In file included from arch/x86/kernel/asm-offsets_32.c:9,
from arch/x86/kernel/asm-offsets.c:3:
include/linux/sched.h: In function ‘thread_group_cputime_clone_thread’:
include/linux/sched.h:2272: warning: no return statement in function returning non-void
include/linux/sched.h: In function ‘thread_group_cputime_account_user’:
include/linux/sched.h:2284: error: invalid type argument of ‘->’ (have ‘struct task_cputime’)
include/linux/sched.h:2284: error: invalid type argument of ‘->’ (have ‘struct task_cputime’)
include/linux/sched.h: In function ‘thread_group_cputime_account_system’:
include/linux/sched.h:2291: error: invalid type argument of ‘->’ (have ‘struct task_cputime’)
include/linux/sched.h:2291: error: invalid type argument of ‘->’ (have ‘struct task_cputime’)
include/linux/sched.h: In function ‘thread_group_cputime_account_exec_runtime’:
include/linux/sched.h:2298: error: invalid type argument of ‘->’ (have ‘struct task_cputime’)
distcc[14501] ERROR: compile arch/x86/kernel/asm-offsets.c on a/30 failed
make[1]: *** [arch/x86/kernel/asm-offsets.s] Error 1
kernel/fork.c:843: error: ‘struct signal_struct’ has no member named ‘sum_sched_runtime’
kernel/irq/handle.c:117: warning: ‘sparse_irq_lock’ defined but not used
Frank Mayhar [Fri, 12 Sep 2008 16:54:39 +0000 (09:54 -0700)]
timers: fix itimer/many thread hang
Overview
This patch reworks the handling of POSIX CPU timers, including the
ITIMER_PROF, ITIMER_VIRT timers and rlimit handling. It was put together
with the help of Roland McGrath, the owner and original writer of this code.
The problem we ran into, and the reason for this rework, has to do with using
a profiling timer in a process with a large number of threads. It appears
that the performance of the old implementation of run_posix_cpu_timers() was
at least O(n*3) (where "n" is the number of threads in a process) or worse.
Everything is fine with an increasing number of threads until the time taken
for that routine to run becomes the same as or greater than the tick time, at
which point things degrade rather quickly.
This patch fixes bug 9906, "Weird hang with NPTL and SIGPROF."
Code Changes
This rework corrects the implementation of run_posix_cpu_timers() to make it
run in constant time for a particular machine. (Performance may vary between
one machine and another depending upon whether the kernel is built as single-
or multiprocessor and, in the latter case, depending upon the number of
running processors.) To do this, at each tick we now update fields in
signal_struct as well as task_struct. The run_posix_cpu_timers() function
uses those fields to make its decisions.
We define a new structure, "task_cputime," to contain user, system and
scheduler times and use these in appropriate places:
struct task_cputime {
cputime_t utime;
cputime_t stime;
unsigned long long sum_exec_runtime;
};
This is included in the structure "thread_group_cputime," which is a new
substructure of signal_struct and which varies for uniprocessor versus
multiprocessor kernels. For uniprocessor kernels, it uses "task_cputime" as
a simple substructure, while for multiprocessor kernels it is a pointer:
We also add a new task_cputime substructure directly to signal_struct, to
cache the earliest expiration of process-wide timers, and task_cputime also
replaces the it_*_expires fields of task_struct (used for earliest expiration
of thread timers). The "thread_group_cputime" structure contains process-wide
timers that are updated via account_user_time() and friends. In the non-SMP
case the structure is a simple aggregator; unfortunately in the SMP case that
simplicity was not achievable due to cache-line contention between CPUs (in
one measured case performance was actually _worse_ on a 16-cpu system than
the same test on a 4-cpu system, due to this contention). For SMP, the
thread_group_cputime counters are maintained as a per-cpu structure allocated
using alloc_percpu(). The timer functions update only the timer field in
the structure corresponding to the running CPU, obtained using per_cpu_ptr().
We define a set of inline functions in sched.h that we use to maintain the
thread_group_cputime structure and hide the differences between UP and SMP
implementations from the rest of the kernel. The thread_group_cputime_init()
function initializes the thread_group_cputime structure for the given task.
The thread_group_cputime_alloc() is a no-op for UP; for SMP it calls the
out-of-line function thread_group_cputime_alloc_smp() to allocate and fill
in the per-cpu structures and fields. The thread_group_cputime_free()
function, also a no-op for UP, in SMP frees the per-cpu structures. The
thread_group_cputime_clone_thread() function (also a UP no-op) for SMP calls
thread_group_cputime_alloc() if the per-cpu structures haven't yet been
allocated. The thread_group_cputime() function fills the task_cputime
structure it is passed with the contents of the thread_group_cputime fields;
in UP it's that simple but in SMP it must also safely check that tsk->signal
is non-NULL (if it is it just uses the appropriate fields of task_struct) and,
if so, sums the per-cpu values for each online CPU. Finally, the three
functions account_group_user_time(), account_group_system_time() and
account_group_exec_runtime() are used by timer functions to update the
respective fields of the thread_group_cputime structure.
Non-SMP operation is trivial and will not be mentioned further.
The per-cpu structure is always allocated when a task creates its first new
thread, via a call to thread_group_cputime_clone_thread() from copy_signal().
It is freed at process exit via a call to thread_group_cputime_free() from
cleanup_signal().
