don't assume we can use RAM near the end of every node.
Esp systems that have few memory and they could have
kva address and kva RAM all below max_low_pfn.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now we are using register_e820_active_regions() instead of
add_active_range() directly. So end_pfn could be different between the
value in early_node_map to node_end_pfn.
So we need to make shrink_active_range() smarter.
shrink_active_range() is a generic MM function in mm/page_alloc.c but
it is only used on 32-bit x86. Should we move it back to some file in
arch/x86?
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
this way 32-bit is more similar to 64-bit, and smarter e820 and numa.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
when 1/3 user/kernel split is used, and less memory is installed, or if
we have a big hole below 4g, max_low_pfn is still using 3g-128m
try to go down from max_low_pfn until we get it. otherwise will panic.
need to make 32-bit code to use register_e820_active_regions ... later.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
on 32-bit in head_32.S after initial page table is done, we get initial
max_pfn_mapped, and then kernel_physical_mapping_init will give us
a final one.
We need to use that to make sure find_e820_area will get valid addresses
for boot_map and for NODE_DATA(0) on numa32.
XEN PV and lguest may need to assign max_pfn_mapped too.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
we don't need to call memory_present that early.
numa and sparse will call memory_present later and might
even fail, it will call memory_present for the full range.
also for sparse it will call alloc_bootmem ... before we set up bootmem.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
... otherwise alloc_remap will not get node_mem_map from kva area, and
alloc_node_mem_map has to alloc_bootmem_node to get mem_map.
It will use two low address copies ...
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
so every element will represent 64M instead of 256M.
AMD opteron could have HW memory hole remapping, so could have
[0, 8g + 64M) on node0. Reduce element size to 64M to keep that on node 0
Later we need to use find_e820_area() to allocate memory_node_map like
on 64-bit. But need to move memory_present out of populate_mem_map...
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
reserve early numa kva, so it will not clash with new RAMDISK
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/pci/Makefile_32 has a nasty detail. VISWS and NUMAQ build
override the generic pci-y rules. This needs a proper cleanup, but
that needs more thoughts. Undo
commit 895d30935e
x86: numaq fix
do not override the existing pci-y rule when adding visws or
numaq rules.
There is also a stupid init function ordering problem vs. acpi.o
Add comments to the Makefile to avoid tripping over this again.
Remove the srat stub code in discontig_32.c to allow a proper NUMAQ
build.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
this function doesnt just 'find' the max_pfn - it also has
other side-effects such as registering sparse memory maps.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
we could call find_max_pfn() directly instead of setup_memory() to get
max_pfn needed for mtrr trimming.
otherwise setup_memory() is called two times... that is duplicated...
[ mingo@elte.hu: both Thomas and me simulated a double call to
setup_bootmem_allocator() and can confirm that it is a real bug
which can hang in certain configs. It's not been reported yet but
that is probably due to the relatively scarce nature of
MTRR-trimming systems. ]
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.
This patch:
Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past. This is to avoid conflicts.
Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The DISCONTIG memory model on x86 32 bit uses a remap allocator early
in boot. The objective is that portions of every node are mapped in to
the kernel virtual area (KVA) in place of ZONE_NORMAL so that node-local
allocations can be made for pgdat and mem_map structures.
With SPARSEMEM, the amount that is set aside is insufficient for all the
mem_maps to be allocated. During the boot process, it falls back to using
the bootmem allocator. This breaks assumptions that SPARSEMEM makes about
the layout of the mem_map in memory and results in a VM_BUG_ON triggering
due to pfn_to_page() returning garbage values.
This patch only enables the remap allocator for use with DISCONTIG.
Without SRAT support, a compile-error occurs because ACPI table parsing
functions are only available in x86-64. This patch also adds no-op stubs
and prints a warning message. What likely needs to be done is sharing
the table parsing functions between 32 and 64 bit if they are
compatible.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
On 32-bit NUMA, the memmap representing struct pages on each node is
allocated from node-local memory if possible. As only node-0 has memory from
ZONE_NORMAL, the memmap must be mapped into low memory. This is done by
reserving space in the Kernel Virtual Area (KVA) for the memmap belonging
to other nodes by taking pages from the end of ZONE_NORMAL and remapping
the other nodes memmap into those virtual addresses. The node boundaries
are then adjusted so that the region of pages is not used and it is marked
as reserved in the bootmem allocator.
This reserved portion of the KVA is PMD aligned althought
strictly speaking that requirement could be lifted (see thread at
http://lkml.org/lkml/2007/8/24/220). The problem is that when aligned, there
may be a portion of ZONE_NORMAL at the end that is not used for memmap and
does not have an initialised memmap nor is it marked reserved in the bootmem
allocator. Later in the boot process, these pages are freed and a storm of
Bad page state messages result.
This patch marks these pages reserved that are wasted due to alignment
in the bootmem allocator so they are not accidently freed. It is worth
noting that memory from node-0 is wasted where it could have been put into
ZONE_HIGHMEM on NUMA machines. Worse, the KVA is always reserved from the
location of real memory even when there is plenty of spare virtual address
space.
This patch also makes sure that reserve_bootmem() is not called with a
0-length size in numa_kva_reserve(). When this happens, it usually means
that a kernel built for Summit is being booted on a normal machine. The
resulting BUG_ON() is misleading so it is caught here.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The boot protocol has until now required that the initrd be located in
lowmem, which makes the lowmem/highmem boundary visible to the boot
loader. This was exported to the bootloader via a compile-time
field. Unfortunately, the vmalloc= command-line option breaks this
part of the protocol; instead of adding yet another hack that affects
the bootloader, have the kernel relocate the initrd down below the
lowmem boundary inside the kernel itself.
Note that this does not rely on HIGHMEM being enabled in the kernel.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
node0_bdata and paddr_to_nid() can become static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch makes some needlessly global variables static.
[ tglx: arch/x86 adaptation ]
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andi Kleen <ak@suse.de>
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>