Commit Graph

288054 Commits

Author SHA1 Message Date
Benjamin Marzinski
58a7d5fb8e GFS2: call gfs2_write_alloc_required for each chunk
gfs2_fallocate was calling gfs2_write_alloc_required() once at the start of
the function. This caused problems since gfs2_write_alloc_required used a
long unsigned int for the len, but gfs2_fallocate could allocate a much
larger amount.  This patch will move the call into the loop where the
chunks are actually allocated and zeroed out. This will keep the allocation
size under the limit, and also allow gfs2_fallocate to quickly skip over
sections of the file that are already completely allocated.

fallcate_chunk was also not correctly setting the file size.  It was using the
len veriable to find the last block written to, but by the time it was setting
the size, the len variable had already been decremented to 0.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-09 15:29:10 +00:00
Steven Whitehouse
34cc1781c2 GFS2: Clean up log flush header writing
We already send both a pre and post flush to the block device
when writing a journal header. There is no need to wait for
the previous I/O specifically when we do this, unless we've
turned "barriers" off.

As a side effect, this also cleans up the code path for flushing
the journal and makes it more readable.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-09 14:07:06 +00:00
Steven Whitehouse
75ca61c101 GFS2: Remove a __GFP_NOFAIL allocation
In order to ensure that we've got enough buffer heads for flushing
the journal, the orignal code used __GFP_NOFAIL when performing
this allocation. Here we dispense with that in favour of using a
mempool. This should improve efficiency in low memory conditions
since flushing the journal is a good way to get memory back, we
don't want to be spinning, waiting on memory allocations. The
buffers which are allocated via this mempool are fairly short lived,
so that we'll recycle them pretty quickly.

Although there are other memory allocations which occur during the
journal flush process, this is the one which can potentially require
the most memory, so the most important one to fix.

The amount of memory reserved is a fixed amount, and we should not need
to scale it when there are a greater number of filesystems in use.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-08 12:10:23 +00:00
Steven Whitehouse
35e478f422 GFS2: Flush pending glock work when evicting an inode
This ensures that we will not try to access the inode thats
being flushed via the glock after it has been freed.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-07 10:43:02 +00:00
Bob Peterson
58884c4df0 GFS2: make sure rgrps are up to date in func gfs2_blk2rgrpd
This patch adds a call to gfs2_rindex_update from function gfs2_blk2rgrpd
and removes calls to it that are made redundant by it. The problem is
that a gfs2_grow can add rgrps to the rindex, then put those rgrps into
use, thus rendering the rindex we read in at mount time incomplete.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-05 15:10:34 +00:00
Bob Peterson
6aad1c3d3e GFS2: Eliminate sd_rindex_mutex
Over time, we've slowly eliminated the use of sd_rindex_mutex.
Up to this point, it was only used in two places: function
gfs2_ri_total (which totals the file system size by reading
and parsing the rindex file) and function gfs2_rindex_update
which updates the rgrps in memory. Both of these functions have
the rindex glock to protect them, so the rindex is unnecessary.
Since gfs2_grow writes to the rindex via the meta_fs, the mutex
is in the wrong order according to the normal rules. This patch
eliminates the mutex entirely to avoid the problem.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-05 15:06:56 +00:00
Bob Peterson
a08fd280b5 GFS2: Unlock rindex mutex on glock error
This patch fixes an error path in function gfs2_rindex_update
that leaves the rindex mutex held.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-03-01 09:25:21 +00:00
Steven Whitehouse
08728f2d8b GFS2: Make bd_cmp() static
Add missing static to bd_cmp()

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 17:11:27 +00:00
Bob Peterson
4a36d08d0d GFS2: Sort the ordered write list
This patch sorts the ordered write list for GFS2 writes.
This increases the throughput for simultaneous writes.
For example, if you have ten processes, all doing:
dd if=/dev/zero of=/mnt/gfs2/fileX
on different files, the throughput will be much better.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 17:10:53 +00:00
Steven Whitehouse
66fc061bda GFS2: FITRIM ioctl support
The FITRIM ioctl provides an alternative way to send discard requests to
the underlying device. Using the discard mount option results in every
freed block generating a discard request to the block device. This can
be slow, since many block devices can only process discard requests of
larger sizes, and also such operations can be time consuming.

