| Commit message (Collapse) | Author | Age |
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- Add support in ima_path_check() for integrity checking without
incrementing the counts. (Required for nfsd.)
- rename and export opencount_get to ima_counts_get
- replace ima_shm_check calls with ima_counts_get
- export ima_path_check
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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A number of IMA functions only used during init are not marked with __init.
Add those notations so they are freed automatically.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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The IMA TCB policy is dangerous. A normal use can use all of a system's
memory (which cannot be freed) simply by building and running lots of
executables. The TCB policy is also nearly useless because logging in as root
often causes a policy violation when dealing with utmp, thus rendering the
measurements meaningless.
There is no good fix for this in the kernel. A full TCB policy would need to
be loaded in userspace using LSM rule matching to get both a protected and
useful system. But, if too little is measured before userspace can load a real
policy one again ends up with a meaningless set of measurements. One option
would be to put the policy load inside the initrd in order to get it early
enough in the boot sequence to be useful, but this runs into trouble with the
LSM. For IMA to measure the LSM policy and the LSM policy loading mechanism
it needs rules to do so, but we already talked about problems with defaulting
to such broad rules....
IMA also depends on the files being measured to be on an FS which implements
and supports i_version. Since the only FS with this support (ext4) doesn't
even use it by default it seems silly to have any IMA rules by default.
This should reduce the performance overhead of IMA to near 0 while still
letting users who choose to configure their machine as such to inclue the
ima_tcb kernel paramenter and get measurements during boot before they can
load a customized, reasonable policy in userspace.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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On Tue, 2009-05-19 at 00:05 -0400, Eamon Walsh wrote:
> Recent versions of coreutils have bumped the read buffer size from 4K to
> 32K in several of the utilities.
>
> This means that "cat /selinux/booleans/xserver_object_manager" no longer
> works, it returns "Invalid argument" on F11. getsebool works fine.
>
> sel_read_bool has a check for "count > PAGE_SIZE" that doesn't seem to
> be present in the other read functions. Maybe it could be removed?
Yes, that check is obsoleted by the conversion of those functions to
using simple_read_from_buffer(), which will reduce count if necessary to
what is available in the buffer.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
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The selinuxfs superblock magic is used inside the IMA code, but is being
defined in two places and could someday get out of sync. This patch moves the
declaration into magic.h so it is only done once.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
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The IMA default policy measures every single file opened by root. This is
terrible for most users. Consider a system (like mine) with virtual machine
images. When those images are touched (which happens at boot for me) those
images are measured. This is just way too much for the default case.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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The IMA policy file does not implement read. Trying to just open/read/close
the file will load a blank policy and you cannot then change the policy
without a reboot. This removes the read permission from the file so one must
at least be attempting to write...
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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get_event_name uses sprintf to fill a buffer declared on the stack. It fills
the buffer 2 bytes at a time. What the code doesn't take into account is that
sprintf(buf, "%02x", data) actually writes 3 bytes. 2 bytes for the data and
then it nul terminates the string. Since we declare buf to be 40 characters
long and then we write 40 bytes of data into buf sprintf is going to write 41
characters. The fix is to leave room in buf for the nul terminator.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Both of the securityfs users (TPM and IMA) can call securityfs_remove and pass
an IS_ERR(dentry) in their failure paths. This patch handles those rather
than panicing when it tries to start deferencing some negative memory.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
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If IMA tried to measure a file which was larger than 4G dentry_open would fail
with -EOVERFLOW since IMA wasn't passing O_LARGEFILE. This patch passes
O_LARGEFILE to all IMA opens to avoid this problem.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Currently IMA does not handle failures from dentry_open(). This means that we
leave a pointer set to ERR_PTR(errno) and then try to use it just a few lines
later in fput(). Oops.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Proper invocation of the current credentials is to use current_cred() not
current->cred. This patches makes IMA use the new method.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Guard the setprocattr security hook against ptrace by taking the target task's
cred_guard_mutex around it. The problem is that setprocattr() may otherwise
note the lack of a debugger, and then perform an action on that basis whilst
letting a debugger attach between the two points. Holding cred_guard_mutex
across the test and the action prevents ptrace_attach() from doing that.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Rename cred_exec_mutex to reflect that it's a guard against foreign
intervention on a process's credential state, such as is made by ptrace(). The
attachment of a debugger to a process affects execve()'s calculation of the new
credential state - _and_ also setprocattr()'s calculation of that state.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Don't check vm_region::vm_start is page aligned in add_nommu_region() because
the region may reflect some non-page-aligned mapped file, such as could be
obtained from RomFS XIP.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* 'for-linus' of git://neil.brown.name/md:
md: remove rd%d links immediately after stopping an array.