All functions that formerly summed utime/stime/sum_sched_runtime values from
from all threads in the thread group now use thread_group_cputime() to
snapshot the values in the thread_group_cputime structure or the values in
the task structure itself if the per-cpu structure hasn't been allocated.
Finally, the code in kernel/posix-cpu-timers.c has changed quite a bit.
The run_posix_cpu_timers() function has been split into a fast path and a
slow path; the former safely checks whether there are any expired thread
timers and, if not, just returns, while the slow path does the heavy lifting.
With the dedicated thread group fields, timers are no longer "rebalanced" and
the process_timer_rebalance() function and related code has gone away. All
summing loops are gone and all code that used them now uses the
thread_group_cputime() inline. When process-wide timers are set, the new
task_cputime structure in signal_struct is used to cache the earliest
expiration; this is checked in the fast path.
Performance
The fix appears not to add significant overhead to existing operations. It
generally performs the same as the current code except in two cases, one in
which it performs slightly worse (Case 5 below) and one in which it performs
very significantly better (Case 2 below). Overall it's a wash except in those
two cases.
I've since done somewhat more involved testing on a dual-core Opteron system.
Case 1: With no itimer running, for a test with 100,000 threads, the fixed
kernel took 1428.5 seconds, 513 seconds more than the unfixed system,
all of which was spent in the system. There were twice as many
voluntary context switches with the fix as without it.
Case 2: With an itimer running at .01 second ticks and 4000 threads (the most
an unmodified kernel can handle), the fixed kernel ran the test in
eight percent of the time (5.8 seconds as opposed to 70 seconds) and
had better tick accuracy (.012 seconds per tick as opposed to .023
seconds per tick).
Case 3: A 4000-thread test with an initial timer tick of .01 second and an
interval of 10,000 seconds (i.e. a timer that ticks only once) had
very nearly the same performance in both cases: 6.3 seconds elapsed
for the fixed kernel versus 5.5 seconds for the unfixed kernel.
With fewer threads (eight in these tests), the Case 1 test ran in essentially
the same time on both the modified and unmodified kernels (5.2 seconds versus
5.8 seconds). The Case 2 test ran in about the same time as well, 5.9 seconds
versus 5.4 seconds but again with much better tick accuracy, .013 seconds per
tick versus .025 seconds per tick for the unmodified kernel.
Since the fix affected the rlimit code, I also tested soft and hard CPU limits.
Case 4: With a hard CPU limit of 20 seconds and eight threads (and an itimer
running), the modified kernel was very slightly favored in that while
it killed the process in 19.997 seconds of CPU time (5.002 seconds of
wall time), only .003 seconds of that was system time, the rest was
user time. The unmodified kernel killed the process in 20.001 seconds
of CPU (5.014 seconds of wall time) of which .016 seconds was system
time. Really, though, the results were too close to call. The results
were essentially the same with no itimer running.
Case 5: With a soft limit of 20 seconds and a hard limit of 2000 seconds
(where the hard limit would never be reached) and an itimer running,
the modified kernel exhibited worse tick accuracy than the unmodified
kernel: .050 seconds/tick versus .028 seconds/tick. Otherwise,
performance was almost indistinguishable. With no itimer running this
test exhibited virtually identical behavior and times in both cases.
In times past I did some limited performance testing. those results are below.
On a four-cpu Opteron system without this fix, a sixteen-thread test executed
in 3569.991 seconds, of which user was 3568.435s and system was 1.556s. On
the same system with the fix, user and elapsed time were about the same, but
system time dropped to 0.007 seconds. Performance with eight, four and one
thread were comparable. Interestingly, the timer ticks with the fix seemed
more accurate: The sixteen-thread test with the fix received 149543 ticks
for 0.024 seconds per tick, while the same test without the fix received 58720
for 0.061 seconds per tick. Both cases were configured for an interval of
0.01 seconds. Again, the other tests were comparable. Each thread in this
test computed the primes up to 25,000,000.
I also did a test with a large number of threads, 100,000 threads, which is
impossible without the fix. In this case each thread computed the primes only
up to 10,000 (to make the runtime manageable). System time dominated, at
1546.968 seconds out of a total 2176.906 seconds (giving a user time of
629.938s). It received 147651 ticks for 0.015 seconds per tick, still quite
accurate. There is obviously no comparable test without the fix.
Signed-off-by: Frank Mayhar <fmayhar@google.com> Cc: Roland McGrath <roland@redhat.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] Fix PCI_DMA_BUS_IS_PHYS for ARM
[ARM] 5247/1: tosa: SW_EAR_IN support
[ARM] 5246/1: tosa: add proper clock alias for tc6393xb clock
[ARM] 5245/1: Fix warning about unused return value in drivers/pcmcia
[ARM] OMAP: Fix MMC device data
imx serial: fix rts handling for non imx1 based hardware
imx serial: set RXD mux bit on i.MX27 and i.MX31
i.MX serial: fix init failure
pcm037: add rts/cts support for serial port
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
niu: panic on reset
netlink: fix overrun in attribute iteration
[Bluetooth] Fix regression from using default link policy
ath9k: Assign seq# when mac80211 requests this
Alex Dubov [Sat, 13 Sep 2008 09:33:26 +0000 (02:33 -0700)]
memstick: fix MSProHG 8-bit interface mode support
- 8-bit interface mode never worked properly. The only adapter I have
which supports the 8b mode (the Jmicron) had some problems with its
clock wiring and they discovered it only now. We also discovered that
ProHG media is more sensitive to the ordering of initialization
commands.
