kmemtrace provides tracing for slab allocator functions, such as kmalloc,
kfree, kmem_cache_alloc, kmem_cache_free etc.. Collected data is then fed
to the userspace application in order to analyse allocation hotspots,
internal fragmentation and so on, making it possible to see how well an
allocator performs, as well as debug and profile kernel code.
Signed-off-by: NEduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>

kunmap() takes as argument the struct page that orginally got kmap()'d,
however the sg_miter_stop() function passed it the kernel virtual address
instead, resulting in weird stuff.

Somehow I ended up fixing this bug by accident while looking for a bug in
the same area.

Reported-by: kerneloops.org
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>		[2.6.27.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Impact: fix DMA buffer allocation coherency bug in certain configs

This patch fixes swiotlb to use dev->coherent_dma_mask in
swiotlb_alloc_coherent().

coherent_dma_mask is a subset of dma_mask (equal to it most of
the time), enumerating the address range that a given device
is able to DMA to/from in a cache-coherent way.

But currently, swiotlb uses dev->dma_mask in alloc_coherent()
implicitly via address_needs_mapping(), but alloc_coherent is really
supposed to use coherent_dma_mask.

This bug could break drivers that uses smaller coherent_dma_mask than
dma_mask (though the current code works for the majority that use the
same mask for coherent_dma_mask and dma_mask).
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: tony.luck@intel.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

Clean up based on feedback from Andrew Morton and others:

 - change to inline functions instead of macros
 - add __init to bootmem method
 - add a missing debug check
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

- add cpumask_of()
- add free_bootmem_cpumask_var()
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: introduce new APIs

We want to deprecate cpumasks on the stack, as we are headed for
gynormous numbers of CPUs.  Eventually, we want to head towards an
undefined 'struct cpumask' so they can never be declared on stack.

1) New cpumask functions which take pointers instead of copies.
   (cpus_* -> cpumask_*)

2) Several new helpers to reduce requirements for temporary cpumasks
   (cpumask_first_and, cpumask_next_and, cpumask_any_and)

3) Helpers for declaring cpumasks on or offstack for large NR_CPUS
   (cpumask_var_t, alloc_cpumask_var and free_cpumask_var)

4) 'struct cpumask' for explicitness and to mark new-style code.

5) Make iterator functions stop at nr_cpu_ids (a runtime constant),
   not NR_CPUS for time efficiency and for smaller dynamic allocations
   in future.

6) cpumask_copy() so we can allocate less than a full cpumask eventually
   (for alloc_cpumask_var), and so we can eliminate the 'struct cpumask'
   definition eventually.

7) work_on_cpu() helper for doing task on a CPU, rather than saving old
   cpumask for current thread and manipulating it.

8) smp_call_function_many() which is smp_call_function_mask() except
   taking a cpumask pointer.

Note that this patch simply introduces the new functions and leaves
the obsolescent ones in place.  This is to simplify the transition
patches.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In testing 2.6.28-rc1, I found that passing 'dynamic_printk' on the command
line didn't activate the debug code. The problem is that dynamic_printk_setup()
(which activates the debugging) is being called before dynamic_printk_init() is
called (which initializes infrastructure). Fix this by setting setting the
state to 'DYNAMIC_ENABLED_ALL' in dynamic_printk_setup(), which will also
cause all subsequent modules to have debugging automatically started, which is
probably the behavior we want.
Signed-off-by: NJason Baron <jbaron@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

swiotlb_alloc_coherent calls panic() when allocated swiotlb pages is
not fit for a device's dma mask. However, alloc_coherent failure is
not a disaster at all. AFAIK, none of other x86 and IA64 IOMMU
implementations don't crash in case of alloc_coherent failure.

There are some drivers that don't check alloc_coherent failure but not
many (about ten and I've already started to fix some of
them). alloc_coherent returns NULL in case of failure so it's likely
that these guilty drivers crash immediately. So swiotlb doesn't need
to call panic() just for them.
Reported-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We would hang forever when passing a zero to string_get_size().
Furthermore, string_get_size() would produce decimals on a value small
enough to be exact.  Finally, a few formatting issues are inconsistent
with standard SI style guidelines.

