<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/kernel, branch v3.13-rc2</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge branch 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq</title>
<updated>2013-11-29T17:49:08+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-11-29T17:49:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7224b31bd5f5a8994f8fb2d540847213a50db28c'/>
<id>7224b31bd5f5a8994f8fb2d540847213a50db28c</id>
<content type='text'>
Pull workqueue fixes from Tejun Heo:
 "This contains one important fix.  The NUMA support added a while back
  broke ordering guarantees on ordered workqueues.  It was enforced by
  having single frontend interface with @max_active == 1 but the NUMA
  support puts multiple interfaces on unbound workqueues on NUMA
  machines thus breaking the ordered guarantee.  This is fixed by
  disabling NUMA support on ordered workqueues.

  The above and a couple other patches were sitting in for-3.12-fixes
  but I forgot to push that out, so they ended up waiting a bit too
  long.  My aplogies.

  Other fixes are minor"

* 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix pool ID allocation leakage and remove BUILD_BUG_ON() in init_workqueues
  workqueue: fix comment typo for __queue_work()
  workqueue: fix ordered workqueues in NUMA setups
  workqueue: swap set_cpus_allowed_ptr() and PF_NO_SETAFFINITY
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull workqueue fixes from Tejun Heo:
 "This contains one important fix.  The NUMA support added a while back
  broke ordering guarantees on ordered workqueues.  It was enforced by
  having single frontend interface with @max_active == 1 but the NUMA
  support puts multiple interfaces on unbound workqueues on NUMA
  machines thus breaking the ordered guarantee.  This is fixed by
  disabling NUMA support on ordered workqueues.

  The above and a couple other patches were sitting in for-3.12-fixes
  but I forgot to push that out, so they ended up waiting a bit too
  long.  My aplogies.

  Other fixes are minor"

* 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix pool ID allocation leakage and remove BUILD_BUG_ON() in init_workqueues
  workqueue: fix comment typo for __queue_work()
  workqueue: fix ordered workqueues in NUMA setups
  workqueue: swap set_cpus_allowed_ptr() and PF_NO_SETAFFINITY
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup</title>
<updated>2013-11-29T17:47:06+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-11-29T17:47:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2855987d13d2de99eb337cae98f5656e93452617'/>
<id>2855987d13d2de99eb337cae98f5656e93452617</id>
<content type='text'>
Pull cgroup fixes from Tejun Heo:
 "Fixes for three issues.

   - cgroup destruction path could swamp system_wq possibly leading to
     deadlock.  This actually seems to happen in the wild with memcg
     because memcg destruction path adds nested dependency on system_wq.

     Resolved by isolating cgroup destruction work items on its
     dedicated workqueue.

   - Possible locking context deadlock through seqcount reported by
     lockdep

   - Memory leak under certain conditions"

* 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix cgroup_subsys_state leak for seq_files
  cpuset: Fix memory allocator deadlock
  cgroup: use a dedicated workqueue for cgroup destruction
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull cgroup fixes from Tejun Heo:
 "Fixes for three issues.

   - cgroup destruction path could swamp system_wq possibly leading to
     deadlock.  This actually seems to happen in the wild with memcg
     because memcg destruction path adds nested dependency on system_wq.

     Resolved by isolating cgroup destruction work items on its
     dedicated workqueue.

   - Possible locking context deadlock through seqcount reported by
     lockdep

   - Memory leak under certain conditions"

* 'for-3.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix cgroup_subsys_state leak for seq_files
  cpuset: Fix memory allocator deadlock
  cgroup: use a dedicated workqueue for cgroup destruction
</pre>
</div>
</content>
</entry>
<entry>
<title>kernel/extable: fix address-checks for core_kernel and init areas</title>
<updated>2013-11-28T17:49:41+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2013-11-28T08:16:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5ecbe3c3c690b5ab493c730c317475287a9e8b45'/>
<id>5ecbe3c3c690b5ab493c730c317475287a9e8b45</id>
<content type='text'>
The init_kernel_text() and core_kernel_text() functions should not
include the labels _einittext and _etext when checking if an address is
inside the .text or .init sections.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The init_kernel_text() and core_kernel_text() functions should not
include the labels _einittext and _etext when checking if an address is
inside the .text or .init sections.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cgroup: fix cgroup_subsys_state leak for seq_files</title>
<updated>2013-11-27T23:16:21+00:00</updated>
<author>
<name>Tejun Heo</name>
<email>tj@kernel.org</email>
</author>
<published>2013-11-27T23:16:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e605b36575e896edd8161534550c9ea021b03bc0'/>
<id>e605b36575e896edd8161534550c9ea021b03bc0</id>
<content type='text'>
If a cgroup file implements either read_map() or read_seq_string(),
such file is served using seq_file by overriding file-&gt;f_op to
cgroup_seqfile_operations, which also overrides the release method to
single_release() from cgroup_file_release().