- Make the driver fall back to highest supported mode instead of always
falling back to serial. The driver will attempt the switch to 8b mode
for any new MSPro card, but not all of them support it. Previously,
these new cards ended up in serial mode, which is not the best idea
(they work fine with 4b, after all).
- Edit some macros for better conformance to Sony documentation
Signed-off-by: Alex Dubov <oakad@yahoo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Sat, 13 Sep 2008 09:33:25 +0000 (02:33 -0700)]
rescan_partitions(): make device capacity errors non-fatal
Herton Krzesinski reports that the error-checking changes in 04ebd4aee52b06a2c38127d9208546e5b96f3a19 ("block/ioctl.c and
fs/partition/check.c: check value returned by add_partition") cause his
buggy USB camera to no longer mount. "The camera is an Olympus X-840.
The original issue comes from the camera itself: its format program
creates a partition with an off by one error".
Buggy devices happen. It is better for the kernel to warn and to proceed
with the mount.
Reported-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br> Cc: Abdel Benamrouche <draconux@gmail.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ben Dooks [Sat, 13 Sep 2008 09:33:24 +0000 (02:33 -0700)]
spi_s3c24xx: fix section warning
Fix the section mismatch warning generated by the incorrect naming of
s3c24xx_spidrv which should be s3c24xx_spi_driver:
WARNING: drivers/spi/spi_s3c24xx.o(.data+0x4):
Section mismatch in reference from the variable s3c24xx_spidrv
to the (unknown reference) .exit.text:(unknown)
Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
atmel_lcdfb: disable LCD and DMA engines when suspending
When suspending the system with atmel_lcdfb enabled, I sometimes see
this:
atmel_lcdfb atmel_lcdfb.0: FIFO underflow 0x10
Which can be explained by the fact that we're not stopping the LCD
controller and its DMA engine when suspending, we're just gating the
clocks to them.
There's another potential issue which may be harder to trigger but
much more nasty: If we gate the clocks at _just_ the right moment,
e.g. when the DMA engine is doing a bus transaction, we may cause the
DMA engine to violate the system bus protocol and cause a lockup.
Avoid these issues by shutting down the LCD controller before entering
suspend (and restarting it when resuming). This prevents the underrun
from happening in the first place, and prevents whatever nastiness is
happening when the bus clock stops in the middle of a DMA transfer.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Robin Holt [Sat, 13 Sep 2008 09:33:22 +0000 (02:33 -0700)]
ia64: fix panic during `modprobe -r xpc'
If you are on ia64 and you modprobe xpc then modprobe -r xpc, you
immediately get a panic. xpc depends on xp which depends on gru for a
symbol. That symbol is only used when we are running on UV hardware.
Currently, the GRU driver detects we are not on UV hardware and does no
initializing. It does not do the same check when unloading. As a result,
the gru driver attempts to tear down stuff that was not setup.
This is a simple two-line workaround to get us through this release. Once
2.6.28 is opened, we need to rework the symbols that xp is depending on
from gru so the gru driver can properly fail to load when hardware is not
available.
Signed-off-by: Robin Holt <holt@sgi.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: mark the correct zone as full when scanning zonelists
The iterator for_each_zone_zonelist() uses a struct zoneref *z cursor when
scanning zonelists to keep track of where in the zonelist it is. The
zoneref that is returned corresponds to the the next zone that is to be
scanned, not the current one. It was intended to be treated as an opaque
list.
When the page allocator is scanning a zonelist, it marks elements in the
zonelist corresponding to zones that are temporarily full. As the
zonelist is being updated, it uses the cursor here;
if (NUMA_BUILD)
zlc_mark_zone_full(zonelist, z);
This is intended to prevent rescanning in the near future but the zoneref
cursor does not correspond to the zone that has been found to be full.
This is an easy misunderstanding to make so this patch corrects the
problem by changing zoneref cursor to be the current zone being scanned
instead of the next one.
Ned Forrester [Sat, 13 Sep 2008 09:33:18 +0000 (02:33 -0700)]
pxa2xx_spi: dma bugfixes
Fixes two DMA bugs in the pxa2xx_spi driver. The first bug is in all
versions of this driver; the second was introduced in the 2.6.20 kernel,
and prevents using the driver with chips like m25p16 flash (which can
issue large DMA reads).
1. Zero length transfers are permitted for use to insert timing,
but pxa2xx_spi.c will fail if this is requested in DMA mode.
Fixed by using programmed I/O (PIO) mode for such transfers.
2. Transfers larger than 8191 are not permitted in DMA mode. A
test for length rejects all large transfers regardless of DMA
or PIO mode. Worked around by rejecting only large transfers
with DMA mapped buffers, and forcing all other transfers
larger than 8191 to use PIO mode. A rate limited warning is
issued for DMA transfers forced to PIO mode.
This patch should apply to all kernels back to and including 2.6.20;
it was test patched against 2.6.20. An additional patch would be
required for older kernels, but those versions are very buggy anyway.
Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ned Forrester [Sat, 13 Sep 2008 09:33:17 +0000 (02:33 -0700)]
pxa2xx_spi: chipselect bugfixes
Fixes several chipselect bugs in the pxa2xx_spi driver. These bugs are in
all versions of this driver and prevent using it with chips like m25p16
flash.
1. The spi_transfer.cs_change flag is handled too early:
before spi_transfer.delay_usecs applies, thus making the
delay ineffective at holding chip select.