md: remove ability to explicit set an inactive array to 'clean'.
md: constify VFTs
md: tidy up status_resync to handle large arrays.
md: fix some (more) errors with bitmaps on devices larger than 2TB.
md/raid10: don't clear bitmap during recovery if array will still be degraded.
md: fix loading of out-of-date bitmap.
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md maintains link in sys/mdXX/md/ to identify which device has
which role in the array. e.g.
rd2 -> dev-sda
indicates that the device with role '2' in the array is sda.
These links are only present when the array is active. They are
created immediately after ->run is called, and so should be removed
immediately after ->stop is called.
However they are currently removed a little bit later, and it is
possible for ->run to be called again, thus adding these links, before
they are removed.
So move the removal earlier so they are consistently only present when
the array is active.
Signed-off-by: NeilBrown <neilb@suse.de>
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Being able to write 'clean' to an 'array_state' of an inactive array
to activate it in 'clean' mode is both unnecessary and inconvenient.
It is unnecessary because the same can be achieved by writing
'active'. This activates and array, but it still remains 'clean'
until the first write.
It is inconvenient because writing 'clean' is more often used to
cause an 'active' array to revert to 'clean' mode (thus blocking
any writes until a 'write-pending' is promoted to 'active').
Allowing 'clean' to both activate an array and mark an active array as
clean can lead to races: One program writes 'clean' to mark the
active array as clean at the same time as another program writes
'inactive' to deactivate (stop) and active array. Depending on which
writes first, the array could be deactivated and immediately
reactivated which isn't what was desired.
So just disable the use of 'clean' to activate an array.
This avoids a race that can be triggered with mdadm-3.0 and external
metadata, so it suitable for -stable.
Reported-by: Rafal Marszewski <rafal.marszewski@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
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Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: NeilBrown <neilb@suse.de>
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Two problems in status_resync.
1/ It still used Kilobytes as the basic block unit, while most code
now uses sectors uniformly.
2/ It doesn't allow for the possibility that max_sectors exceeds
the range of "unsigned long".
So
- change "max_blocks" to "max_sectors", and store sector numbers
in there and in 'resync'
- Make 'rt' a 'sector_t' so it can temporarily hold the number of
remaining sectors.
- use sector_div rather than normal division.
- change the magic '100' used to preserve precision to '32'.
+ making it a power of 2 makes division easier
+ it doesn't need to be as large as it was chosen when we averaged
speed over the entire run. Now we average speed over the last 30
seconds or so.
Reported-by: "Mario 'BitKoenig' Holbe" <Mario.Holbe@TU-Ilmenau.DE>
Signed-off-by: NeilBrown <neilb@suse.de>
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If a write intent bitmap covers more than 2TB, we sometimes work with
values beyond 32bit, so these need to be sector_t. This patches
add the required casts to some unsigned longs that are being shifted
up.
This will affect any raid10 larger than 2TB, or any raid1/4/5/6 with
member devices that are larger than 2TB.
Signed-off-by: NeilBrown <neilb@suse.de>
Reported-by: "Mario 'BitKoenig' Holbe" <Mario.Holbe@TU-Ilmenau.DE>
Cc: stable@kernel.org
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If we have a raid10 with multiple missing devices, and we recover just
one of these to a spare, then we risk (depending on the bitmap and
array chunk size) clearing bits of the bitmap for which recovery isn't
complete (because a device is still missing).
This can lead to a subsequent "re-add" being recovered without
any IO happening, which would result in loss of data.
This patch takes the safe approach of not clearing bitmap bits
if the array will still be degraded.
This patch is suitable for all active -stable kernels.
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
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When md is loading a bitmap which it knows is out of date, it fills
each page with 1s and writes it back out again. However the
write_page call makes used of bitmap->file_pages and
bitmap->last_page_size which haven't been set correctly yet. So this
can sometimes fail.