Because cgroup_file_open() didn't use to acquire any resources, this
used to be fine, but since f7d58818ba42 ("cgroup: pin
cgroup_subsys_state when opening a cgroupfs file"), cgroup_file_open()
pins the css (cgroup_subsys_state) which is put by
cgroup_file_release().  The patch forgot to update the release path
for seq_files and each open/release cycle leaks a css reference.

Fix it by updating cgroup_file_release() to also handle seq_files and
using it for seq_file release path too.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Cc: stable@vger.kernel.org # v3.12
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If a cgroup file implements either read_map() or read_seq_string(),
such file is served using seq_file by overriding file-&gt;f_op to
cgroup_seqfile_operations, which also overrides the release method to
single_release() from cgroup_file_release().

Because cgroup_file_open() didn't use to acquire any resources, this
used to be fine, but since f7d58818ba42 ("cgroup: pin
cgroup_subsys_state when opening a cgroupfs file"), cgroup_file_open()
pins the css (cgroup_subsys_state) which is put by
cgroup_file_release().  The patch forgot to update the release path
for seq_files and each open/release cycle leaks a css reference.

Fix it by updating cgroup_file_release() to also handle seq_files and
using it for seq_file release path too.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Cc: stable@vger.kernel.org # v3.12
</pre>
</div>
</content>
</entry>
<entry>
<title>cpuset: Fix memory allocator deadlock</title>
<updated>2013-11-27T18:52:47+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2013-11-26T14:03:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=0fc0287c9ed1ffd3706f8b4d9b314aa102ef1245'/>
<id>0fc0287c9ed1ffd3706f8b4d9b314aa102ef1245</id>
<content type='text'>
Juri hit the below lockdep report:

[    4.303391] ======================================================
[    4.303392] [ INFO: SOFTIRQ-safe -&gt; SOFTIRQ-unsafe lock order detected ]
[    4.303394] 3.12.0-dl-peterz+ #144 Not tainted
[    4.303395] ------------------------------------------------------
[    4.303397] kworker/u4:3/689 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[    4.303399]  (&amp;p-&gt;mems_allowed_seq){+.+...}, at: [&lt;ffffffff8114e63c&gt;] new_slab+0x6c/0x290
[    4.303417]
[    4.303417] and this task is already holding:
[    4.303418]  (&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock){..-...}, at: [&lt;ffffffff812d2dfb&gt;] blk_execute_rq_nowait+0x5b/0x100
[    4.303431] which would create a new lock dependency:
[    4.303432]  (&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock){..-...} -&gt; (&amp;p-&gt;mems_allowed_seq){+.+...}
[    4.303436]

[    4.303898] the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock:
[    4.303918] -&gt; (&amp;p-&gt;mems_allowed_seq){+.+...} ops: 2762 {
[    4.303922]    HARDIRQ-ON-W at:
[    4.303923]                     [&lt;ffffffff8108ab9a&gt;] __lock_acquire+0x65a/0x1ff0
[    4.303926]                     [&lt;ffffffff8108cbe3&gt;] lock_acquire+0x93/0x140
[    4.303929]                     [&lt;ffffffff81063dd6&gt;] kthreadd+0x86/0x180
[    4.303931]                     [&lt;ffffffff816ded6c&gt;] ret_from_fork+0x7c/0xb0
[    4.303933]    SOFTIRQ-ON-W at:
[    4.303933]                     [&lt;ffffffff8108abcc&gt;] __lock_acquire+0x68c/0x1ff0
[    4.303935]                     [&lt;ffffffff8108cbe3&gt;] lock_acquire+0x93/0x140
[    4.303940]                     [&lt;ffffffff81063dd6&gt;] kthreadd+0x86/0x180
[    4.303955]                     [&lt;ffffffff816ded6c&gt;] ret_from_fork+0x7c/0xb0
[    4.303959]    INITIAL USE at:
[    4.303960]                    [&lt;ffffffff8108a884&gt;] __lock_acquire+0x344/0x1ff0
[    4.303963]                    [&lt;ffffffff8108cbe3&gt;] lock_acquire+0x93/0x140
[    4.303966]                    [&lt;ffffffff81063dd6&gt;] kthreadd+0x86/0x180
[    4.303969]                    [&lt;ffffffff816ded6c&gt;] ret_from_fork+0x7c/0xb0
[    4.303972]  }