- If the value is less than the divisor, skip the entire rounding
  step.  This prints out all small values including zero as integers,
  without decimals.
- Add a space between the value and the symbol for the unit,
  consistent with standard SI practice.
- Lower case k in kB since we are talking about powers of 10.
- Finally, change "int" to "unsigned int" in one place to shut up a
  gcc warning when compiling the code out-of-kernel for testing.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER.  The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.

This patch was generated mostly by script, and partially by hand.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add a %pR option to the kernel vsnprintf that prints the range of
addresses inside a struct resource passed by pointer.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

bitmap_scnprintf_len() is not used now, so we remove it.

Otherwise we have to maintain it and make its return
value always equal to bitmap_scnprintf()'s return value.
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

CONFIG_DEBUG_BLOCK_EXT_DEVT can break booting even on some modern
distros.  Add BIG FAT WARNING to keep people at a safe distance.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Open-code them rather than using defining macros.  The function bodies are now
next to their kerneldoc comments as a bonus.

Add casts to the signed cases as they call into the unsigned versions.

Avoids the sparse warnings:
lib/vsprintf.c:249:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:249:1:    expected unsigned long *res
lib/vsprintf.c:249:1:    got long *res
lib/vsprintf.c:249:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:249:1:    expected unsigned long *res
lib/vsprintf.c:249:1:    got long *res
lib/vsprintf.c:251:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:251:1:    expected unsigned long long *res
lib/vsprintf.c:251:1:    got long long *res
lib/vsprintf.c:251:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:251:1:    expected unsigned long long *res
lib/vsprintf.c:251:1:    got long long *res
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove extra lines before the EXPORT_SYMBOL()s
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The default base is 10 unless there is a leading zero, in which
case the base will be guessed as 8.

The base will only be guesed as 16 when the string starts with '0x'
the third character is a valid hex digit.
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch introduces the generic iommu_num_pages function. It can be used by
a given memory area.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add documentation in kerneldoc for new printk format extensions

This patch documents the new %pS/%pF options in printk in kernel doc.

Hope I didn't miss any other extension.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using "def_bool n" is pointless, simply using bool here appears more
appropriate.

Further, retaining such options that don't have a prompt and aren't
selected by anything seems also at least questionable.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add documentation in kerneldoc for new printk format extensions

This patch documents the new %pS/%pF options in printk in kernel doc.

Hope I didn't miss any other extension.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

It finally dawned on me what the clean fix to sysfs_rename_dir
calling kobject_set_name is.  Move the work into kobject_rename
where it belongs.  The callers serialize us anyway so this is
safe.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When looking at kobject_rename I found two bugs with
that exist when sysfs support is disabled in the kernel.

kobject_rename does not change the name on the kobject when
sysfs support is not compiled in.

kobject_rename without locking attempts to check the
validity of a rename operation, which the kobject layer
simply does not have the infrastructure to do.

This patch documents the previously unstated requirement of
kobject_rename that is the responsibility of the caller to
provide mutual exclusion and to be certain that the new_name
for the kobject is valid.

This patch modifies sysfs_rename_dir in !CONFIG_SYSFS case
to call kobject_set_name to actually change the kobject_name.

This patch removes the bogus and misleading check in kobject_rename
that attempts to see if a rename is valid.  The check is bogus
because we do not have the proper locking.  The check is misleading
because it looks like we can and do perform checking at the kobject
level that we don't.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Base infrastructure to enable per-module debug messages.

I've introduced CONFIG_DYNAMIC_PRINTK_DEBUG, which when enabled centralizes
control of debugging statements on a per-module basis in one /proc file,
currently, <debugfs>/dynamic_printk/modules. When, CONFIG_DYNAMIC_PRINTK_DEBUG,
is not set, debugging statements can still be enabled as before, often by
defining 'DEBUG' for the proper compilation unit. Thus, this patch set has no
affect when CONFIG_DYNAMIC_PRINTK_DEBUG is not set.

The infrastructure currently ties into all pr_debug() and dev_dbg() calls. That
is, if CONFIG_DYNAMIC_PRINTK_DEBUG is set, all pr_debug() and dev_dbg() calls
can be dynamically enabled/disabled on a per-module basis.

Future plans include extending this functionality to subsystems, that define 
their own debug levels and flags.