Rather than using the discard mount option, FITRIM allows a sweep of the
filesystem on an occasional basis, and also to optionally avoid sending
down discard requests for smaller regions.

In GFS2 FITRIM will work at resource group granularity. There is a flag
for each resource group which keeps track of which resource groups have
been trimmed. This flag is reset whenever a deallocation occurs in the
resource group, and set whenever a successful FITRIM of that resource
group has taken place. This helps to reduce repeated discard requests
for the same block ranges, again improving performance.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 17:10:21 +00:00
Steven Whitehouse
47ac5537a7 GFS2: Move two functions from log.c to lops.c
gfs2_log_get_buf() and gfs2_log_fake_buf() are both used
only in lops.c, so move them next to their callers and they
can then become static.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 17:09:59 +00:00
Steven Whitehouse
a245769f25 GFS2: glock statistics gathering
The stats are divided into two sets: those relating to the
super block and those relating to an individual glock. The
super block stats are done on a per cpu basis in order to
try and reduce the overhead of gathering them. They are also
further divided by glock type.

In the case of both the super block and glock statistics,
the same information is gathered in each case. The super
block statistics are used to provide default values for
most of the glock statistics, so that newly created glocks
should have, as far as possible, a sensible starting point.

The statistics are divided into three pairs of mean and
variance, plus two counters. The mean/variance pairs are
smoothed exponential estimates and the algorithm used is
one which will be very familiar to those used to calculation
of round trip times in network code.

The three pairs of mean/variance measure the following
things:

 1. DLM lock time (non-blocking requests)
 2. DLM lock time (blocking requests)
 3. Inter-request time (again to the DLM)

A non-blocking request is one which will complete right
away, whatever the state of the DLM lock in question. That
currently means any requests when (a) the current state of
the lock is exclusive (b) the requested state is either null
or unlocked or (c) the "try lock" flag is set. A blocking
request covers all the other lock requests.

There are two counters. The first is there primarily to show
how many lock requests have been made, and thus how much data
has gone into the mean/variance calculations. The other counter
is counting queueing of holders at the top layer of the glock
code. Hopefully that number will be a lot larger than the number
of dlm lock requests issued.

So why gather these statistics? There are several reasons
we'd like to get a better idea of these timings:

1. To be able to better set the glock "min hold time"
2. To spot performance issues more easily
3. To improve the algorithm for selecting resource groups for
allocation (to base it on lock wait time, rather than blindly
using a "try lock")
Due to the smoothing action of the updates, a step change in
some input quantity being sampled will only fully be taken
into account after 8 samples (or 4 for the variance) and this
needs to be carefully considered when interpreting the
results.

Knowing both the time it takes a lock request to complete and
the average time between lock requests for a glock means we
can compute the total percentage of the time for which the
node is able to use a glock vs. time that the rest of the
cluster has its share. That will be very useful when setting
the lock min hold time.

The other point to remember is that all times are in
nanoseconds. Great care has been taken to ensure that we
measure exactly the quantities that we want, as accurately
as possible. There are always inaccuracies in any
measuring system, but I hope this is as accurate as we
can reasonably make it.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 17:09:42 +00:00
Linus Torvalds
891003abb0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes:
  GFS2: Read resource groups on mount
  GFS2: Ensure rindex is uptodate for fallocate
  GFS2: Read in rindex if necessary during unlink
  GFS2: Fix race between lru_list and glock ref count
2012-02-28 09:17:31 -08:00
Linus Torvalds
d5a74afd08 IOMMU fixes for Linux 3.3-rc5
All the fixes are for the OMAP IOMMU driver. The first patch is the
 biggest one. It fixes the calls of the function omap_find_iovm_area() in
 the omap-iommu-debug module which expects a 'struct device' parameter
 since commit fabdbca instead of an omap_iommu handle. The
 omap-iommu-debug code still passed the handle to the function which
 caused a crash.
 The second patch fixes a NULL pointer dereference in the OMAP code and
 the third patch makes sure that the omap-iommu is initialized before the
 omap-isp driver, which relies on the iommu. The last patch is only a
 workaround until defered probing is implemented.
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Merge tag 'iommu-fixes-v3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

IOMMU fixes for Linux 3.3-rc5

All the fixes are for the OMAP IOMMU driver. The first patch is the
biggest one. It fixes the calls of the function omap_find_iovm_area() in
the omap-iommu-debug module which expects a 'struct device' parameter
since commit fabdbca instead of an omap_iommu handle. The
omap-iommu-debug code still passed the handle to the function which
caused a crash.