Which reports that we take mems_allowed_seq with interrupts enabled. A
little digging found that this can only be from
cpuset_change_task_nodemask().

This is an actual deadlock because an interrupt doing an allocation will
hit get_mems_allowed()-&gt;...-&gt;__read_seqcount_begin(), which will spin
forever waiting for the write side to complete.

Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Reported-by: Juri Lelli &lt;juri.lelli@gmail.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Tested-by: Juri Lelli &lt;juri.lelli@gmail.com&gt;
Acked-by: Li Zefan &lt;lizefan@huawei.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Cc: stable@vger.kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Juri hit the below lockdep report:

[    4.303391] ======================================================
[    4.303392] [ INFO: SOFTIRQ-safe -&gt; SOFTIRQ-unsafe lock order detected ]
[    4.303394] 3.12.0-dl-peterz+ #144 Not tainted
[    4.303395] ------------------------------------------------------
[    4.303397] kworker/u4:3/689 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[    4.303399]  (&amp;p-&gt;mems_allowed_seq){+.+...}, at: [&lt;ffffffff8114e63c&gt;] new_slab+0x6c/0x290
[    4.303417]
[    4.303417] and this task is already holding:
[    4.303418]  (&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock){..-...}, at: [&lt;ffffffff812d2dfb&gt;] blk_execute_rq_nowait+0x5b/0x100
[    4.303431] which would create a new lock dependency:
[    4.303432]  (&amp;(&amp;q-&gt;__queue_lock)-&gt;rlock){..-...} -&gt; (&amp;p-&gt;mems_allowed_seq){+.+...}
[    4.303436]

[    4.303898] the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock:
[    4.303918] -&gt; (&amp;p-&gt;mems_allowed_seq){+.+...} ops: 2762 {
[    4.303922]    HARDIRQ-ON-W at:
[    4.303923]                     [&lt;ffffffff8108ab9a&gt;] __lock_acquire+0x65a/0x1ff0
[    4.303926]                     [&lt;ffffffff8108cbe3&gt;] lock_acquire+0x93/0x140
[    4.303929]                     [&lt;ffffffff81063dd6&gt;] kthreadd+0x86/0x180
[    4.303931]                     [&lt;ffffffff816ded6c&gt;] ret_from_fork+0x7c/0xb0
[    4.303933]    SOFTIRQ-ON-W at:
[    4.303933]                     [&lt;ffffffff8108abcc&gt;] __lock_acquire+0x68c/0x1ff0
[    4.303935]                     [&lt;ffffffff8108cbe3&gt;] lock_acquire+0x93/0x140
[    4.303940]                     [&lt;ffffffff81063dd6&gt;] kthreadd+0x86/0x180
[    4.303955]                     [&lt;ffffffff816ded6c&gt;] ret_from_fork+0x7c/0xb0
[    4.303959]    INITIAL USE at:
[    4.303960]                    [&lt;ffffffff8108a884&gt;] __lock_acquire+0x344/0x1ff0
[    4.303963]                    [&lt;ffffffff8108cbe3&gt;] lock_acquire+0x93/0x140
[    4.303966]                    [&lt;ffffffff81063dd6&gt;] kthreadd+0x86/0x180
[    4.303969]                    [&lt;ffffffff816ded6c&gt;] ret_from_fork+0x7c/0xb0
[    4.303972]  }

Which reports that we take mems_allowed_seq with interrupts enabled. A
little digging found that this can only be from
cpuset_change_task_nodemask().

This is an actual deadlock because an interrupt doing an allocation will
hit get_mems_allowed()-&gt;...-&gt;__read_seqcount_begin(), which will spin
forever waiting for the write side to complete.

Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Reported-by: Juri Lelli &lt;juri.lelli@gmail.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Tested-by: Juri Lelli &lt;juri.lelli@gmail.com&gt;
Acked-by: Li Zefan &lt;lizefan@huawei.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Cc: stable@vger.kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'trace-fixes-v3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2013-11-27T02:04:21+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-11-27T02:04:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8ae516aa8b8161254d3e402b3348b2a9b8d1efd0'/>
<id>8ae516aa8b8161254d3e402b3348b2a9b8d1efd0</id>
<content type='text'>
Pull tracing fixes from Steven Rostedt:
 "This includes two fixes.

  1) is a bug fix that happens when root does the following:

     echo function_graph &gt; current_tracer
     modprobe foo
     echo nop &gt; current_tracer

   This causes the ftrace internal accounting to get screwed up and
   crashes ftrace, preventing the user from using the function tracer
   after that.

  2) if a TRACE_EVENT has a string field, and NULL is given for it.

   The internal trace event code does a strlen() and strcpy() on the
   source of field.  If it is NULL it causes the system to oops.

   This bug has been there since 2.6.31, but no TRACE_EVENT ever passed
   in a NULL to the string field, until now"

* tag 'trace-fixes-v3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix function graph with loading of modules
  tracing: Allow events to have NULL strings
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull tracing fixes from Steven Rostedt:
 "This includes two fixes.

  1) is a bug fix that happens when root does the following:

     echo function_graph &gt; current_tracer
     modprobe foo
     echo nop &gt; current_tracer

   This causes the ftrace internal accounting to get screwed up and
   crashes ftrace, preventing the user from using the function tracer
   after that.

  2) if a TRACE_EVENT has a string field, and NULL is given for it.

   The internal trace event code does a strlen() and strcpy() on the
   source of field.  If it is NULL it causes the system to oops.

   This bug has been there since 2.6.31, but no TRACE_EVENT ever passed
   in a NULL to the string field, until now"

* tag 'trace-fixes-v3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix function graph with loading of modules
  tracing: Allow events to have NULL strings
</pre>
</div>
</content>
</entry>
<entry>
<title>ftrace: Fix function graph with loading of modules</title>
<updated>2013-11-26T15:36:50+00:00</updated>
<author>
<name>Steven Rostedt (Red Hat)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2013-11-26T01:59:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8a56d7761d2d041ae5e8215d20b4167d8aa93f51'/>
<id>8a56d7761d2d041ae5e8215d20b4167d8aa93f51</id>
<content type='text'>
Commit 8c4f3c3fa9681 "ftrace: Check module functions being traced on reload"
fixed module loading and unloading with respect to function tracing, but
it missed the function graph tracer. If you perform the following

 # cd /sys/kernel/debug/tracing
 # echo function_graph &gt; current_tracer
 # modprobe nfsd
 # echo nop &gt; current_tracer

You'll get the following oops message:

 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 2910 at /linux.git/kernel/trace/ftrace.c:1640 __ftrace_hash_rec_update.part.35+0x168/0x1b9()
 Modules linked in: nfsd exportfs nfs_acl lockd ipt_MASQUERADE sunrpc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables uinput snd_hda_codec_idt
 CPU: 2 PID: 2910 Comm: bash Not tainted 3.13.0-rc1-test #7
 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007
  0000000000000668 ffff8800787efcf8 ffffffff814fe193 ffff88007d500000
  0000000000000000 ffff8800787efd38 ffffffff8103b80a 0000000000000668
  ffffffff810b2b9a ffffffff81a48370 0000000000000001 ffff880037aea000
 Call Trace:
  [&lt;ffffffff814fe193&gt;] dump_stack+0x4f/0x7c
  [&lt;ffffffff8103b80a&gt;] warn_slowpath_common+0x81/0x9b
  [&lt;ffffffff810b2b9a&gt;] ? __ftrace_hash_rec_update.part.35+0x168/0x1b9
  [&lt;ffffffff8103b83e&gt;] warn_slowpath_null+0x1a/0x1c
  [&lt;ffffffff810b2b9a&gt;] __ftrace_hash_rec_update.part.35+0x168/0x1b9
  [&lt;ffffffff81502f89&gt;] ? __mutex_lock_slowpath+0x364/0x364
  [&lt;ffffffff810b2cc2&gt;] ftrace_shutdown+0xd7/0x12b
  [&lt;ffffffff810b47f0&gt;] unregister_ftrace_graph+0x49/0x78
  [&lt;ffffffff810c4b30&gt;] graph_trace_reset+0xe/0x10
  [&lt;ffffffff810bf393&gt;] tracing_set_tracer+0xa7/0x26a
  [&lt;ffffffff810bf5e1&gt;] tracing_set_trace_write+0x8b/0xbd
  [&lt;ffffffff810c501c&gt;] ? ftrace_return_to_handler+0xb2/0xde
  [&lt;ffffffff811240a8&gt;] ? __sb_end_write+0x5e/0x5e
  [&lt;ffffffff81122aed&gt;] vfs_write+0xab/0xf6
  [&lt;ffffffff8150a185&gt;] ftrace_graph_caller+0x85/0x85
  [&lt;ffffffff81122dbd&gt;] SyS_write+0x59/0x82
  [&lt;ffffffff8150a185&gt;] ftrace_graph_caller+0x85/0x85
  [&lt;ffffffff8150a2d2&gt;] system_call_fastpath+0x16/0x1b
 ---[ end trace 940358030751eafb ]---