2. spi_transfer.delay_usecs is ignored on the last transfer
of a message (likewise not holding chipselect long enough).
3. If spi_transfer.cs_change is set on the last transfer, the
chip select is always disabled, instead of the intended
meaning: optionally holding chip select enabled for the
next message.
Those first three bugs were fixed with a relocation of delays
and chip select de-assertions.
4. If a message has the cs_change flag set on the last transfer,
and had the chip select stayed enabled as requested (see 3,
above), it would not have been disabled if the next message is
for a different chip. Fixed by dropping chip select regardless
of cs_change at end of a message, if there is no next message
or if the next message is for a different chip.
This patch should apply to all kernels back to and including 2.6.20;
it was test patched against 2.6.20. An additional patch would be
required for older kernels, but those versions are very buggy anyway.
Signed-off-by: Ned Forrester <nforrester@whoi.edu> Cc: Vernon Sauder <vernoninhand@gmail.com> Cc: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Peter Korsgaard [Sat, 13 Sep 2008 09:33:14 +0000 (02:33 -0700)]
spi_mpc83xx: fix clockrate calculation for low speed
Commit a61f5345 (spi_mpc83xx clockrate fixes) broke clockrate calculation
for low speeds. SPMODE_DIV16 should be set if the divider is higher than
64, not only if the divider gets clipped to 1024.
Furthermore, the clipping check was off by a factor 16 as well.
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A "Quicklists: 0 kB" line has just started appearing in
/proc/meminfo, but most architectures (including x86) don't have
them configured, so #ifdef it, like the highmem lines.
And those architectures which do have quicklists configured are
using them for page tables: so let's place it next to PageTables.
Signed-off-by: Hugh Dickins <hugh@veritas.com> Acked-by: Christoph Lameter <cl@linux-foundation.org> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric Sesterhenn [Sat, 13 Sep 2008 09:33:12 +0000 (02:33 -0700)]
bfs: fix Lockdep warning
This fixes:
=============================================
[ INFO: possible recursive locking detected ] 2.6.27-rc5-00283-g70bb089 #68
---------------------------------------------
touch/6855 is trying to acquire lock:
(&info->bfs_lock){--..}, at: [<c02262f5>] bfs_delete_inode+0x9e/0x18c
but task is already holding lock:
(&info->bfs_lock){--..}, at: [<c0226c00>] bfs_create+0x45/0x187
other info that might help us debug this:
2 locks held by touch/6855:
#0: (&type->i_mutex_dir_key#5){--..}, at: [<c018ad13>] do_filp_open+0x10b/0x62f
#1: (&info->bfs_lock){--..}, at: [<c0226c00>] bfs_create+0x45/0x187
Li Zefan [Sat, 13 Sep 2008 09:33:09 +0000 (02:33 -0700)]
cpuset: hotplug documentation fix
If all the cpus in a cpuset are offlined, the tasks in it will be moved to
the nearest ancestor with non-empty cpus.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Paul Jackson <pj@sgi.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cpusets: restructure the function update_cpumask() and update_nodemask()
It might happen that 'echo 0 > /cpuset/sub/cpus' returned failure but 'cpus'
has been changed, because cpus was changed before calling heap_init() which
may return -ENOMEM.
This patch restores the orginal behavior.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Paul Menage <menage@google.com> Cc: Paul Jackson <pj@sgi.com> Cc: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
proc: more debugging for "already registered" case
Print parent directory name as well.
The aim is to catch non-creation of parent directory when proc_mkdir will
return NULL and all subsequent registrations go directly in /proc instead
of intended directory.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Fixed insane printk string while at it. - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I recently bought 3 HGST P7K500-series 500GB SATA drives and
had trouble accessing the block right on the LBA28-LBA48 border.
Here's how it fails (same for all 3 drives):
# dd if=/dev/sdc bs=512 count=1 skip=268435455 > /dev/null
dd: reading `/dev/sdc': Input/output error
0+0 records in
0+0 records out
0 bytes (0 B) copied, 0.288033 seconds, 0.0 kB/s
# dmesg
ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x25
ata1.00: cmd c8/00:08:f8:ff:ff/00:00:00:00:00/ef tag 0 dma 4096 in
res 51/04:08:f8:ff:ff/00:00:00:00:00/ef Emask 0x1 (device error)
ata1.00: status: { DRDY ERR }
ata1.00: error: { ABRT }
ata1.00: configured for UDMA/33
ata1: EH complete
...
After some investigations, it turned out this seems to be caused
by misinterpretation of the ATA specification on LBA28 access.
Following part is the code in question:
HGST drive (sometimes) fails with LBA28 access of {block = 0xfffffff,
n_block = 1}, and this behavior seems to be comformant. Other drives,
including other HGST drives are not that strict, through.
>From the ATA specification:
(http://www.t13.org/Documents/UploadedDocuments/project/d1410r3b-ATA-ATAPI-6.pdf)
8.15.29 Word (61:60): Total number of user addressable sectors
This field contains a value that is one greater than the total number
of user addressable sectors (see 6.2). The maximum value that shall
be placed in this field is 0FFFFFFFh.
So the driver shouldn't use the value of 0xfffffff for LBA28 request
as this exceeds maximum user addressable sector. The logical maximum
value for LBA28 is 0xffffffe.
