<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/kernel, branch v3.14-rc8</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>futex: revert back to the explicit waiter counting code</title>
<updated>2014-03-21T05:11:17+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-03-21T05:11:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=11d4616bd07f38d496bd489ed8fad1dc4d928823'/>
<id>11d4616bd07f38d496bd489ed8fad1dc4d928823</id>
<content type='text'>
Srikar Dronamraju reports that commit b0c29f79ecea ("futexes: Avoid
taking the hb-&gt;lock if there's nothing to wake up") causes java threads
getting stuck on futexes when runing specjbb on a power7 numa box.

The cause appears to be that the powerpc spinlocks aren't using the same
ticket lock model that we use on x86 (and other) architectures, which in
turn result in the "spin_is_locked()" test in hb_waiters_pending()
occasionally reporting an unlocked spinlock even when there are pending
waiters.

So this reinstates Davidlohr Bueso's original explicit waiter counting
code, which I had convinced Davidlohr to drop in favor of figuring out
the pending waiters by just using the existing state of the spinlock and
the wait queue.

Reported-and-tested-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Original-code-by: Davidlohr Bueso &lt;davidlohr@hp.com&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>
Srikar Dronamraju reports that commit b0c29f79ecea ("futexes: Avoid
taking the hb-&gt;lock if there's nothing to wake up") causes java threads
getting stuck on futexes when runing specjbb on a power7 numa box.

The cause appears to be that the powerpc spinlocks aren't using the same
ticket lock model that we use on x86 (and other) architectures, which in
turn result in the "spin_is_locked()" test in hb_waiters_pending()
occasionally reporting an unlocked spinlock even when there are pending
waiters.

So this reinstates Davidlohr Bueso's original explicit waiter counting
code, which I had convinced Davidlohr to drop in favor of figuring out
the pending waiters by just using the existing state of the spinlock and
the wait queue.

Reported-and-tested-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Original-code-by: Davidlohr Bueso &lt;davidlohr@hp.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'trace-fixes-v3.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2014-03-21T05:09:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-03-21T05:09:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=477cc48484ea0bfdee9e8319259b35a0ec03f332'/>
<id>477cc48484ea0bfdee9e8319259b35a0ec03f332</id>
<content type='text'>
Pull trace fix from Steven Rostedt:
 "Vaibhav Nagarnaik discovered that since 3.10 a clean-up patch made the
  array index in the trace event format bogus.

  He supplied an elegant solution that uses __stringify() and also
  removes the need for the event_storage and event_storage_mutex and
  also cuts off a few K of overhead from the trace events"

* tag 'trace-fixes-v3.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix array size mismatch in format string
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull trace fix from Steven Rostedt:
 "Vaibhav Nagarnaik discovered that since 3.10 a clean-up patch made the
  array index in the trace event format bogus.

  He supplied an elegant solution that uses __stringify() and also
  removes the need for the event_storage and event_storage_mutex and
  also cuts off a few K of overhead from the trace events"

* tag 'trace-fixes-v3.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix array size mismatch in format string
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing: Fix array size mismatch in format string</title>
<updated>2014-03-20T17:21:05+00:00</updated>
<author>
<name>Vaibhav Nagarnaik</name>
<email>vnagarnaik@google.com</email>
</author>
<published>2014-02-14T03:51:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=87291347c49dc40aa339f587b209618201c2e527'/>
<id>87291347c49dc40aa339f587b209618201c2e527</id>
<content type='text'>
In event format strings, the array size is reported in two locations.
One in array subscript and then via the "size:" attribute. The values
reported there have a mismatch.

For e.g., in sched:sched_switch the prev_comm and next_comm character
arrays have subscript values as [32] where as the actual field size is
16.

name: sched_switch
ID: 301
format:
        field:unsigned short common_type;       offset:0;       size:2; signed:0;
        field:unsigned char common_flags;       offset:2;       size:1; signed:0;
        field:unsigned char common_preempt_count;       offset:3;       size:1;signed:0;
        field:int common_pid;   offset:4;       size:4; signed:1;

        field:char prev_comm[32];       offset:8;       size:16;        signed:1;
        field:pid_t prev_pid;   offset:24;      size:4; signed:1;
        field:int prev_prio;    offset:28;      size:4; signed:1;
        field:long prev_state;  offset:32;      size:8; signed:1;
        field:char next_comm[32];       offset:40;      size:16;        signed:1;
        field:pid_t next_pid;   offset:56;      size:4; signed:1;
        field:int next_prio;    offset:60;      size:4; signed:1;

After bisection, the following commit was blamed:
92edca0 tracing: Use direct field, type and system names

This commit removes the duplication of strings for field-&gt;name and
field-&gt;type assuming that all the strings passed in
__trace_define_field() are immutable. This is not true for arrays, where
the type string is created in event_storage variable and field-&gt;type for
all array fields points to event_storage.

Use __stringify() to create a string constant for the type string.