Move the setting of file_pages and last_page_size to before the call
to write_page.
This bug can cause the assembly on an array to fail, thus making the
data inaccessible. Hence I think it is a suitable candidate for
-stable.
Cc: stable@kernel.org
Reported-by: Vojtech Pavlik <vojtech@suse.cz>
Signed-off-by: NeilBrown <neilb@suse.de>
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It's a really simple patch that basically just open-codes the current
"secure_ip_id()" call, but when open-coding it we now use a _static_
hashing area, so that it gets updated every time.
And to make sure somebody can't just start from the same original seed of
all-zeroes, and then do the "half_md4_transform()" over and over until
they get the same sequence as the kernel has, each iteration also mixes in
the same old "current->pid + jiffies" we used - so we should now have a
regular strong pseudo-number generator, but we also have one that doesn't
have a single seed.
Note: the "pid + jiffies" is just meant to be a tiny tiny bit of noise. It
has no real meaning. It could be anything. I just picked the previous
seed, it's just that now we keep the state in between calls and that will
feed into the next result, and that should make all the difference.
I made that hash be a per-cpu data just to avoid cache-line ping-pong:
having multiple CPU's write to the same data would be fine for randomness,
and add yet another layer of chaos to it, but since get_random_int() is
supposed to be a fast interface I did it that way instead. I considered
using "__raw_get_cpu_var()" to avoid any preemption overhead while still
getting the hash be _mostly_ ping-pong free, but in the end good taste won
out.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] 5507/1: support R_ARM_MOVW_ABS_NC and MOVT_ABS relocation types
[ARM] 5506/1: davinci: DMA_32BIT_MASK --> DMA_BIT_MASK(32)
i.MX31: Disable CPU_32v6K in mx3_defconfig.
mx3fb: Fix compilation with CONFIG_PM
mx27ads: move PBC mapping out of vmalloc space
MXC: remove BUG_ON in interrupt handler
mx31: remove mx31moboard_defconfig
ARM: ARCH_MXC should select HAVE_CLK
mxc : BUG in imx_dma_request
mxc : Clean up properly when imx_dma_free() used without imx_dma_disable()
[ARM] mv78xx0: update defconfig
[ARM] orion5x: update defconfig
[ARM] Kirkwood: update defconfig
[ARM] Kconfig typo fix: "PXA930" -> "CPU_PXA930".
[ARM] S3C2412: Add missing cache flush in suspend code
[ARM] S3C: Add UDIVSLOT support for newer UARTS
[ARM] S3C64XX: Add S3C64XX_PA_IIS{0,1} to <mach/map.h>
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From: Bruce Ashfield <bruce.ashfield@windriver.com>
To fully support the armv7-a instruction set/optimizations, support
for the R_ARM_MOVW_ABS_NC and R_ARM_MOVT_ABS relocation types is
required.
The MOVW and MOVT are both load-immediate instructions, MOVW loads 16
bits into the bottom half of a register, and MOVT loads 16 bits into the
top half of a register.
The relocation information for these instructions has a full 32 bit
value, plus an addend which is stored in the 16 immediate bits in the
instruction itself. The immediate bits in the instruction are not
contiguous (the register # splits it into a 4 bit and 12 bit value),
so the addend has to be extracted accordingly and added to the value.
The value is then split and put into the instruction; a MOVW uses the
bottom 16 bits of the value, and a MOVT uses the top 16 bits.
Signed-off-by: David Borman <david.borman@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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As per commit 284901a90a9e0b812ca3f5f852cbbfb60d10249d, use
DMA_BIT_MASK(n)
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The i.MX31 ARM11 core is not a v6K core. Disable this option as it
is incompatible with non v6K cores.
Signed-off-by: Magnus Lilja <lilja.magnus@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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Before this patch I got the following line in my dmesg:
[ 0.000000] BUG: mapping for 0xd4000000 at 0xeb000000 overlaps vmalloc space
VMALLOC_END is 0xf4000000 and there are the following other mappings
defined for mx27ads:
(0xa0500000,+0x00001000) maps to 0xffff0000
(0x10000000,+0x00100000) maps to 0xf4000000
(0x80000000,+0x00100000) maps to 0xf4100000
(0xd8000000,+0x00100000) maps to 0xf4200000
So map PBC to 0xf4300000.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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On i.MX31 I sometimes get spurious interrupts. There is no need
to crash the whole system when this happens. Instead, silently
ignore it.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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We want to have a mx31_defconfig file that builds a kernel that is able
to boot on all support mx31 systems and thus also can be better tested
by automatic build scripts. For these reasons, this config file is not
needed anymore.