The second patch fixes a NULL pointer dereference in the OMAP code and
the third patch makes sure that the omap-iommu is initialized before the
omap-isp driver, which relies on the iommu. The last patch is only a
workaround until defered probing is implemented.

* tag 'iommu-fixes-v3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  ARM: OMAP: make iommu subsys_initcall to fix builtin omap3isp
  iommu/omap: fix NULL pointer dereference
  iommu/omap: fix erroneous omap-iommu-debug API calls
2012-02-28 09:15:31 -08:00
Steven Whitehouse
a365fbf354 GFS2: Read resource groups on mount
This makes mount take slightly longer, but at the same time, the first
write to the filesystem will be faster too. It also means that if there
is a problem in the resource index, then we can refuse to mount rather
than having to try and report that when the first write occurs.

In addition, to avoid recursive locking, we hvae to take account of
instances when the rindex glock may already be held when we are
trying to update the rbtree of resource groups.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 09:52:39 +00:00
Bob Peterson
9e73f571ea GFS2: Ensure rindex is uptodate for fallocate
This patch fixes a problem whereby gfs2_grow was failing and causing GFS2
to assert. The problem was that when GFS2's fallocate operation tried to
acquire an "allocation" it made sure the rindex was up to date, and if not,
it called gfs2_rindex_update. However, if the file being fallocated was
the rindex itself, it was already locked at that point. By calling
gfs2_rindex_update at an earlier point in time, we bring rindex up to date
and thereby avoid trying to lock it when the "allocation" is acquired.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 09:48:30 +00:00
Bob Peterson
718b97bd6b GFS2: Read in rindex if necessary during unlink
This patch fixes a problem whereby you were unable to delete
files until other file system operations were done (such as
statfs, touch, writes, etc.) that caused the rindex to be
read in.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 09:48:02 +00:00
Steven Whitehouse
4043b886b0 GFS2: Fix race between lru_list and glock ref count
This patch fixes a narrow race window between the glock ref count
hitting zero and glocks being removed from the lru_list.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2012-02-28 09:43:07 +00:00
Linus Torvalds
586c6e7013 While demoing ktest at ELC in 2012, it was embarrassing that the
make_min_config test failed to work because the snowball board I was tesing
 it against had a config that would not build. But the make_min_config
 only tested the testing part and ignored build failures. The end result
 was a config file that would not boot.
 
 This time, for real.
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Merge tag 'ktest-fix-make-min-failed-build-for-real' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest

While demoing ktest at ELC in 2012, it was embarrassing that the
make_min_config test failed to work because the snowball board I was
testing it against had a config that would not build.  But the
make_min_config only tested the testing part and ignored build failures.
The end result was a config file that would not boot.

This time, for real.

* tag 'ktest-fix-make-min-failed-build-for-real' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest:
  ktest: Fix make_min_config test when build fails
2012-02-27 15:43:05 -08:00
Steven Rostedt
bf1c95abaf ktest: Fix make_min_config test when build fails
The make_min_config does not take into account when the build fails,
resulting in a invalid MIN_CONFIG .config file. When the build fails,
it is ignored and the boot test is executed, using the previous built
kernel. The configs that should be tested are not tested and they may
be added or removed depending on the result of the last kernel that
succeeded to be built.

If the build fails, mark the current config as a failure and the
configs that were disabled may still be needed.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-27 13:58:49 -05:00
Linus Torvalds
5ffca28a4a Merge git://git.kernel.org/pub/scm/linux/kernel/git/aia21/ntfs
Here are some trivial NTFS changes (a spelling fix and two use before
NULL check cases found by Coverity as well as an update in MAINTAINERS
for the path to the ntfs git repo) together with a simple LDM fix for
parsing fragmented VBLKs.