Also, get rid of event_storage and event_storage_mutex that are not
needed anymore.

also, an added benefit is that this reduces the overhead of events a bit more:

   text    data     bss     dec     hex filename
8424787 2036472 1302528 11763787         b3804b vmlinux
8420814 2036408 1302528 11759750         b37086 vmlinux.patched

Link: http://lkml.kernel.org/r/1392349908-29685-1-git-send-email-vnagarnaik@google.com

Cc: Laurent Chavey &lt;chavey@google.com&gt;
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Vaibhav Nagarnaik &lt;vnagarnaik@google.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In event format strings, the array size is reported in two locations.
One in array subscript and then via the "size:" attribute. The values
reported there have a mismatch.

For e.g., in sched:sched_switch the prev_comm and next_comm character
arrays have subscript values as [32] where as the actual field size is
16.

name: sched_switch
ID: 301
format:
        field:unsigned short common_type;       offset:0;       size:2; signed:0;
        field:unsigned char common_flags;       offset:2;       size:1; signed:0;
        field:unsigned char common_preempt_count;       offset:3;       size:1;signed:0;
        field:int common_pid;   offset:4;       size:4; signed:1;

        field:char prev_comm[32];       offset:8;       size:16;        signed:1;
        field:pid_t prev_pid;   offset:24;      size:4; signed:1;
        field:int prev_prio;    offset:28;      size:4; signed:1;
        field:long prev_state;  offset:32;      size:8; signed:1;
        field:char next_comm[32];       offset:40;      size:16;        signed:1;
        field:pid_t next_pid;   offset:56;      size:4; signed:1;
        field:int next_prio;    offset:60;      size:4; signed:1;

After bisection, the following commit was blamed:
92edca0 tracing: Use direct field, type and system names

This commit removes the duplication of strings for field-&gt;name and
field-&gt;type assuming that all the strings passed in
__trace_define_field() are immutable. This is not true for arrays, where
the type string is created in event_storage variable and field-&gt;type for
all array fields points to event_storage.

Use __stringify() to create a string constant for the type string.

Also, get rid of event_storage and event_storage_mutex that are not
needed anymore.

also, an added benefit is that this reduces the overhead of events a bit more:

   text    data     bss     dec     hex filename
8424787 2036472 1302528 11763787         b3804b vmlinux
8420814 2036408 1302528 11759750         b37086 vmlinux.patched

Link: http://lkml.kernel.org/r/1392349908-29685-1-git-send-email-vnagarnaik@google.com

Cc: Laurent Chavey &lt;chavey@google.com&gt;
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Vaibhav Nagarnaik &lt;vnagarnaik@google.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup</title>
<updated>2014-03-19T23:13:40+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-03-19T23:13:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7c3895383fea48dab2374b04a936de4717a85a81'/>
<id>7c3895383fea48dab2374b04a936de4717a85a81</id>
<content type='text'>
Pull cgroup fix from Tejun Heo:
 "One really late cgroup patch to fix error path in create_css().
  Hitting this bug would be pretty rare but still possible and it gets
  delayed we'd need to backport it through -stable anyway.  It only
  updates error path in create_css() and has low chance of new
  breakages"

* 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix a failure path in create_css()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull cgroup fix from Tejun Heo:
 "One really late cgroup patch to fix error path in create_css().
  Hitting this bug would be pretty rare but still possible and it gets
  delayed we'd need to backport it through -stable anyway.  It only
  updates error path in create_css() and has low chance of new
  breakages"

* 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix a failure path in create_css()
</pre>
</div>
</content>
</entry>
<entry>
<title>cgroup: fix a failure path in create_css()</title>
<updated>2014-03-18T21:15:36+00:00</updated>
<author>
<name>Li Zefan</name>
<email>lizefan@huawei.com</email>
</author>
<published>2014-03-18T09:02:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3eb59ec64fc7a3f4576da23f811b39331b830ba2'/>
<id>3eb59ec64fc7a3f4576da23f811b39331b830ba2</id>
<content type='text'>
If online_css() fails, we should remove cgroup files belonging
to css-&gt;ss.

Signed-off-by: Li Zefan &lt;lizefan@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>
If online_css() fails, we should remove cgroup files belonging
to css-&gt;ss.

Signed-off-by: Li Zefan &lt;lizefan@huawei.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-03-16T17:42:07+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-03-16T17:42:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=59bf6c3c6c1e8463234015ae7690f5cdd991dffe'/>
<id>59bf6c3c6c1e8463234015ae7690f5cdd991dffe</id>
<content type='text'>
Pull scheduler fixes from Ingo Molnar:
 "Three small fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/clock: Prevent tracing recursion in sched_clock_cpu()
  stop_machine: Fix^2 race between stop_two_cpus() and stop_cpus()
  sched/deadline: Deny unprivileged users to set/change SCHED_DEADLINE policy
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull scheduler fixes from Ingo Molnar:
 "Three small fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/clock: Prevent tracing recursion in sched_clock_cpu()
  stop_machine: Fix^2 race between stop_two_cpus() and stop_cpus()
  sched/deadline: Deny unprivileged users to set/change SCHED_DEADLINE policy
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace</title>
<updated>2014-03-11T17:17:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-03-11T17:17:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=adf961d7e8006d2cb16ceee07582b145b9ef69f7'/>
<id>adf961d7e8006d2cb16ceee07582b145b9ef69f7</id>
<content type='text'>
Pull audit namespace fixes from Eric Biederman:
 "Starting with 3.14-rc1 the audit code is faulty (think oopses and
  races) with respect to how it computes the network namespace of which
  socket to reply to, and I happened to notice by chance when reading
  through the code.