The above mentioned commit didn't go far enough. Well, it covered the
function tracer by adding checks in __register_ftrace_function(). The
problem is that the function graph tracer circumvents that (for a slight
efficiency gain when function graph trace is running with a function
tracer. The gain was not worth this).

The problem came with ftrace_startup() which should always be called after
__register_ftrace_function(), if you want this bug to be completely fixed.

Anyway, this solution moves __register_ftrace_function() inside of
ftrace_startup() and removes the need to call them both.

Reported-by: Dave Wysochanski &lt;dwysocha@redhat.com&gt;
Fixes: ed926f9b35cd ("ftrace: Use counters to enable functions to trace")
Cc: stable@vger.kernel.org # 3.0+
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 8c4f3c3fa9681 "ftrace: Check module functions being traced on reload"
fixed module loading and unloading with respect to function tracing, but
it missed the function graph tracer. If you perform the following

 # cd /sys/kernel/debug/tracing
 # echo function_graph &gt; current_tracer
 # modprobe nfsd
 # echo nop &gt; current_tracer

You'll get the following oops message:

 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 2910 at /linux.git/kernel/trace/ftrace.c:1640 __ftrace_hash_rec_update.part.35+0x168/0x1b9()
 Modules linked in: nfsd exportfs nfs_acl lockd ipt_MASQUERADE sunrpc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables uinput snd_hda_codec_idt
 CPU: 2 PID: 2910 Comm: bash Not tainted 3.13.0-rc1-test #7
 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007
  0000000000000668 ffff8800787efcf8 ffffffff814fe193 ffff88007d500000
  0000000000000000 ffff8800787efd38 ffffffff8103b80a 0000000000000668
  ffffffff810b2b9a ffffffff81a48370 0000000000000001 ffff880037aea000
 Call Trace:
  [&lt;ffffffff814fe193&gt;] dump_stack+0x4f/0x7c
  [&lt;ffffffff8103b80a&gt;] warn_slowpath_common+0x81/0x9b
  [&lt;ffffffff810b2b9a&gt;] ? __ftrace_hash_rec_update.part.35+0x168/0x1b9
  [&lt;ffffffff8103b83e&gt;] warn_slowpath_null+0x1a/0x1c
  [&lt;ffffffff810b2b9a&gt;] __ftrace_hash_rec_update.part.35+0x168/0x1b9
  [&lt;ffffffff81502f89&gt;] ? __mutex_lock_slowpath+0x364/0x364
  [&lt;ffffffff810b2cc2&gt;] ftrace_shutdown+0xd7/0x12b
  [&lt;ffffffff810b47f0&gt;] unregister_ftrace_graph+0x49/0x78
  [&lt;ffffffff810c4b30&gt;] graph_trace_reset+0xe/0x10
  [&lt;ffffffff810bf393&gt;] tracing_set_tracer+0xa7/0x26a
  [&lt;ffffffff810bf5e1&gt;] tracing_set_trace_write+0x8b/0xbd
  [&lt;ffffffff810c501c&gt;] ? ftrace_return_to_handler+0xb2/0xde
  [&lt;ffffffff811240a8&gt;] ? __sb_end_write+0x5e/0x5e
  [&lt;ffffffff81122aed&gt;] vfs_write+0xab/0xf6
  [&lt;ffffffff8150a185&gt;] ftrace_graph_caller+0x85/0x85
  [&lt;ffffffff81122dbd&gt;] SyS_write+0x59/0x82
  [&lt;ffffffff8150a185&gt;] ftrace_graph_caller+0x85/0x85
  [&lt;ffffffff8150a2d2&gt;] system_call_fastpath+0x16/0x1b
 ---[ end trace 940358030751eafb ]---