* git://git.kernel.org/pub/scm/linux/kernel/git/aia21/ntfs:
  NTFS: Update git repo path in MAINTAINERS file.
  LDM: Fix reassembly of extended VBLKs.
  NTFS: Correct two spelling errors "dealocate" to "deallocate" in mft.c.
  NTFS: Do not dereference pointer before checking for NULL.
  NTFS: Remove unused variable.
2012-02-27 07:59:33 -08:00
Linus Torvalds
e25bda5642 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/AMD: Fix UP build error
  x86: Specify a size for the cmp in the NMI handler
  x86/nmi: Test saved %cs in NMI to determine nested NMI case
  x86/amd: Fix L1i and L2 cache sharing information for AMD family 15h processors
  x86/microcode: Remove noisy AMD microcode warning
2012-02-27 07:55:51 -08:00
Linus Torvalds
70ca00db10 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/events: Revert trace_sched_stat_sleeptime()
2012-02-27 07:55:39 -08:00
Linus Torvalds
faf3502a3f Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Handle pending irqs in irq_startup()
  genirq: Unmask oneshot irqs when thread was not woken
2012-02-27 07:54:57 -08:00
Heiko Carstens
048cd4e51d compat: fix compile breakage on s390
The new is_compat_task() define for the !COMPAT case in
include/linux/compat.h conflicts with a similar define in
arch/s390/include/asm/compat.h.

This is the minimal patch which fixes the build issues.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-27 07:54:27 -08:00
Ohad Ben-Cohen
435792d934 ARM: OMAP: make iommu subsys_initcall to fix builtin omap3isp
omap3isp depends on omap's iommu and will fail to probe if
initialized before it (which always happen if they are builtin).

Make omap's iommu subsys_initcall as an interim solution until
the probe deferral mechanism is merged.

Reported-by: James <angweiyang@gmail.com>
Debugged-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: stable <stable@vger.kernel.org>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Hiroshi Doyu <hdoyu@nvidia.com>
Cc: Joerg Roedel <Joerg.Roedel@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-02-27 14:18:42 +01:00
Anton Altaparmakov
e6f4dee7a8 NTFS: Update git repo path in MAINTAINERS file.
Signed-off-by: Anton Altaparmakov <anton@tuxera.com>
2012-02-27 09:08:33 +00:00
Anton Altaparmakov
f621c53343 Merge branch 'master' of /Volumes/CaseSensitiveDisk/linux 2012-02-27 09:01:22 +00:00
Linus Torvalds
500dd2370e Two fixes to fix a memory corruption bug when WC pages never get
converted back to WB but end up being recycled in the general memory
 pool as WC.
 
 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Merge tag 'stable/for-linus-fixes-3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Two fixes to fix a memory corruption bug when WC pages never get
converted back to WB but end up being recycled in the general memory
pool as WC.

There is a better way of fixing this, but there is not enough time to do
the full benchmarking to pick one of the right options - so picking the
one that favors stability for right now.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

* tag 'stable/for-linus-fixes-3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/pat: Disable PAT support for now.
  xen/setup: Remove redundant filtering of PTE masks.
2012-02-26 21:03:16 -08:00
Linus Torvalds
f6bd5798f3 Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1
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Merge tag 'for-linus' of git://github.com/rustyrussell/linux

* tag 'for-linus' of git://github.com/rustyrussell/linux:
  mod/file2alias: make modpost compile on darwin again
2012-02-26 21:02:07 -08:00
Ian Kent
f694fc9729 autofs4 - update MAINTAINERS mailing list entry
The autofs mailing list has moved to vger.kernel.org.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-26 21:01:37 -08:00
Andreas Bießmann
dd2a3acaec mod/file2alias: make modpost compile on darwin again
commit e49ce14150 breaks cross compiling
the linux kernel on darwin hosts.
This fix introduce some minimal glue to adopt linker section handling
for darwin hosts.

Signed-off-by: Andreas Bießmann <andreas@biessmann.de>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Jochen Friedrich <jochen@scram.de>
CC: Samuel Ortiz <sameo@linux.intel.com>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Bernhard Walle <bernhard@bwalle.de>
2012-02-27 10:29:31 +10:30
Linus Torvalds
203738e548 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
1) ICMP sockets leave err uninitialized but we try to return it for the
   unsupported MSG_OOB case, reported by Dave Jones.

2) Add new Zaurus device ID entries, from Dave Jones.

