linux-toradex.git/Documentation, branch v2.6.33.9 Linux kernel for Apalis and Colibri modules i2c: Fix typo in instantiating-devices document 2011-03-28T14:31:18+00:00 Roman Fietze roman.fietze@telemotive.de 2011-03-20T13:50:52+00:00 d94f53b9b054b9fd0e783323eaa0f53cc84a232c commit 6ced9e6b3901af4ab6ac0a11231402c888286ea6 upstream. The struct i2c_board_info member holding the name is "type", not "name". Signed-off-by: Roman Fietze <roman.fietze@telemotive.de> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 6ced9e6b3901af4ab6ac0a11231402c888286ea6 upstream.

The struct i2c_board_info member holding the name is "type", not
"name".

Signed-off-by: Roman Fietze <roman.fietze@telemotive.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
hwmon: (ltc4245) Read only one GPIO pin 2010-07-05T18:15:55+00:00 Ira W. Snyder iws@ovro.caltech.edu 2010-05-27T17:59:02+00:00 91fe12f532fc6687218f4861f0ac7b7ded419383 commit df16dd53c575d0cb9dbee20a3149927c862a9ff6 upstream. Read only one of the GPIO pins as an analog voltage. The ADC can be switched to a different GPIO pin at runtime, but this is not supported. Previously, this driver would report the analog voltage of the currently selected GPIO pin as all three GPIO voltages: in9_input, in10_input and in11_input. Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit df16dd53c575d0cb9dbee20a3149927c862a9ff6 upstream.

Read only one of the GPIO pins as an analog voltage. The ADC can be
switched to a different GPIO pin at runtime, but this is not supported.

Previously, this driver would report the analog voltage of the currently
selected GPIO pin as all three GPIO voltages: in9_input, in10_input and
in11_input.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
revert "procfs: provide stack information for threads" and its fixup commits 2010-05-26T21:32:04+00:00 Robin Holt holt@sgi.com 2010-05-11T21:06:46+00:00 b759d0992e1fdcf2a76ebef37289e787b375fa28 commit 34441427aab4bdb3069a4ffcda69a99357abcb2e upstream. Originally, commit d899bf7b ("procfs: provide stack information for threads") attempted to introduce a new feature for showing where the threadstack was located and how many pages are being utilized by the stack. Commit c44972f1 ("procfs: disable per-task stack usage on NOMMU") was applied to fix the NO_MMU case. Commit 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on 64-bit") was applied to fix a bug in ia32 executables being loaded. Commit 9ebd4eba7 ("procfs: fix /proc/<pid>/stat stack pointer for kernel threads") was applied to fix a bug which had kernel threads printing a userland stack address. Commit 1306d603f ('proc: partially revert "procfs: provide stack information for threads"') was then applied to revert the stack pages being used to solve a significant performance regression. This patch nearly undoes the effect of all these patches. The reason for reverting these is it provides an unusable value in field 28. For x86_64, a fork will result in the task->stack_start value being updated to the current user top of stack and not the stack start address. This unpredictability of the stack_start value makes it worthless. That includes the intended use of showing how much stack space a thread has. Other architectures will get different values. As an example, ia64 gets 0. The do_fork() and copy_process() functions appear to treat the stack_start and stack_size parameters as architecture specific. I only partially reverted c44972f1 ("procfs: disable per-task stack usage on NOMMU") . If I had completely reverted it, I would have had to change mm/Makefile only build pagewalk.o when CONFIG_PROC_PAGE_MONITOR is configured. Since I could not test the builds without significant effort, I decided to not change mm/Makefile. I only partially reverted 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on 64-bit") . I left the KSTK_ESP() change in place as that seemed worthwhile. Signed-off-by: Robin Holt <holt@sgi.com> Cc: Stefani Seibold <stefani@seibold.net> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 34441427aab4bdb3069a4ffcda69a99357abcb2e upstream.

Originally, commit d899bf7b ("procfs: provide stack information for
threads") attempted to introduce a new feature for showing where the
threadstack was located and how many pages are being utilized by the
stack.

Commit c44972f1 ("procfs: disable per-task stack usage on NOMMU") was
applied to fix the NO_MMU case.

Commit 89240ba0 ("x86, fs: Fix x86 procfs stack information for threads on
64-bit") was applied to fix a bug in ia32 executables being loaded.

Commit 9ebd4eba7 ("procfs: fix /proc/<pid>/stat stack pointer for kernel
threads") was applied to fix a bug which had kernel threads printing a
userland stack address.