Usage:

Dynamic debugging is controlled by the debugfs file, 
<debugfs>/dynamic_printk/modules. This file contains a list of the modules that
can be enabled. The format of the file is as follows:

	<module_name> <enabled=0/1>
		.
		.
		.

	<module_name> : Name of the module in which the debug call resides
	<enabled=0/1> : whether the messages are enabled or not

For example:

	snd_hda_intel enabled=0
	fixup enabled=1
	driver enabled=0

Enable a module:

	$echo "set enabled=1 <module_name>" > dynamic_printk/modules

Disable a module:

	$echo "set enabled=0 <module_name>" > dynamic_printk/modules

Enable all modules:

	$echo "set enabled=1 all" > dynamic_printk/modules

Disable all modules:

	$echo "set enabled=0 all" > dynamic_printk/modules

Finally, passing "dynamic_printk" at the command line enables
debugging for all modules. This mode can be turned off via the above
disable command.

[gkh: minor cleanups and tweaks to make the build work quietly]
Signed-off-by: NJason Baron <jbaron@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.

This was posted for review some time ago and I believe its been in -mm
since then.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Only works for the generic request timer handling. Allows one to
sporadically ignore request completions, thus exercising the timeout
handling.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

DEBUG_BLOCK_EXT_DEVT shuffles SCSI and IDE device numbers and root
device number set using rdev become meaningless.  Root devices should
be explicitly specified using textual names.  Warn about it if root
can't be found and DEBUG_BLOCK_EXT_DEVT is enabled.  Also, add warning
to the help text.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

It's a debug option that you would explicitly enable to test this
feature, we should default it to 'n' to prevent accidental surprises
for now.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Extended devt introduces non-contiguos device numbers.  This patch
implements a debug option which forces most devt allocations to be
from the extended area and spreads them out.  This is enabled by
default if DEBUG_KERNEL is set and achieves...

1. Detects code paths in kernel or userland which expect predetermined
   consecutive device numbers.

2. When something goes wrong, avoid corruption as adding to the minor
   of earlier partition won't lead to the wrong but valid device.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

A klist entry is kept on the list till all its current iterations are
finished; however, a new iteration after deletion also iterates over
deleted entries as long as their reference count stays above zero.
This causes problems for cases where there are users which iterate
over the list while synchronized against list manipulations and
natuarally expect already deleted entries to not show up during
iteration.

This patch implements dead flag which gets set on deletion so that
iteration can skip already deleted entries.  The dead flag piggy backs
on the lowest bit of knode->n_klist and only visible to klist
implementation proper.

While at it, drop klist_iter->i_head as it's redundant and doesn't
offer anything in semantics or performance wise as klist_iter->i_klist
is dereferenced on every iteration anyway.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This patch adds the ability to print sizes in either units of 10^3 (SI)
or 2^10 (Binary) units.  It rounds up to three significant figures and
can be used for either memory or storage capacities.

Oh, and I'm fully aware that 64 bits is only 16EiB ... the Zetta and
Yotta units are added for future proofing against the day we have 128
bit computers ...

[fujita.tomonori@lab.ntt.co.jp: fix missed unsigned long long cast]
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

This patch adds stalled-CPU detection to Classic RCU.  This capability
is enabled by a new config variable CONFIG_RCU_CPU_STALL_DETECTOR, which
defaults disabled.

This is a debugging feature to detect infinite loops in kernel code, not
something that non-kernel-hackers would be expected to care about.

This feature can detect looping CPUs in !PREEMPT builds and looping CPUs
with preemption disabled in PREEMPT builds.  This is essentially a port of
this functionality from the treercu patch, replacing the stall debug patch
that is already in tip/core/rcu (commit 67182ae1).

The changes from the patch in tip/core/rcu include making the config
variable name match that in treercu, changing from seconds to jiffies to
avoid spurious warnings, and printing a boot message when this feature
is enabled.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

x86 has set_bit_string() that does the exact same thing that
set_bit_area() in lib/iommu-helper.c does.

This patch exports set_bit_area() in lib/iommu-helper.c as
iommu_area_reserve(), converts GART, Calgary, and AMD IOMMU to use it.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

swiotlb can use dma_get_mask() instead of the homegrown function.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: tony.luck@intel.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

bitmap_copy_le() copies a bitmap, putting the bits into little-endian
order (i.e., each unsigned long word in the bitmap is put into
little-endian order).