3) Pointer calculation in hso driver memset is wrong, from Dan
   Carpenter.

4) ks8851_probe() checks unsigned value as negative, fix also from Dan
   Carpenter.

5) Fix crashes in atl1c driver due to TX queue handling, from Eric
   Dumazet.  I anticipate some TX side locking fixes coming in the near
   future for this driver as well.

6) The inline directive fix in Bluetooth which was breaking the build
   only with very new versions of GCC, from Johan Hedberg.

7) Fix crashes in the ATP CLIP code due to ARP cleanups this merge
   window, reported by Meelis Roos and fixed by Eric Dumazet.

8) JME driver doesn't flush RX FIFO correctly, from Guo-Fu Tseng.

9) Some ip6_route_output() callers test the return value for NULL, but
   this never happens as the convention is to return a dst entry with
   dst->error set.  Fixes from RonQing Li.

10) Logitech Harmony 900 should be handled by zaurus driver not
   cdc_ether, update white lists and black lists accordingly.  From
   Scott Talbert.

11) Receiving from certain kinds of devices there won't be a MAC header,
   so there is no MAC header to fixup in the IPSEC code, and if we try
   to do it we'll crash.  Fix from Eric Dumazet.

12) Port type array indexing off-by-one in mlx4 driver, fix from Yevgeny
   Petrilin.

13) Fix regression in link-down handling in davinci_emac which causes
   all RX descriptors to be freed up and therefore RX to wedge
   completely, from Christian Riesch.

14) It took two attempts, but ctnetlink soft lockups seem to be
   cured now, from Pablo Neira Ayuso.

15) Endianness bug fix in ENIC driver, from Santosh Nayak.

16) The long ago conversion of the PPP fragmentation code over to
   abstracted SKB list handling wasn't perfect, once we get an
   out of sequence SKB we don't flush the rest of them like we
   should.  From Ben McKeegan.

17) Fix regression of ->ip_summed initialization in sfc driver.
   From Ben Hutchings.

18) Bluetooth timeout mistakenly using msecs instead of jiffies,
   from Andrzej Kaczmarek.

19) Using _sync variant of work cancellation results in deadlocks,
   use the non _sync variants instead.  From Andre Guedes.

20) Bluetooth rfcomm code had reference counting problems leading
   to crashes, fix from Octavian Purdila.

21) The conversion of netem over to classful qdisc handling added
   two bugs to netem_dequeue(), fixes from Eric Dumazet.

22) Missing pci_iounmap() in ATM Solos driver.  Fix from Julia Lawall.

23) b44_pci_exit() should not have __exit tag since it's invoked from
   non-__exit code.  From Nikola Pajkovsky.

24) The conversion of the neighbour hash tables over to RCU added a
   race, fixed here by adding the necessary reread of tbl->nht, fix
   from Michel Machado.

25) When we added VF (virtual function) attributes for network device
   dumps, this potentially bloats up the size of the dump of one
   network device such that the dump size is too large for the buffer
   allocated by properly written netlink applications.

   In particular, if you add 255 VFs to a network device, parts of
   GLIBC stop working.

   To fix this, we add an attribute that is used to turn on these
   extended portions of the network device dump.  Sophisticaed
   applications like 'ip' that want to see this stuff  will be changed
   to set the attribute, whereas things like GLIBC that don't care
   about VFs simply will not, and therefore won't be busted by the
   mere presence of VFs on a network device.

   Thanks to the tireless work of Greg Rose on this fix.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (53 commits)
  sfc: Fix assignment of ip_summed for pre-allocated skbs
  ppp: fix 'ppp_mp_reconstruct bad seq' errors
  enic: Fix endianness bug.
  gre: fix spelling in comments
  netfilter: ctnetlink: fix soft lockup when netlink adds new entries (v2)
  Revert "netfilter: ctnetlink: fix soft lockup when netlink adds new entries"
  davinci_emac: Do not free all rx dma descriptors during init
  mlx4_core: Fixing array indexes when setting port types
  phy: IC+101G and PHY_HAS_INTERRUPT flag
  netdev/phy/icplus: Correct broken phy_init code
  ipsec: be careful of non existing mac headers
  Move Logitech Harmony 900 from cdc_ether to zaurus
  hso: memsetting wrong data in hso_get_count()
  netfilter: ip6_route_output() never returns NULL.
  ethernet/broadcom: ip6_route_output() never returns NULL.
  ipv6: ip6_route_output() never returns NULL.
  jme: Fix FIFO flush issue
  atm: clip: remove clip_tbl
  ipv4: ping: Fix recvmsg MSG_OOB error handling.
  rtnetlink: Fix problem with buffer allocation
  ...
2012-02-26 12:47:17 -08:00
Linus Torvalds
3c761ea05a Fix autofs compile without CONFIG_COMPAT
The autofs compat handling fix caused a compile failure when
CONFIG_COMPAT isn't defined.