Signed-off-by: Valentin Longchamp <valentin.longchamp@epfl.ch>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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All i.MX platforms support <linux/clk.h> calls and should select HAVE_CLK.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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On MX2 platforms imx_dma_request() calls request_irq() which may sleep
with interrupts disabled.
Signed-off-by: Martin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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The sequence
imx_dma_request()
imx_dma_enable()
imx_dma_free()
left the dma channel in_use mode and did not release the timer.
Signed-off-by: Martin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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Signed-off-by: Nicolas Pitre <nico@marvell.com>
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Signed-off-by: Nicolas Pitre <nico@marvell.com>
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Signed-off-by: Nicolas Pitre <nico@marvell.com>
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Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The alterations to the suspend code missed adding a
call to the cache flushing routines during the suspend
path of the S3C2412.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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Add support for the UDIVSLOT register on the newer UART blocks
which gives the capability of 1/16ths adjustment to the baud rate.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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Add the physical address of the two I2S channel register blocks.
Signed-off-by: Ben Dooks <ben@simtec.co.uk>
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Fix zillions of -mm x86_64 allmodconfig build errors - the file uses
EXPORT_SYMBOL() and kmalloc but misses the needed includes.
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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With the removal of duplicate unpack_to_rootfs() (commit
df52092f3c97788592ef72501a43fb7ac6a3cfe0) the messages displayed do not
actually correspond to what the kernel is doing. In addition, depending
if ramdisks are supported or not, the messages are not at all the same.
So keep the messages more in sync with what is really doing the kernel,
and only display a second message in case of failure. This also ensure
that the printk message cannot be split by other printk's.
Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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NOMMU mmap() has an option controlled by a sysctl variable that determines
whether the allocations made by do_mmap_private() should have the excess
space trimmed off and returned to the allocator. Make the initial setting
of this variable a Kconfig configuration option.
The reason there can be excess space is that the allocator only allocates
in power-of-2 size chunks, but mmap()'s can be made in sizes that aren't a
power of 2.
There are two alternatives:
(1) Keep the excess as dead space. The dead space then remains unused for the
lifetime of the mapping. Mappings of shared objects such as libc, ld.so
or busybox's text segment may retain their dead space forever.
(2) Return the excess to the allocator. This means that the dead space is
limited to less than a page per mapping, but it means that for a transient
process, there's more chance of fragmentation as the excess space may be
reused fairly quickly.
During the boot process, a lot of transient processes are created, and
this can cause a lot of fragmentation as the pagecache and various slabs
grow greatly during this time.
By turning off the trimming of excess space during boot and disabling
batching of frees, Coldfire can manage to boot.
A better way of doing things might be to have /sbin/init turn this option
off. By that point libc, ld.so and init - which are all long-duration
processes - have all been loaded and trimmed.
Reported-by: Lanttor Guo <lanttor.guo@freescale.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Lanttor Guo <lanttor.guo@freescale.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Clamp zone_batchsize() to 0 under NOMMU conditions to stop
free_hot_cold_page() from queueing and batching frees.
The problem is that under NOMMU conditions it is really important to be
able to allocate large contiguous chunks of memory, but when munmap() or
exit_mmap() releases big stretches of memory, return of these to the buddy
allocator can be deferred, and when it does finally happen, it can be in
small chunks.
Whilst the fragmentation this incurs isn't so much of a problem under MMU
conditions as userspace VM is glued together from individual pages with
the aid of the MMU, it is a real problem if there isn't an MMU.
By clamping the page freeing queue size to 0, pages are returned to the
allocator immediately, and the buddy detector is more likely to be able to
glue them together into large chunks immediately, and fragmentation is
less likely to occur.
By disabling batching of frees, and by turning off the trimming of excess
space during boot, Coldfire can manage to boot.
Reported-by: Lanttor Guo <lanttor.guo@freescale.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Lanttor Guo <lanttor.guo@freescale.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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