The UWB stack used bitmaps to manage Medium Access Slot availability,
and these bitmaps need to be written to the hardware in LE order.
Signed-off-by: NDavid Vrabel <david.vrabel@csr.com>

The callers of sg_copy_buffer must disable interrupts before calling
it (since it uses kmap_atomic). Some callers use it on
interrupt-disabled code but some need to take the trouble to disable
interrupts just for this. No wonder they forget about it and we hit a
bug like:

http://bugzilla.kernel.org/show_bug.cgi?id=11529

James said that it might be better to disable interrupts inside the
function rather than risk the callers getting it wrong.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This fixes a SWIOTLB oops

With SWIOTLB being enabled and straight-forward page allocation
failure [1], the swiotlb_alloc_coherent fall-back path hits an
issue [2], resulting in my webcam failing to work.

At the time of oops, RDI is clearly a pointer to a structure which
has arrived as NULL, leading to the typo in swiotlb_map_single's
callsite arguments.

Correctly passing the device structure [3] addresses the issue and
gets my webcam working again (the allocation failure still occuring).

 --- [1]

skype: page allocation failure. order:3, mode:0x1
Pid: 5895, comm: skype Not tainted 2.6.27-rc6-235c-debug #1

Call Trace:
 [<ffffffff802b7cf0>] __alloc_pages_internal+0x4a0/0x5d0
 [<ffffffff802d5ddd>] alloc_pages_current+0xad/0x110
 [<ffffffff802b4ccd>] __get_free_pages+0x1d/0x60
 [<ffffffff8046cd39>] swiotlb_alloc_coherent+0x49/0x180
 [<ffffffff80212731>] dma_alloc_coherent+0x281/0x310
 [<ffffffff805621c0>] hcd_buffer_alloc+0x50/0x90
 [<ffffffff805547fd>] usb_buffer_alloc+0x2d/0x40
 [<ffffffffa0056763>] uvc_alloc_urb_buffers+0x53/0xf0 [uvcvideo]
 [<ffffffffa0056958>] uvc_init_video+0x158/0x3e0 [uvcvideo]
 [<ffffffffa0056c17>] uvc_video_enable+0x37/0x80 [uvcvideo]
 [<ffffffffa0055853>] uvc_v4l2_do_ioctl+0x723/0x1260 [uvcvideo]
 [<ffffffff8026dd61>] ? trace_hardirqs_off_caller+0x21/0xc0
 [<ffffffff8026dd61>] ? trace_hardirqs_off_caller+0x21/0xc0
 [<ffffffffa0032c9f>] video_usercopy+0x19f/0x390 [videodev]
 [<ffffffffa0055130>] ? uvc_v4l2_do_ioctl+0x0/0x1260 [uvcvideo]
 [<ffffffff8026d0ce>] ? put_lock_stats+0xe/0x30
 [<ffffffffa0054dad>] uvc_v4l2_ioctl+0x4d/0x80 [uvcvideo]
 [<ffffffffa0045083>] native_ioctl+0x83/0x90 [compat_ioctl32]
 [<ffffffffa004534e>] v4l_compat_ioctl32+0x2be/0x1da4 [compat_ioctl32]
 [<ffffffff806aad21>] ? do_page_fault+0x3d1/0xae0
 [<ffffffff80270ccd>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff80270c59>] ? trace_hardirqs_on_caller+0x149/0x1b0
 [<ffffffff80270ccd>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff80329afa>] compat_sys_ioctl+0x8a/0x3c0
 [<ffffffff806a700d>] ? trace_hardirqs_off_thunk+0x3a/0x3c
 [<ffffffff8022f816>] sysenter_dispatch+0x7/0x2c
 [<ffffffff806a6fce>] ? trace_hardirqs_on_thunk+0x3a/0x3f