Instead of adding random #ifdef'fery in autofs, let's just make the
compat helpers earlier to use: without CONFIG_COMPAT, is_compat_task()
just hardcodes to zero.

We could probably do something similar for a number of other cases where
we have #ifdef's in code, but this is the low-hanging fruit.

Reported-and-tested-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-26 09:44:55 -08:00
Linus Torvalds
6b21d18ed5 Linux 3.3-rc5 2012-02-25 12:18:16 -08:00
Linus Torvalds
00b10ecf2d Couple of minor driver fixes.
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Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Couple of minor driver fixes.

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (max34440) Fix resetting temperature history
  hwmon: (f75375s) Fix register write order when setting fans to full speed
  hwmon: (ads1015) Fix file leak in probe function
  hwmon: (max6639) Fix PPR register initialization to set both channels
  hwmon: (max6639) Fix FAN_FROM_REG calculation
2012-02-25 12:12:08 -08:00
Linus Torvalds
1e73fde581 Merge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
three kbuild fixes for 3.3:
 - make deb-pkg symlink race fix.
 - make coccicheck fix.
 - Dropping the check for modutils.  This is not a regression, but
   allows the module-init-tools replacement kmod work with the 3.3
   kernel.

* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  coccicheck: change handling of C={1,2} when M= is set
  builddeb: Don't create files in /tmp with predictable names
  kbuild: do not check for ancient modutils tools
2012-02-25 12:11:25 -08:00
Ian Kent
a32744d4ab autofs: work around unhappy compat problem on x86-64
When the autofs protocol version 5 packet type was added in commit
5c0a32fc2c ("autofs4: add new packet type for v5 communications"), it
obvously tried quite hard to be word-size agnostic, and uses explicitly
sized fields that are all correctly aligned.

However, with the final "char name[NAME_MAX+1]" array at the end, the
actual size of the structure ends up being not very well defined:
because the struct isn't marked 'packed', doing a "sizeof()" on it will
align the size of the struct up to the biggest alignment of the members
it has.

And despite all the members being the same, the alignment of them is
different: a "__u64" has 4-byte alignment on x86-32, but native 8-byte
alignment on x86-64.  And while 'NAME_MAX+1' ends up being a nice round
number (256), the name[] array starts out a 4-byte aligned.

End result: the "packed" size of the structure is 300 bytes: 4-byte, but
not 8-byte aligned.

As a result, despite all the fields being in the same place on all
architectures, sizeof() will round up that size to 304 bytes on
architectures that have 8-byte alignment for u64.

Note that this is *not* a problem for 32-bit compat mode on POWER, since
there __u64 is 8-byte aligned even in 32-bit mode.  But on x86, 32-bit
and 64-bit alignment is different for 64-bit entities, and as a result
the structure that has exactly the same layout has different sizes.

So on x86-64, but no other architecture, we will just subtract 4 from
the size of the structure when running in a compat task.  That way we
will write the properly sized packet that user mode expects.

Not pretty.  Sadly, this very subtle, and unnecessary, size difference
has been encoded in user space that wants to read packets of *exactly*
the right size, and will refuse to touch anything else.

Reported-and-tested-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-25 12:10:27 -08:00
Linus Torvalds
b52b80023f One InfiniBand/RDMA regression fix for 3.3:
- mlx4 SR-IOV changes added static exported functions, which doesn't
    build on powerpc at least.  Fix from Doug Ledford for this.
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Merge tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband

One InfiniBand/RDMA regression fix for 3.3:

 - mlx4 SR-IOV changes added static exported functions, which doesn't
   build on powerpc at least.  Fix from Doug Ledford for this.

* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  mlx4_core: Exported functions can't be static
2012-02-24 20:03:14 -08:00
David S. Miller
b072342e26 Merge branch 'sfc-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/bwh/sfc 2012-02-24 22:12:44 -05:00
Ben Hutchings
ff3bc1e752 sfc: Fix assignment of ip_summed for pre-allocated skbs
When pre-allocating skbs for received packets, we set ip_summed =
CHECKSUM_UNNCESSARY.  We used to change it back to CHECKSUM_NONE when
the received packet had an incorrect checksum or unhandled protocol.

Commit bc8acf2c8c ('drivers/net: avoid
some skb->ip_summed initializations') mistakenly replaced the latter
assignment with a DEBUG-only assertion that ip_summed ==
CHECKSUM_NONE.  This assertion is always false, but it seems no-one
has exercised this code path in a DEBUG build.

Fix this by moving our assignment of CHECKSUM_UNNECESSARY into
efx_rx_packet_gro().

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-02-25 00:10:22 +00:00
Linus Torvalds
16bca1d572 SCSI fixes on 20120224
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6

SCSI fixes on 20120224:
 "This is a set of assorted bug fixes for power management, mpt2sas,
  ipr, the rdac device handler and quite a big chunk for qla2xxx (plus a
  use after free of scsi_host in scsi_scan.c). "

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] scsi_dh_rdac: Fix for unbalanced reference count
  [SCSI] scsi_pm: Fix bug in the SCSI power management handler
  [SCSI] scsi_scan: Fix 'Poison overwritten' warning caused by using freed 'shost'
  [SCSI] qla2xxx: Update version number to 8.03.07.13-k.
  [SCSI] qla2xxx: Proper detection of firmware abort error code for ISP82xx.
  [SCSI] qla2xxx: Remove resetting memory during device initialization for ISP82xx.
  [SCSI] qla2xxx: Complete mailbox command timedout to avoid initialization failures during next reset cycle.
  [SCSI] qla2xxx: Remove check for null fcport from host reset handler.
  [SCSI] qla2xxx: Correct out of bounds read of ISP2200 mailbox registers.
  [SCSI] qla2xxx: Remove errant clearing of MBX_INTERRUPT flag during CT-IOCB processing.
  [SCSI] qla2xxx: Clear options-flags while issuing stop-firmware mbx command.
  [SCSI] qla2xxx: Add an "is reset active" helper.
  [SCSI] qla2xxx: Add check for null fcport references in qla2xxx_queuecommand.
  [SCSI] qla2xxx: Propagate up abort failures.
  [SCSI] isci: Fix NULL ptr dereference when no firmware is being loaded
  [SCSI] ipr: fix eeh recovery for 64-bit adapters
  [SCSI] mpt2sas: Fix mismatch in mpt2sas_base_hard_reset_handler() mutex lock-unlock
2012-02-24 16:08:51 -08:00
Ben McKeegan
8a49ad6e89 ppp: fix 'ppp_mp_reconstruct bad seq' errors
This patch fixes a (mostly cosmetic) bug introduced by the patch
'ppp: Use SKB queue abstraction interfaces in fragment processing'
found here: http://www.spinics.net/lists/netdev/msg153312.html

The above patch rewrote and moved the code responsible for cleaning
up discarded fragments but the new code does not catch every case
where this is necessary.  This results in some discarded fragments
remaining in the queue, and triggering a 'bad seq' error on the
subsequent call to ppp_mp_reconstruct.  Fragments are discarded
whenever other fragments of the same frame have been lost.
This can generate a lot of unwanted and misleading log messages.

This patch also adds additional detail to the debug logging to
make it clearer which fragments were lost and which other fragments
were discarded as a result of losses. (Run pppd with 'kdebug 1'
option to enable debug logging.)

Signed-off-by: Ben McKeegan <ben@netservers.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-24 17:53:21 -05:00
Santosh Nayak
21ca54e99b enic: Fix endianness bug.
Sparse complaints the endian bug.

Signed-off-by: Santosh Nayak <santoshprasadnayak@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-24 17:53:03 -05:00
Greg Dietsche
42f1c01b79 coccicheck: change handling of C={1,2} when M= is set
This patch reverts a portion of d0bc1fb4 so that coccicheck will
work properly when C=1 or C=2.