The obvious fix is to cut "- 1" part, and the patch attached just do
that. I've been using the patched kernel for about a month now, and
the same fix is also floating on the net for some time. So I believe
this fix works reliably.
Just FYI, many Windows/Intel platform users also seems to be struck
by this, and HGST has issued a note pointing to Intel ICH8/9 driver.
Russell King [Sat, 13 Sep 2008 20:23:06 +0000 (21:23 +0100)]
[ARM] Fix PCI_DMA_BUS_IS_PHYS for ARM
PCI_DMA_BUS_IS_PHYS was defined to be zero, which meant we ignored
the DMA mask for IDE and SCSI transfers. This is wrong - we have
no DMA translation hardware. We want to obey DMA masks so that the
block layer performs bouncing itself.
Reported-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Acked-by: Eric Miao <eric.miao@marvell.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[ARM] 5246/1: tosa: add proper clock alias for tc6393xb clock
Add clock alias for clock that is used by tc6393xb device on tosa.
As that chip plays pretty major part in tosa life and is currently
disabled, this is 2.4.27 material.
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Santwona Behera [Fri, 12 Sep 2008 23:04:26 +0000 (16:04 -0700)]
niu: panic on reset
The reset_task function in the niu driver does not reset the tx and rx
buffers properly. This leads to panic on reset. This patch is a
modified implementation of the previously posted fix.
Signed-off-by: Santwona Behera <santwona.behera@sun.com> Signed-off-by: David S. Miller <davem@davemloft.net>
/**
* nla_ok - check if the netlink attribute fits into the remaining bytes
* @nla: netlink attribute
* @remaining: number of bytes remaining in attribute stream
*/
static inline int nla_ok(const struct nlattr *nla, int remaining)
{
return remaining >= sizeof(*nla) &&
nla->nla_len >= sizeof(*nla) &&
nla->nla_len <= remaining;
}
It turns out that remaining can become negative due to alignment in
nla_next(). But GCC promotes "remaining" to unsigned in the test
against sizeof(*nla) above. Therefore the test succeeds, and the
nla_for_each_attr() may access memory outside the received buffer.
A short example illustrating this point is here:
#include <stdio.h>
main(void)
{
printf("%d\n", -1 >= sizeof(int));
}
...which prints "1".
This patch adds a cast in front of the sizeof so that GCC will make
a signed comparison and fix the illegal memory dereference. With the
patch applied, there is no kmemcheck report.
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
[Bluetooth] Fix regression from using default link policy
To speed up the Simple Pairing connection setup, the support for the
default link policy has been enabled. This is in contrast to settings
the link policy on every connection setup. Using the default link policy
is the preferred way since there is no need to dynamically change it for
every connection.
For backward compatibility reason and to support old userspace the
HCISETLINKPOL ioctl has been switched over to using hci_request() to
issue the HCI command for setting the default link policy instead of
just storing it in the HCI device structure.
However the hci_request() can only be issued when the device is
brought up. If used on a device that is registered, but still down
it will timeout and fail. This is problematic since the command is
put on the TX queue and the Bluetooth core tries to submit it to
hardware that is not ready yet. The timeout for these requests is
10 seconds and this causes a significant regression when setting up
a new device.
The userspace can perfectly handle a failure of the HCISETLINKPOL
ioctl and will re-submit it later, but the 10 seconds delay causes
a problem. So in case hci_request() is called on a device that is
still down, just fail it with ENETDOWN to indicate what happens.
David Howells [Thu, 11 Sep 2008 16:18:56 +0000 (17:18 +0100)]
MN10300: Change the fault handler to check in_atomic() not in_interrupt()
Change the MN10300 fault handler to make it check in_atomic() rather than
in_interrupt() as commit 6edaf68a87d17570790fd55f0c451a29ec1d6703 did for other
architectures:
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Wed Dec 6 20:32:18 2006 -0800
[PATCH] mm: arch do_page_fault() vs in_atomic()
In light of the recent pagefault and filemap_copy_from_user work I've
gone through all the arch pagefault handlers to make sure the
inc_preempt_count() 'feature' works as expected.
Several sections of code (including the new filemap_copy_from_user)
rely on the fact that faults do not take locks under increased preempt
count.
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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.
Merge branch 'kvm-updates/2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: VMX: Always return old for clear_flush_young() when using EPT
KVM: SVM: fix guest global tlb flushes with NPT
KVM: SVM: fix random segfaults with NPT enabled
Jouni Malinen [Mon, 11 Aug 2008 11:01:50 +0000 (14:01 +0300)]
ath9k: Assign seq# when mac80211 requests this
Use TX control flag IEEE80211_TX_CTL_ASSIGN_SEQ as a request to update
the seq# for the frames. This will likely require some further cleanup
to get seq# correctly for Beacons vs. other frames and also potentially
for multiple BSSes. Anyway, this is better than ending up sending out
most frames with seq# 0.
(This is a backport of patch w/ same title already in net-next-2.6.
It is verified to fix http://bugzilla.kernel.org/show_bug.cgi?id=11394
and it should be acceptable for -rc due to the driver being new
in 2.6.27.)
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
block: disable sysfs parts of the disk command filter
We still have life time issues with the sysfs command filter kobject,
so disable it for 2.6.27 release. We can revisit this and make it work
properly for 2.6.28, for 2.6.27 release it's too risky.
