE
#define SECTION_SIZE_BITS 30
#define MAX_PHYSADDR_BITS 36
#define MAX_PHYSMEM_BITS 36
#else
#define SECTION_SIZE_BITS 26
#define MAX_PHYSADDR_BITS 32
#define MAX_PHYSMEM_BITS 32
#endif
which creates 1GB sparsemem regions instead of 64MB sparsemem regions.
So in practice we only ever created true sparsemem holes on x86 with
HIGHMEM4G - but that was rarely used by distros.
( btw., we could probably save 2MB of mem_map[]s on X86_PAE if we reduced
the sparsemem region size to 256 MB. )
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
if CONFIG_PAGEALLOC is enabled then X86_FEATURE_PSE is disabled and all
the kernel physical RAM pagetables are set up as 4K pages. This is
needed so that CONFIG_PAGEALLOC can do finegrained mapping and unmapping
of pages.
as a side-effect though, the total size of memory allocated as kernel
pagetables increases significantly. All these pagetables are allocated
via alloc_bootmem_low_pages(), straight out of the lowmem DMA pool. If
the system has enough RAM and a large kernel image then almost all of
the 16 MB lowmem DMA pool is allocated to the image and to pagetables -
leaving no space for __GFP_DMA allocations.
this results in drivers failing and the bootup hanging:
swapper invoked oom-killer: gfp_mask=0x80d1, order=0, oomkilladj=0
[<4015059f>] out_of_memory+0x17f/0x1c0
[<40151f3c>] __alloc_pages+0x37c/0x3a0
[<40168cd7>] slob_new_page+0x37/0x50
[<40168dff>] slob_alloc+0x10f/0x190
[<40169010>] __kmalloc_node+0x80/0x90
[<405a17e3>] scsi_host_alloc+0x33/0x2c0
[<405a1a82>] scsi_register+0x12/0x60
[<40d5889e>] aha1542_detect+0x9e/0x940
[<405c5ba5>] ultrastor_detect+0x265/0x5f0
[<401352f5>] getnstimeofday+0x35/0xf0
[<40d58751>] init_this_scsi_driver+0x41/0xf0
[<40d0b856>] kernel_init+0x136/0x310
[<40d58710>] init_this_scsi_driver+0x0/0xf0
[<40d0b720>] kernel_init+0x0/0x310
[<40105547>] kernel_thread_helper+0x7/0x10
=======================
the fix is to first allocate from above the DMA pool, and if that fails
(for example due to it being a machine with less than 16 MB of RAM),
allocate from the DMA pool as a fallback.
With this fix applied i was able to boot a PAGEALLOC=y kernel that would
hang before.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* 'xen-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xfs: eagerly remove vmap mappings to avoid upsetting Xen
xen: add some debug output for failed multicalls
xen: fix incorrect vcpu_register_vcpu_info hypercall argument
xen: ask the hypervisor how much space it needs reserved
xen: lock pte pages while pinning/unpinning
xen: deal with stale cr3 values when unpinning pagetables
xen: add batch completion callbacks
xen: yield to IPI target if necessary
Clean up duplicate includes in arch/i386/xen/
remove dead code in pgtable_cache_init
paravirt: clean up lazy mode handling
paravirt: refactor struct paravirt_ops into smaller pv_*_ops
The conversion from using a slab cache to quicklist left some residual
dead code.
I note that in the conversion it now always allocates a whole page for
the pgd, rather than the 32 bytes needed for a PAE pgd. Was this
intended?
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Now, arch dependent code around CONFIG_MEMORY_HOTREMOVE is a mess.
This patch cleans up them. This is against 2.6.23-rc6-mm1.
- fix compile failure on ia64/ CONFIG_MEMORY_HOTPLUG && !CONFIG_MEMORY_HOTREMOVE case.
- For !CONFIG_MEMORY_HOTREMOVE, add generic no-op remove_memory(),
which returns -EINVAL.
- removed remove_pages() only used in powerpc.
- removed no-op remove_memory() in i386, sh, sparc64, x86_64.
- only powerpc returns -ENOSYS at memory hot remove(no-op). changes it
to return -EINVAL.
Note:
Currently, only ia64 supports CONFIG_MEMORY_HOTREMOVE. I welcome other
archs if there are requirements and testers.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yinghai Lu