Mem-Info:
Node 0 DMA per-cpu:
CPU    0: hi:    0, btch:   1 usd:   0
CPU    1: hi:    0, btch:   1 usd:   0
Node 0 DMA32 per-cpu:
CPU    0: hi:  186, btch:  31 usd:   3
CPU    1: hi:  186, btch:  31 usd:   0
Node 0 Normal per-cpu:
CPU    0: hi:  186, btch:  31 usd:  23
CPU    1: hi:  186, btch:  31 usd: 179
Active:78545 inactive:48683 dirty:31 writeback:0 unstable:2
 free:830202 slab:17516 mapped:17473 pagetables:3496 bounce:0
Node 0 DMA free:36kB min:28kB low:32kB high:40kB active:0kB
inactive:0kB present:15156kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 3207 3956 3956
Node 0 DMA32 free:3197192kB min:6512kB low:8140kB high:9768kB
active:0kB inactive:0kB present:3284896kB pages_scanned:0
all_unreclaimable? no
lowmem_reserve[]: 0 0 748 748
Node 0 Normal free:123580kB min:1516kB low:1892kB high:2272kB
active:314180kB inactive:194732kB present:766464kB pages_scanned:0
all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 0 DMA: 1*4kB 0*8kB 0*16kB 1*32kB 0*64kB 0*128kB 0*256kB 0*512kB
0*1024kB 0*2048kB 0*4096kB = 36kB
Node 0 DMA32: 4*4kB 3*8kB 2*16kB 3*32kB 4*64kB 5*128kB 3*256kB 5*512kB
4*1024kB 5*2048kB 776*4096kB = 3197224kB
Node 0 Normal: 14*4kB 14*8kB 8*16kB 6*32kB 1*64kB 3*128kB 3*256kB
2*512kB 4*1024kB 1*2048kB 28*4096kB = 123560kB
64847 total pagecache pages
0 pages in swap cache
Swap cache stats: add 0, delete 0, find 0/0
Free swap  = 502752kB
Total swap = 502752kB
1048576 pages RAM
52120 pages reserved
71967 pages shared
143004 pages non-shared

 --- [2]

BUG: unable to handle kernel NULL pointer dereference at 00000000000002c8
IP: [<ffffffff8046c84c>] map_single+0x1c/0x280
PGD 10e54e067 PUD 10e595067 PMD 0
Oops: 0000 [1] PREEMPT SMP DEBUG_PAGEALLOC
CPU 0
Modules linked in: kvm_intel kvm microcode uvcvideo compat_ioctl32
videodev v4l1_compat shpchp pci_hotplug
Pid: 5895, comm: skype Not tainted 2.6.27-rc6-235c-debug #1
RIP: 0010:[<ffffffff8046c84c>]  [<ffffffff8046c84c>] map_single+0x1c/0x280
RSP: 0018:ffff88010e78d988  EFLAGS: 00210296
RAX: 0000780000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000005000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88010e78d9e8 R08: 0000000000000000 R09: 0000000000000001
R10: ffff88010e78d698 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000005000 R15: ffff88012f1c9968
FS:  0000000000000000(0000) GS:ffffffff80a6cdc0(0063) knlGS:00000000f6355b90
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000000002c8 CR3: 000000010e57d000 CR4: 00000000000026e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process skype (pid: 5895, threadinfo ffff88010e78c000, task ffff88012b9cc460)
Stack:  0000000200000000 0000000000005000 0000000000000000 0000000000000000
 00000000000017b8 0000000000000000 ffff88010e78d9c8 0000000000000000
 0000000000000002 0000000000000000 0000000000005000 ffff88012f1c9968
Call Trace:
 [<ffffffff8046cbb0>] swiotlb_map_single_attrs+0x60/0xf0
 [<ffffffff8046cc4c>] swiotlb_map_single+0xc/0x10
 [<ffffffff8046cdee>] swiotlb_alloc_coherent+0xfe/0x180
 [<ffffffff80212731>] dma_alloc_coherent+0x281/0x310
 [<ffffffff805621c0>] hcd_buffer_alloc+0x50/0x90
 [<ffffffff805547fd>] usb_buffer_alloc+0x2d/0x40
 [<ffffffffa0056763>] uvc_alloc_urb_buffers+0x53/0xf0 [uvcvideo]
 [<ffffffffa0056958>] uvc_init_video+0x158/0x3e0 [uvcvideo]
 [<ffffffffa0056c17>] uvc_video_enable+0x37/0x80 [uvcvideo]
 [<ffffffffa0055853>] uvc_v4l2_do_ioctl+0x723/0x1260 [uvcvideo]
 [<ffffffff8026dd61>] ? trace_hardirqs_off_caller+0x21/0xc0
 [<ffffffff8026dd61>] ? trace_hardirqs_off_caller+0x21/0xc0
 [<ffffffffa0032c9f>] video_usercopy+0x19f/0x390 [videodev]
 [<ffffffffa0055130>] ? uvc_v4l2_do_ioctl+0x0/0x1260 [uvcvideo]
 [<ffffffff8026d0ce>] ? put_lock_stats+0xe/0x30
 [<ffffffffa0054dad>] uvc_v4l2_ioctl+0x4d/0x80 [uvcvideo]
 [<ffffffffa0045083>] native_ioctl+0x83/0x90 [compat_ioctl32]
 [<ffffffffa004534e>] v4l_compat_ioctl32+0x2be/0x1da4 [compat_ioctl32]
 [<ffffffff806aad21>] ? do_page_fault+0x3d1/0xae0
 [<ffffffff80270ccd>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff80270c59>] ? trace_hardirqs_on_caller+0x149/0x1b0
 [<ffffffff80270ccd>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff80329afa>] compat_sys_ioctl+0x8a/0x3c0
 [<ffffffff806a700d>] ? trace_hardirqs_off_thunk+0x3a/0x3c
 [<ffffffff8022f816>] sysenter_dispatch+0x7/0x2c
 [<ffffffff806a6fce>] ? trace_hardirqs_on_thunk+0x3a/0x3f