Russell King [Tue, 9 Sep 2008 09:16:22 +0000 (10:16 +0100)]
[ARM] OMAP: Fix MMC device data
OMAPs MMC device data was passing the wrong structure via the platform
device. Moreover, a missing function means that both sx1_defconfig
and omap_h2_1610_defconfig builds failed with
undefined reference to `omap_set_mmc_info'
errors. Fix this by updating the MMC support from the omapzoom tree.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Accesses to CR4 are intercepted even with Nested Paging enabled. But the code
does not check if the guest wants to do a global TLB flush. So this flush gets
lost. This patch adds the check and the flush to svm_set_cr4.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Joerg Roedel [Wed, 27 Aug 2008 12:18:43 +0000 (14:18 +0200)]
KVM: SVM: fix random segfaults with NPT enabled
This patch introduces a guest TLB flush on every NPF exit in KVM. This fixes
random segfaults and #UD exceptions in the guest seen under some workloads
(e.g. long running compile workloads or tbench). A kernbench run with and
without that fix showed that it has a slowdown lower than 0.5%
Cc: stable@kernel.org Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@qumranet.com>
commit 0d3244d6439c8c31d2a29efd587c7aca9042c8aa ("V4L/DVB (8342):
sh_mobile_ceu_camera: Add SuperH Mobile CEU driver V3") introduced
VIDEO_SH_MOBILE_CEU, which selects VIDEOBUF_DMA_CONTIG. This circumvents the
dependency on HAS_DMA of VIDEOBUF_DMA_CONTIG.
Add a dependency on HAS_DMA to VIDEO_SH_MOBILE_CEU to fix this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
swiotlb: fix back-off path when memory allocation fails
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).
ide: Fix pointer arithmetic in hpt3xx driver code (3rd try)
git commit 74811f355f4f69a187fa74892dcf2a684b84ce99 causes crash at
module load (or boot) time on my machine with a hpt374 controller.
The reason for this is that for initializing second controller which sets
(hwif->dev == host->dev[1]) to true (1), adds 1 to a void ptr, which
advances it by one byte instead of advancing it by sizeof(hpt_info) bytes.
Because of this, all initialization functions get corrupted data in info
variable which causes a crash at boot time.
This patch fixes that and makes my machine boot again.
The card itself is a HPT374 raid conroller: Here is the lspci -v output:
03:06.0 RAID bus controller: HighPoint Technologies, Inc. HPT374 (rev
07)
Subsystem: HighPoint Technologies, Inc. Unknown device 0001
Flags: bus master, 66MHz, medium devsel, latency 120, IRQ 28
I/O ports at 8000 [size=8]
I/O ports at 7800 [size=4]
I/O ports at 7400 [size=8]
I/O ports at 7000 [size=4]
I/O ports at 6800 [size=256]
Expansion ROM at fe8e0000 [disabled] [size=128K]
Capabilities: [60] Power Management version 2
03:06.1 RAID bus controller: HighPoint Technologies, Inc. HPT374 (rev
07)
Subsystem: HighPoint Technologies, Inc. Unknown device 0001
Flags: bus master, 66MHz, medium devsel, latency 120, IRQ 28
I/O ports at 9800 [size=8]
I/O ports at 9400 [size=4]
I/O ports at 9000 [size=8]
I/O ports at 8800 [size=4]
I/O ports at 8400 [size=256]
Capabilities: [60] Power Management version 2
Signed-off-by: Masoud Sharbiani <masouds@google.com> Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com> Cc: Andrew Morton <akpm@linux-foundation.org>
[bart: use dev_get_drvdata() per Sergei's suggestion] Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Paul E. McKenney [Sun, 31 Aug 2008 18:06:30 +0000 (11:06 -0700)]
[IA64] prevent ia64 from invoking irq handlers on offline CPUs
Make ia64 refrain from clearing a given to-be-offlined CPU's bit in the
cpu_online_mask until it has processed pending irqs. This change
prevents other CPUs from being blindsided by an apparently offline CPU
nevertheless changing globally visible state. Also remove the existing
redundant cpu_clear(cpu, cpu_online_map).
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Robin Holt [Tue, 9 Sep 2008 15:34:44 +0000 (10:34 -0500)]
[IA64] fix up bte.h
bte.h expects a #define of L1_CACHE_MASK which is currently only
in bte.c. This small patch gets bte.h to include cleanly and makes
BTE_UNALIGNED_COPY not report errors.
Signed-off-by: Robin Holt <holt@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
James Bottomley [Tue, 9 Sep 2008 22:56:47 +0000 (17:56 -0500)]
[IA64] fix compile failure with non modular builds
Broke the non modular builds by moving an essential function into
modules.c. Fix this by moving it out again and into asm/sections.h as
an inline. To do this, the definitions of struct fdesc and struct
got_val have been lifted out of modules.c and put in asm/elf.h where
they belong.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Tao Ma [Tue, 2 Sep 2008 17:57:14 +0000 (01:57 +0800)]
ocfs2: Fix a bug in direct IO read.
ocfs2 will become read-only if we try to read the bytes which pass
the end of i_size. This can be easily reproduced by following steps:
1. mkfs a ocfs2 volume with bs=4k cs=4k and nosparse.
2. create a small file(say less than 100 bytes) and we will create the file
which is allocated 1 cluster.
3. read 8196 bytes from the kernel using O_DIRECT which exceeds the limit.
4. The ocfs2 volume becomes read-only and dmesg shows:
OCFS2: ERROR (device sda13): ocfs2_direct_IO_get_blocks:
Inode 66010 has a hole at block 1
File system is now read-only due to the potential of on-disk corruption.