Commit 1306d603f ('proc: partially revert "procfs: provide stack
information for threads"') was then applied to revert the stack pages
being used to solve a significant performance regression.

This patch nearly undoes the effect of all these patches.

The reason for reverting these is it provides an unusable value in
field 28.  For x86_64, a fork will result in the task->stack_start
value being updated to the current user top of stack and not the stack
start address.  This unpredictability of the stack_start value makes
it worthless.  That includes the intended use of showing how much stack
space a thread has.

Other architectures will get different values.  As an example, ia64
gets 0.  The do_fork() and copy_process() functions appear to treat the
stack_start and stack_size parameters as architecture specific.

I only partially reverted c44972f1 ("procfs: disable per-task stack usage
on NOMMU") .  If I had completely reverted it, I would have had to change
mm/Makefile only build pagewalk.o when CONFIG_PROC_PAGE_MONITOR is
configured.  Since I could not test the builds without significant effort,
I decided to not change mm/Makefile.

I only partially reverted 89240ba0 ("x86, fs: Fix x86 procfs stack
information for threads on 64-bit") .  I left the KSTK_ESP() change in
place as that seemed worthwhile.

Signed-off-by: Robin Holt <holt@sgi.com>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c-i801: Add Intel Cougar Point device IDs 2010-04-26T14:48:00+00:00 Seth Heasley seth.heasley@intel.com 2010-03-02T11:23:39+00:00 faab88ee678576f5280517c54a5ecbd67a64fadc commit 393764340beb595c1ad7dd2d2243c2b6551aaa71 upstream. Add the Intel Cougar Point (PCH) SMBus controller device IDs. Signed-off-by: Seth Heasley <seth.heasley@intel.com> Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: maximilian attems <max@stro.at> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 393764340beb595c1ad7dd2d2243c2b6551aaa71 upstream.

Add the Intel Cougar Point (PCH) SMBus controller device IDs.

Signed-off-by: Seth Heasley <seth.heasley@intel.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: maximilian attems <max@stro.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
doc: add the documentation for mpol=local 2010-04-01T23:01:32+00:00 KOSAKI Motohiro kosaki.motohiro@jp.fujitsu.com 2010-03-23T20:35:33+00:00 82df18799be6189a905651888ea471ef11e01807 commit 5574169613b40b85d6f4c67208fa4846b897a0a1 upstream. commit 3f226aa1c (mempolicy: support mpol=local tmpfs mount option) added new mpol=local mount option. but it didn't add a documentation. This patch does it. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Ravikiran Thirumalai <kiran@scalex86.org> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Mel Gorman <mel@csn.ul.ie> Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 5574169613b40b85d6f4c67208fa4846b897a0a1 upstream.

commit 3f226aa1c (mempolicy: support mpol=local tmpfs mount option) added
new mpol=local mount option.  but it didn't add a documentation.

This patch does it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
x86, mm: Allow highmem user page tables to be disabled at boot time 2010-03-15T16:07:14+00:00 Ian Campbell ian.campbell@citrix.com 2010-02-17T10:38:10+00:00 4f92d68b5499675b5c90d8491aaeea0b10ec97f7 commit 14315592009c17035cac81f4954d5a1f4d71e489 upstream. Distros generally (I looked at Debian, RHEL5 and SLES11) seem to enable CONFIG_HIGHPTE for any x86 configuration which has highmem enabled. This means that the overhead applies even to machines which have a fairly modest amount of high memory and which therefore do not really benefit from allocating PTEs in high memory but still pay the price of the additional mapping operations. Running kernbench on a 4G box I found that with CONFIG_HIGHPTE=y but no actual highptes being allocated there was a reduction in system time used from 59.737s to 55.9s. With CONFIG_HIGHPTE=y and highmem PTEs being allocated: Average Optimal load -j 4 Run (std deviation): Elapsed Time 175.396 (0.238914) User Time 515.983 (5.85019) System Time 59.737 (1.26727) Percent CPU 263.8 (71.6796) Context Switches 39989.7 (4672.64) Sleeps 42617.7 (246.307) With CONFIG_HIGHPTE=y but with no highmem PTEs being allocated: Average Optimal load -j 4 Run (std deviation): Elapsed Time 174.278 (0.831968) User Time 515.659 (6.07012) System Time 55.9 (1.07799) Percent CPU 263.8 (71.266) Context Switches 39929.6 (4485.13) Sleeps 42583.7 (373.039) This patch allows the user to control the allocation of PTEs in highmem from the command line ("userpte=nohigh") but retains the status-quo as the default. It is possible that some simple heuristic could be developed which allows auto-tuning of this option however I don't have a sufficiently large machine available to me to perform any particularly meaningful experiments. We could probably handwave up an argument for a threshold at 16G of total RAM. Assuming 768M of lowmem we have 196608 potential lowmem PTE pages. Each page can map 2M of RAM in a PAE-enabled configuration, meaning a maximum of 384G of RAM could potentially be mapped using lowmem PTEs. Even allowing generous factor of 10 to account for other required lowmem allocations, generous slop to account for page sharing (which reduces the total amount of RAM mappable by a given number of PT pages) and other innacuracies in the estimations it would seem that even a 32G machine would not have a particularly pressing need for highmem PTEs. I think 32G could be considered to be at the upper bound of what might be sensible on a 32 bit machine (although I think in practice 64G is still supported). It's seems questionable if HIGHPTE is even a win for any amount of RAM you would sensibly run a 32 bit kernel on rather than going 64 bit. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> LKML-Reference: <1266403090-20162-1-git-send-email-ian.campbell@citrix.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 14315592009c17035cac81f4954d5a1f4d71e489 upstream.