Code: 45 31 c0 48 89 e5 e8 a4 ff ff ff c9 c3 66 90 55 48 89 e5 41 57
41 56 41 55 41 54 53 48 83 ec 38 48 89 75 b0 48 89 55 a8 89 4d a4 <48>
8b 87 c8 02 00 00 48 85 c0 0f 84 1c 02 00 00 48 8b 58 08 48
RIP  [<ffffffff8046c84c>] map_single+0x1c/0x280
 RSP <ffff88010e78d988>
CR2: 00000000000002c8
---[ end trace 5d15baeeb7025a0e ]---

 --- [3]

ffffffff8046c830 <map_single>:
map_single():
/store/kernel/linux/lib/swiotlb.c:291
ffffffff8046c830:       55                      push   %rbp
ffffffff8046c831:       48 89 e5                mov    %rsp,%rbp
ffffffff8046c834:       41 57                   push   %r15
ffffffff8046c836:       41 56                   push   %r14
ffffffff8046c838:       41 55                   push   %r13
ffffffff8046c83a:       41 54                   push   %r12
ffffffff8046c83c:       53                      push   %rbx
ffffffff8046c83d:       48 83 ec 38             sub    $0x38,%rsp
ffffffff8046c841:       48 89 75 b0             mov    %rsi,-0x50(%rbp)
ffffffff8046c845:       48 89 55 a8             mov    %rdx,-0x58(%rbp)
ffffffff8046c849:       89 4d a4                mov    %ecx,-0x5c(%rbp)
dma_get_seg_boundary():
/store/kernel/linux/include/linux/dma-mapping.h:80
ffffffff8046c84c:       48 8b 87 c8 02 00 00    mov    0x2c8(%rdi),%rax <----

 --- [4]
Signed-off-by: NDaniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

It was introduced by "vsprintf: add support for '%pS' and '%pF' pointer
formats" in commit 0fe1ef24.  However,
the current way its coded doesn't work on parisc64.  For two reasons: 1)
parisc isn't in the #ifdef and 2) parisc has a different format for
function descriptors

Make dereference_function_descriptor() more accommodating by allowing
architecture overrides.  I put the three overrides (for parisc64, ppc64
and ia64) in arch/kernel/module.c because that's where the kernel
internal linker which knows how to deal with function descriptors sits.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NTony Luck <tony.luck@intel.com>
Acked-by: NKyle McMartin <kyle@mcmartin.ca>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This adds is_swiotlb_buffer() helper function to see whether a buffer
belongs to the swiotlb buffer or not.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We don't need any check in swiotlb_unmap_single here. unmap_single is
appropriate.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>