Please run fsck.ocfs2 once the file system is unmounted.
So suppress the ERROR message.
Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
ipv6: Fix OOPS in ip6_dst_lookup_tail().
ipsec: Restore larval states and socket policies in dump
[Bluetooth] Reject L2CAP connections on an insecure ACL link
[Bluetooth] Enforce correct authentication requirements
[Bluetooth] Fix reference counting during ACL config stage
Neil Horman [Tue, 9 Sep 2008 20:51:35 +0000 (13:51 -0700)]
ipv6: Fix OOPS in ip6_dst_lookup_tail().
This fixes kernel bugzilla 11469: "TUN with 1024 neighbours:
ip6_dst_lookup_tail NULL crash"
dst->neighbour is not necessarily hooked up at this point
in the processing path, so blindly dereferencing it is
the wrong thing to do. This NULL check exists in other
similar paths and this case was just an oversight.
Also fix the completely wrong and confusing indentation
here while we're at it.
Based upon a patch by Evgeniy Polyakov.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
clockevents: remove WARN_ON which was used to gather information
Thomas Gleixner [Tue, 9 Sep 2008 19:38:57 +0000 (21:38 +0200)]
clockevents: remove WARN_ON which was used to gather information
The issue of the endless reprogramming loop due to a too small
min_delta_ns was fixed with the previous updates of the clock events
code, but we had no information about the spread of this problem. I
added a WARN_ON to get automated information via kerneloops.org and to
get some direct reports, which allowed me to analyse the affected
machines.
The WARN_ON has served its purpose and would be annoying for a release
kernel. Remove it and just keep the information about the increase of
the min_delta_ns value.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This is happening because of an improper usage of strcmp() in the
e820 parsing code. The strcmp() always returns !0 and never resets the
value for e820.nr_map and returns an incorrect user-defined map.
Merge branch 'linux-next' of git://git.infradead.org/~dedekind/ubifs-2.6
* 'linux-next' of git://git.infradead.org/~dedekind/ubifs-2.6:
UBIFS: make minimum fanout 3
UBIFS: fix division by zero
UBIFS: amend f_fsid
UBIFS: fill f_fsid
UBIFS: improve statfs reporting even more
UBIFS: introduce LEB overhead
UBIFS: add forgotten gc_idx_lebs component
UBIFS: fix assertion
UBIFS: improve statfs reporting
UBIFS: remove incorrect index space check
UBIFS: push empty flash hack down
UBIFS: do not update min_idx_lebs in stafs
UBIFS: allow for racing between GC and TNC
UBIFS: always read hashed-key nodes under TNC mutex
UBIFS: fix zero-length truncations
James Bottomley [Thu, 4 Sep 2008 01:43:36 +0000 (20:43 -0500)]
lib: Correct printk %pF to work on all architectures
It was introduced by "vsprintf: add support for '%pS' and '%pF' pointer
formats" in commit 0fe1ef24f7bd0020f29ffe287dfdb9ead33ca0b2. 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: James Bottomley <James.Bottomley@HansenPartnership.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Tony Luck <tony.luck@intel.com> Acked-by: Kyle McMartin <kyle@mcmartin.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chris Snook [Tue, 9 Sep 2008 07:26:57 +0000 (03:26 -0400)]
MAINTAINERS: add Atheros maintainer for atlx
Jie Yang at Atheros is getting more directly involved with upstream work
on the atl* drivers. This patch changes the ATL1 entry to ATLX (atl2
support posted to netdev today) and adds him as a maintainer.
update Documentation/filesystems/Locking for 2.6.27 changes
In the 2.6.27 circle ->fasync lost the BKL, and the last remaining
->open variant that takes the BKL is also gone. ->get_sb and ->kill_sb
didn't have BKL forever, so updated the entries while we're at that.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alex Chiang [Fri, 5 Sep 2008 21:05:03 +0000 (14:05 -0700)]
PCI Hotplug: fakephp: fix deadlock... again
Commit fe99740cac117f208707488c03f3789cf4904957 (construct one
fakephp slot per PCI slot) introduced a regression, causing a
deadlock when removing a PCI device.
We also never actually removed the device from the PCI core.
So we:
- remove the device from the PCI core
- do not directly call remove_slot() to prevent deadlock
Yu Zhao reported and diagnosed this defect.
Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Yu Zhao <yu.zhao@intel.com> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Again, the cleaned up code introduced some resource warnings:
drivers/pci/setup-bus.c: In function 'pci_bus_dump_res':
drivers/pci/setup-bus.c:542: warning: format '%llx' expects type 'long long unsigned int', but argument 5 has type 'resource_size_t'
drivers/pci/setup-bus.c:542: warning: format '%llx' expects type 'long long unsigned int', but argument 6 has type 'resource_size_t'
Fix those up too.
Signed-off-by: Johann Felix Soden <johfel@users.sourceforge.net> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The cleaned up resource code in probe.c introduced some warnings:
drivers/pci/probe.c: In function 'pci_read_bridge_bases':
drivers/pci/probe.c:386: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'resource_size_t'
drivers/pci/probe.c:386: warning: format '%llx' expects type 'long long unsigned int', but argument 4 has type 'resource_size_t'
drivers/pci/probe.c:398: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'resource_size_t'
drivers/pci/probe.c:398: warning: format '%llx' expects type 'long long unsigned int', but argument 4 has type 'resource_size_t'
drivers/pci/probe.c:434: warning: format '%llx' expects type 'long long unsigned int', but argument 4 has type 'resource_size_t'
drivers/pci/probe.c:434: warning: format '%llx' expects type 'long long unsigned int', but argument 5 has type 'resource_size_t'
So fix them up.