The above mentioned commit didn't go far enough. Well, it covered the
function tracer by adding checks in __register_ftrace_function(). The
problem is that the function graph tracer circumvents that (for a slight
efficiency gain when function graph trace is running with a function
tracer. The gain was not worth this).

The problem came with ftrace_startup() which should always be called after
__register_ftrace_function(), if you want this bug to be completely fixed.

Anyway, this solution moves __register_ftrace_function() inside of
ftrace_startup() and removes the need to call them both.

Reported-by: Dave Wysochanski &lt;dwysocha@redhat.com&gt;
Fixes: ed926f9b35cd ("ftrace: Use counters to enable functions to trace")
Cc: stable@vger.kernel.org # 3.0+
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6</title>
<updated>2013-11-24T00:18:25+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-11-24T00:18:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=26b265cd29dde56bf0901c421eabc7ae815f38c4'/>
<id>26b265cd29dde56bf0901c421eabc7ae815f38c4</id>
<content type='text'>
Pull crypto update from Herbert Xu:
 - Made x86 ablk_helper generic for ARM
 - Phase out chainiv in favour of eseqiv (affects IPsec)
 - Fixed aes-cbc IV corruption on s390
 - Added constant-time crypto_memneq which replaces memcmp
 - Fixed aes-ctr in omap-aes
 - Added OMAP3 ROM RNG support
 - Add PRNG support for MSM SoC's
 - Add and use Job Ring API in caam
 - Misc fixes

[ NOTE! This pull request was sent within the merge window, but Herbert
  has some questionable email sending setup that makes him public enemy
  #1 as far as gmail is concerned.  So most of his emails seem to be
  trapped by gmail as spam, resulting in me not seeing them.  - Linus ]

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (49 commits)
  crypto: s390 - Fix aes-cbc IV corruption
  crypto: omap-aes - Fix CTR mode counter length
  crypto: omap-sham - Add missing modalias
  padata: make the sequence counter an atomic_t
  crypto: caam - Modify the interface layers to use JR API's
  crypto: caam - Add API's to allocate/free Job Rings
  crypto: caam - Add Platform driver for Job Ring
  hwrng: msm - Add PRNG support for MSM SoC's
  ARM: DT: msm: Add Qualcomm's PRNG driver binding document
  crypto: skcipher - Use eseqiv even on UP machines
  crypto: talitos - Simplify key parsing
  crypto: picoxcell - Simplify and harden key parsing
  crypto: ixp4xx - Simplify and harden key parsing
  crypto: authencesn - Simplify key parsing
  crypto: authenc - Export key parsing helper function
  crypto: mv_cesa: remove deprecated IRQF_DISABLED
  hwrng: OMAP3 ROM Random Number Generator support
  crypto: sha256_ssse3 - also test for BMI2
  crypto: mv_cesa - Remove redundant of_match_ptr
  crypto: sahara - Remove redundant of_match_ptr
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull crypto update from Herbert Xu:
 - Made x86 ablk_helper generic for ARM
 - Phase out chainiv in favour of eseqiv (affects IPsec)
 - Fixed aes-cbc IV corruption on s390
 - Added constant-time crypto_memneq which replaces memcmp
 - Fixed aes-ctr in omap-aes
 - Added OMAP3 ROM RNG support
 - Add PRNG support for MSM SoC's
 - Add and use Job Ring API in caam
 - Misc fixes

[ NOTE! This pull request was sent within the merge window, but Herbert
  has some questionable email sending setup that makes him public enemy
  #1 as far as gmail is concerned.  So most of his emails seem to be
  trapped by gmail as spam, resulting in me not seeing them.  - Linus ]