Distros generally (I looked at Debian, RHEL5 and SLES11) seem to
enable CONFIG_HIGHPTE for any x86 configuration which has highmem
enabled. This means that the overhead applies even to machines which
have a fairly modest amount of high memory and which therefore do not
really benefit from allocating PTEs in high memory but still pay the
price of the additional mapping operations.

Running kernbench on a 4G box I found that with CONFIG_HIGHPTE=y but
no actual highptes being allocated there was a reduction in system
time used from 59.737s to 55.9s.

With CONFIG_HIGHPTE=y and highmem PTEs being allocated:
  Average Optimal load -j 4 Run (std deviation):
  Elapsed Time 175.396 (0.238914)
  User Time 515.983 (5.85019)
  System Time 59.737 (1.26727)
  Percent CPU 263.8 (71.6796)
  Context Switches 39989.7 (4672.64)
  Sleeps 42617.7 (246.307)

With CONFIG_HIGHPTE=y but with no highmem PTEs being allocated:
  Average Optimal load -j 4 Run (std deviation):
  Elapsed Time 174.278 (0.831968)
  User Time 515.659 (6.07012)
  System Time 55.9 (1.07799)
  Percent CPU 263.8 (71.266)
  Context Switches 39929.6 (4485.13)
  Sleeps 42583.7 (373.039)

This patch allows the user to control the allocation of PTEs in
highmem from the command line ("userpte=nohigh") but retains the
status-quo as the default.

It is possible that some simple heuristic could be developed which
allows auto-tuning of this option however I don't have a sufficiently
large machine available to me to perform any particularly meaningful
experiments. We could probably handwave up an argument for a threshold
at 16G of total RAM.

Assuming 768M of lowmem we have 196608 potential lowmem PTE
pages. Each page can map 2M of RAM in a PAE-enabled configuration,
meaning a maximum of 384G of RAM could potentially be mapped using
lowmem PTEs.

Even allowing generous factor of 10 to account for other required
lowmem allocations, generous slop to account for page sharing (which
reduces the total amount of RAM mappable by a given number of PT
pages) and other innacuracies in the estimations it would seem that
even a 32G machine would not have a particularly pressing need for
highmem PTEs. I think 32G could be considered to be at the upper bound
of what might be sensible on a 32 bit machine (although I think in
practice 64G is still supported).

It's seems questionable if HIGHPTE is even a win for any amount of RAM
you would sensibly run a 32 bit kernel on rather than going 64 bit.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
LKML-Reference: <1266403090-20162-1-git-send-email-ian.campbell@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
thinkpad-acpi: lock down video output state access 2010-03-15T16:06:48+00:00 Henrique de Moraes Holschuh hmh@hmh.eng.br 2010-02-26T01:22:22+00:00 c9438d3d949d4c5f88f630b647011b8381c63ae5 commit b525c06cdbd8a3963f0173ccd23f9147d4c384b5 upstream. Given the right combination of ThinkPad and X.org, just reading the video output control state is enough to hard-crash X.org. Until the day I somehow find out a model or BIOS cut date to not provide this feature to ThinkPads that can do video switching through X RandR, change permissions so that only processes with CAP_SYS_ADMIN can access any sort of video output control state. This bug could be considered a local DoS I suppose, as it allows any non-privledged local user to cause some versions of X.org to hard-crash some ThinkPads. Reported-by: Jidanni <jidanni@jidanni.org> Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit b525c06cdbd8a3963f0173ccd23f9147d4c384b5 upstream.