Reported-and-tested-by: Brice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: Greg Dietsche <Gregory.Dietsche@cuw.edu>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-02-24 23:50:19 +01:00
David S. Miller
e807e566e9 Merge branch 'master' of git://1984.lsi.us.es/net 2012-02-24 17:41:57 -05:00
stephen hemminger
bff528578f gre: fix spelling in comments
The original spelling and bad word choice makes these comments hard to read.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-24 17:41:11 -05:00
Linus Torvalds
e98092bedc Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] hdpvr: update picture controls to support firmware versions > 0.15
  [media] wl128x: fix build errors when GPIOLIB is not enabled
  [media] hdpvr: fix race conditon during start of streaming
  [media] omap3isp: Fix crash caused by subdevs now having a pointer to devnodes
  [media] imon: don't wedge hardware after early callbacks
2012-02-24 12:32:51 -08:00
Oleg Nesterov
971316f050 epoll: ep_unregister_pollwait() can use the freed pwq->whead
signalfd_cleanup() ensures that ->signalfd_wqh is not used, but
this is not enough. eppoll_entry->whead still points to the memory
we are going to free, ep_unregister_pollwait()->remove_wait_queue()
is obviously unsafe.

Change ep_poll_callback(POLLFREE) to set eppoll_entry->whead = NULL,
change ep_unregister_pollwait() to check pwq->whead != NULL under
rcu_read_lock() before remove_wait_queue(). We add the new helper,
ep_remove_wait_queue(), for this.

This works because sighand_cachep is SLAB_DESTROY_BY_RCU and because
->signalfd_wqh is initialized in sighand_ctor(), not in copy_sighand.
ep_unregister_pollwait()->remove_wait_queue() can play with already
freed and potentially reused ->sighand, but this is fine. This memory
must have the valid ->signalfd_wqh until rcu_read_unlock().

Reported-by: Maxime Bizon <mbizon@freebox.fr>
Cc: <stable@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-24 11:42:50 -08:00
Oleg Nesterov
d80e731eca epoll: introduce POLLFREE to flush ->signalfd_wqh before kfree()
This patch is intentionally incomplete to simplify the review.
It ignores ep_unregister_pollwait() which plays with the same wqh.
See the next change.

epoll assumes that the EPOLL_CTL_ADD'ed file controls everything
f_op->poll() needs. In particular it assumes that the wait queue
can't go away until eventpoll_release(). This is not true in case
of signalfd, the task which does EPOLL_CTL_ADD uses its ->sighand
which is not connected to the file.

This patch adds the special event, POLLFREE, currently only for
epoll. It expects that init_poll_funcptr()'ed hook should do the
necessary cleanup. Perhaps it should be defined as EPOLLFREE in
eventpoll.

__cleanup_sighand() is changed to do wake_up_poll(POLLFREE) if
->signalfd_wqh is not empty, we add the new signalfd_cleanup()
helper.

ep_poll_callback(POLLFREE) simply does list_del_init(task_list).
This make this poll entry inconsistent, but we don't care. If you
share epoll fd which contains our sigfd with another process you
should blame yourself. signalfd is "really special". I simply do
not know how we can define the "right" semantics if it used with
epoll.

The main problem is, epoll calls signalfd_poll() once to establish
the connection with the wait queue, after that signalfd_poll(NULL)
returns the different/inconsistent results depending on who does
EPOLL_CTL_MOD/signalfd_read/etc. IOW: apart from sigmask, signalfd
has nothing to do with the file, it works with the current thread.

In short: this patch is the hack which tries to fix the symptoms.
It also assumes that nobody can take tasklist_lock under epoll
locks, this seems to be true.

Note:

	- we do not have wake_up_all_poll() but wake_up_poll()
	  is fine, poll/epoll doesn't use WQ_FLAG_EXCLUSIVE.

	- signalfd_cleanup() uses POLLHUP along with POLLFREE,
	  we need a couple of simple changes in eventpoll.c to
	  make sure it can't be "lost".

Reported-by: Maxime Bizon <mbizon@freebox.fr>
Cc: <stable@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-24 11:42:50 -08:00