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (49 commits)
  crypto: s390 - Fix aes-cbc IV corruption
  crypto: omap-aes - Fix CTR mode counter length
  crypto: omap-sham - Add missing modalias
  padata: make the sequence counter an atomic_t
  crypto: caam - Modify the interface layers to use JR API's
  crypto: caam - Add API's to allocate/free Job Rings
  crypto: caam - Add Platform driver for Job Ring
  hwrng: msm - Add PRNG support for MSM SoC's
  ARM: DT: msm: Add Qualcomm's PRNG driver binding document
  crypto: skcipher - Use eseqiv even on UP machines
  crypto: talitos - Simplify key parsing
  crypto: picoxcell - Simplify and harden key parsing
  crypto: ixp4xx - Simplify and harden key parsing
  crypto: authencesn - Simplify key parsing
  crypto: authenc - Export key parsing helper function
  crypto: mv_cesa: remove deprecated IRQF_DISABLED
  hwrng: OMAP3 ROM Random Number Generator support
  crypto: sha256_ssse3 - also test for BMI2
  crypto: mv_cesa - Remove redundant of_match_ptr
  crypto: sahara - Remove redundant of_match_ptr
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>workqueue: fix pool ID allocation leakage and remove BUILD_BUG_ON() in init_workqueues</title>
<updated>2013-11-22T23:14:47+00:00</updated>
<author>
<name>Li Bin</name>
<email>huawei.libin@huawei.com</email>
</author>
<published>2013-09-10T01:52:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4e8b22bd1a37447712f1b1d96352fc53b463c6b3'/>
<id>4e8b22bd1a37447712f1b1d96352fc53b463c6b3</id>
<content type='text'>
When one work starts execution, the high bits of work's data contain
pool ID. It can represent a maximum of WORK_OFFQ_POOL_NONE. Pool ID
is assigned WORK_OFFQ_POOL_NONE when the work being initialized
indicating that no pool is associated and get_work_pool() uses it to
check the associated pool. So if worker_pool_assign_id() assigns a
ID greater than or equal WORK_OFFQ_POOL_NONE to a pool, it triggers
leakage, and it may break the non-reentrance guarantee.

This patch fix this issue by modifying the worker_pool_assign_id()
function calling idr_alloc() by setting @end param WORK_OFFQ_POOL_NONE.

Furthermore, in the current implementation, the BUILD_BUG_ON() in
init_workqueues makes no sense. The number of worker pools needed
cannot be determined at compile time, because the number of backing
pools for UNBOUND workqueues is dynamic based on the assigned custom
attributes. So remove it.

tj: Minor comment and indentation updates.

Signed-off-by: Li Bin &lt;huawei.libin@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When one work starts execution, the high bits of work's data contain
pool ID. It can represent a maximum of WORK_OFFQ_POOL_NONE. Pool ID
is assigned WORK_OFFQ_POOL_NONE when the work being initialized
indicating that no pool is associated and get_work_pool() uses it to
check the associated pool. So if worker_pool_assign_id() assigns a
ID greater than or equal WORK_OFFQ_POOL_NONE to a pool, it triggers
leakage, and it may break the non-reentrance guarantee.

This patch fix this issue by modifying the worker_pool_assign_id()
function calling idr_alloc() by setting @end param WORK_OFFQ_POOL_NONE.

Furthermore, in the current implementation, the BUILD_BUG_ON() in
init_workqueues makes no sense. The number of worker pools needed
cannot be determined at compile time, because the number of backing
pools for UNBOUND workqueues is dynamic based on the assigned custom
attributes. So remove it.

tj: Minor comment and indentation updates.

Signed-off-by: Li Bin &lt;huawei.libin@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>workqueue: fix comment typo for __queue_work()</title>
<updated>2013-11-22T23:14:27+00:00</updated>
<author>
<name>Li Bin</name>
<email>huawei.libin@huawei.com</email>
</author>
<published>2013-09-09T05:13:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9ef28a73ff6a1598d6f915973c282fe28291f800'/>
<id>9ef28a73ff6a1598d6f915973c282fe28291f800</id>
<content type='text'>
It seems the "dying" should be "draining" here.

Signed-off-by: Li Bin &lt;huawei.libin@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It seems the "dying" should be "draining" here.

Signed-off-by: Li Bin &lt;huawei.libin@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