Given the right combination of ThinkPad and X.org, just reading the
video output control state is enough to hard-crash X.org.

Until the day I somehow find out a model or BIOS cut date to not
provide this feature to ThinkPads that can do video switching through
X RandR, change permissions so that only processes with CAP_SYS_ADMIN
can access any sort of video output control state.

This bug could be considered a local DoS I suppose, as it allows any
non-privledged local user to cause some versions of X.org to
hard-crash some ThinkPads.

Reported-by: Jidanni <jidanni@jidanni.org>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-02-24T03:44:07+00:00 Linus Torvalds torvalds@linux-foundation.org 2010-02-24T03:44:07+00:00 75ef7cdda2daa35be9e070ac8e5258759ac03d06 * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: net: bug fix for vlan + gro issue tc35815: Remove a wrong netif_wake_queue() call which triggers BUG_ON cdc_ether: new PID for Ericsson C3607w to the whitelist (resubmit) IPv6: better document max_addresses parameter MAINTAINERS: update mv643xx_eth maintenance status e1000: Fix DMA mapping error handling on RX iwlwifi: sanity check before counting number of tfds can be free iwlwifi: error checking for number of tfds in queue iwlwifi: set HT flags after channel in rxon 
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  net: bug fix for vlan + gro issue
  tc35815: Remove a wrong netif_wake_queue() call which triggers BUG_ON
  cdc_ether: new PID for Ericsson C3607w to the whitelist (resubmit)
  IPv6: better document max_addresses parameter
  MAINTAINERS: update mv643xx_eth maintenance status
  e1000: Fix DMA mapping error handling on RX
  iwlwifi: sanity check before counting number of tfds can be free
  iwlwifi: error checking for number of tfds in queue
  iwlwifi: set HT flags after channel in rxon
IPv6: better document max_addresses parameter 2010-02-23T09:25:00+00:00 Brian Haley brian.haley@hp.com 2010-02-22T12:27:21+00:00 e79dc48431e7731f5bb6bab8f6b499fe03802ca0 Andrew Morton wrote: >> >From ip-sysctl.txt file in kernel documentation I can see following description >> for max_addresses: >> max_addresses - INTEGER >> Number of maximum addresses per interface. 0 disables limitation. >> It is recommended not set too large value (or 0) because it would >> be too easy way to crash kernel to allow to create too much of >> autoconfigured addresses. ^^^^^^^^^^^^^^ >> If this parameter applies only for auto-configured IP addressed, please state >> it more clearly in docs or rename the parameter to show that it refers to >> auto-configuration. It did mention autoconfigured in the text, but the below makes it more obvious. More clearly document IPv6 max_addresses parameter. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Andrew Morton wrote:
>> >From ip-sysctl.txt file in kernel documentation I can see following description
>> for max_addresses:
>> max_addresses - INTEGER
>>         Number of maximum addresses per interface.  0 disables limitation.
>>         It is recommended not set too large value (or 0) because it would
>>         be too easy way to crash kernel to allow to create too much of
>>         autoconfigured addresses.
           ^^^^^^^^^^^^^^

>> If this parameter applies only for auto-configured IP addressed, please state
>> it more clearly in docs or rename the parameter to show that it refers to
>> auto-configuration.

It did mention autoconfigured in the text, but the below makes it more obvious.

More clearly document IPv6 max_addresses parameter.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ARM: allow alignment fault mode to be configured at kernel boot 2010-02-20T16:20:49+00:00 Russell King rmk+kernel@arm.linux.org.uk 2010-02-20T16:13:29+00:00 d944d549aa86e08cba080396513234cf048fee1f Some glibc versions intentionally create lots of alignment faults in their gconv code, which if not fixed up, results in segfaults during boot. This can prevent systems booting properly. There is no clear hard-configurable default for this; the desired default depends on the nature of the userspace which is going to be booted. So, provide a way for the alignment fault handler to be configured via the kernel command line. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Some glibc versions intentionally create lots of alignment faults in
their gconv code, which if not fixed up, results in segfaults during
boot.  This can prevent systems booting properly.

There is no clear hard-configurable default for this; the desired
default depends on the nature of the userspace which is going to be
booted.

So, provide a way for the alignment fault handler to be configured via
the kernel command line.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>