Signed-off-by: Johann Felix Soden <johfel@users.sourceforge.net> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Herbert Xu [Tue, 9 Sep 2008 12:23:37 +0000 (05:23 -0700)]
ipsec: Restore larval states and socket policies in dump
The commit commit 4c563f7669c10a12354b72b518c2287ffc6ebfb3 ("[XFRM]:
Speed up xfrm_policy and xfrm_state walking") inadvertently removed
larval states and socket policies from netlink dumps. This patch
restores them.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
[S390] cio: allow offline processing for disconnected devices
When disconnected ccw devices are removed, the device has to be set
offline, otherwise there will be side effects including a reference
count imbalance. This patch modifies ccw_device_offline to work for
devices in disconnecte/not operational state. ccw_device_offline is
called by cio for devices which are online during device removal.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
ssch() has two classes of return codes:
- condition codes (0-3) which need to be translated to Linux
error codes
- Linux error codes (-EIO on exceptions) which should be passed
to the caller (instead of erronously being handled like
condition code 3)
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Jarod Wilson [Tue, 9 Sep 2008 10:38:56 +0000 (12:38 +0200)]
[S390] CVE-2008-1514: prevent ptrace padding area read/write in 31-bit mode
When running a 31-bit ptrace, on either an s390 or s390x kernel,
reads and writes into a padding area in struct user_regs_struct32
will result in a kernel panic.
This is also known as CVE-2008-1514.
Test case available here:
http://sources.redhat.com/cgi-bin/cvsweb.cgi/~checkout~/tests/ptrace-tests/tests/user-area-padding.c?cvsroot=systemtap
Steps to reproduce:
1) wget the above
2) gcc -o user-area-padding-31bit user-area-padding.c -Wall -ggdb2 -D_GNU_SOURCE -m31
3) ./user-area-padding-31bit
<panic>
Test status
-----------
Without patch, both s390 and s390x kernels panic. With patch, the test case,
as well as the gdb testsuite, pass without incident, padding area reads
returning zero, writes ignored.
Nb: original version returned -EINVAL on write attempts, which broke the
gdb test and made the test case slightly unhappy, Jan Kratochvil suggested
the change to return 0 on write attempts.
Signed-off-by: Jarod Wilson <jarod@redhat.com> Tested-by: Jan Kratochvil <jan.kratochvil@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[Bluetooth] Reject L2CAP connections on an insecure ACL link
The Security Mode 4 of the Bluetooth 2.1 specification has strict
authentication and encryption requirements. It is the initiators job
to create a secure ACL link. However in case of malicious devices, the
acceptor has to make sure that the ACL is encrypted before allowing
any kind of L2CAP connection. The only exception here is the PSM 1 for
the service discovery protocol, because that is allowed to run on an
insecure ACL link.
Previously it was enough to reject a L2CAP connection during the
connection setup phase, but with Bluetooth 2.1 it is forbidden to
do any L2CAP protocol exchange on an insecure link (except SDP).
The new hci_conn_check_link_mode() function can be used to check the
integrity of an ACL link. This functions also takes care of the cases
where Security Mode 4 is disabled or one of the devices is based on
an older specification.
With the introduction of Security Mode 4 and Simple Pairing from the
Bluetooth 2.1 specification it became mandatory that the initiator
requires authentication and encryption before any L2CAP channel can
be established. The only exception here is PSM 1 for the service
discovery protocol (SDP). It is meant to be used without any encryption
since it contains only public information. This is how Bluetooth 2.0
and before handle connections on PSM 1.
For Bluetooth 2.1 devices the pairing procedure differentiates between
no bonding, general bonding and dedicated bonding. The L2CAP layer
wrongly uses always general bonding when creating new connections, but it
should not do this for SDP connections. In this case the authentication
requirement should be no bonding and the just-works model should be used,
but in case of non-SDP connection it is required to use general bonding.
If the new connection requires man-in-the-middle (MITM) protection, it
also first wrongly creates an unauthenticated link key and then later on
requests an upgrade to an authenticated link key to provide full MITM
protection. With Simple Pairing the link key generation is an expensive
operation (compared to Bluetooth 2.0 and before) and doing this twice
during a connection setup causes a noticeable delay when establishing
a new connection. This should be avoided to not regress from the expected
Bluetooth 2.0 connection times. The authentication requirements are known
up-front and so enforce them.
To fulfill these requirements the hci_connect() function has been extended
with an authentication requirement parameter that will be stored inside
the connection information and can be retrieved by userspace at any
time. This allows the correct IO capabilities exchange and results in
the expected behavior.
[Bluetooth] Fix reference counting during ACL config stage
The ACL config stage keeps holding a reference count on incoming
connections when requesting the extended features. This results in
keeping an ACL link up without any users. The problem here is that
the Bluetooth specification doesn't define an ownership of the ACL
link and thus it can happen that the implementation on the initiator
side doesn't care about disconnecting unused links. In this case the
acceptor needs to take care of this.
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6:
avr32: pm_standby low-power ram bug fix
avr32: Fix lockup after Java stack underflow in user mode
Code Review / linux-2.6.git / log