  My testing and the automated build bots don't find any problems with
  these fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  audit: Update kdoc for audit_send_reply and audit_list_rules_send
  audit: Send replies in the proper network namespace.
  audit: Use struct net not pid_t to remember the network namespce to reply in
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull audit namespace fixes from Eric Biederman:
 "Starting with 3.14-rc1 the audit code is faulty (think oopses and
  races) with respect to how it computes the network namespace of which
  socket to reply to, and I happened to notice by chance when reading
  through the code.

  My testing and the automated build bots don't find any problems with
  these fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  audit: Update kdoc for audit_send_reply and audit_list_rules_send
  audit: Send replies in the proper network namespace.
  audit: Use struct net not pid_t to remember the network namespce to reply in
</pre>
</div>
</content>
</entry>
<entry>
<title>sched/clock: Prevent tracing recursion in sched_clock_cpu()</title>
<updated>2014-03-11T10:33:48+00:00</updated>
<author>
<name>Fernando Luis Vazquez Cao</name>
<email>fernando@oss.ntt.co.jp</email>
</author>
<published>2014-03-06T05:25:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=96b3d28bf4b00f62fc8386ff5d487d1830793a3d'/>
<id>96b3d28bf4b00f62fc8386ff5d487d1830793a3d</id>
<content type='text'>
Prevent tracing of preempt_disable/enable() in sched_clock_cpu().
When CONFIG_DEBUG_PREEMPT is enabled, preempt_disable/enable() are
traced and this causes trace_clock() users (and probably others) to
go into an infinite recursion. Systems with a stable sched_clock()
are not affected.

This problem is similar to that fixed by upstream commit 95ef1e52922
("KVM guest: prevent tracing recursion with kvmclock").

Signed-off-by: Fernando Luis Vazquez Cao &lt;fernando@oss.ntt.co.jp&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/1394083528.4524.3.camel@nexus
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Prevent tracing of preempt_disable/enable() in sched_clock_cpu().
When CONFIG_DEBUG_PREEMPT is enabled, preempt_disable/enable() are
traced and this causes trace_clock() users (and probably others) to
go into an infinite recursion. Systems with a stable sched_clock()
are not affected.

This problem is similar to that fixed by upstream commit 95ef1e52922
("KVM guest: prevent tracing recursion with kvmclock").

Signed-off-by: Fernando Luis Vazquez Cao &lt;fernando@oss.ntt.co.jp&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/1394083528.4524.3.camel@nexus
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>stop_machine: Fix^2 race between stop_two_cpus() and stop_cpus()</title>
<updated>2014-03-11T10:33:47+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2014-02-28T12:39:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=177c53d943368fc97644ebc0a250dc8e2d124250'/>
<id>177c53d943368fc97644ebc0a250dc8e2d124250</id>
<content type='text'>
We must use smp_call_function_single(.wait=1) for the
irq_cpu_stop_queue_work() to ensure the queueing is actually done under
stop_cpus_lock. Without this we could have dropped the lock by the time
we do the queueing and get the race we tried to fix.

Fixes: 7053ea1a34fa ("stop_machine: Fix race between stop_two_cpus() and stop_cpus()")

Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Prarit Bhargava &lt;prarit@redhat.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20140228123905.GK3104@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We must use smp_call_function_single(.wait=1) for the
irq_cpu_stop_queue_work() to ensure the queueing is actually done under
stop_cpus_lock. Without this we could have dropped the lock by the time
we do the queueing and get the race we tried to fix.

Fixes: 7053ea1a34fa ("stop_machine: Fix race between stop_two_cpus() and stop_cpus()")

Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Prarit Bhargava &lt;prarit@redhat.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Christoph Hellwig &lt;hch@infradead.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/r/20140228123905.GK3104@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched/deadline: Deny unprivileged users to set/change SCHED_DEADLINE policy</title>
<updated>2014-03-11T10:33:46+00:00</updated>
<author>
<name>Juri Lelli</name>
<email>juri.lelli@gmail.com</email>
</author>
<published>2014-03-03T11:09:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d44753b843e093f9e1f2f14806fbe106fff74898'/>
<id>d44753b843e093f9e1f2f14806fbe106fff74898</id>
<content type='text'>
Deny the use of SCHED_DEADLINE policy to unprivileged users.
Even if root users can set the policy for normal users, we
don't want the latter to be able to change their parameters
(safest behavior).

Signed-off-by: Juri Lelli &lt;juri.lelli@gmail.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/1393844961-18097-1-git-send-email-juri.lelli@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Deny the use of SCHED_DEADLINE policy to unprivileged users.
Even if root users can set the policy for normal users, we
don't want the latter to be able to change their parameters
(safest behavior).

Signed-off-by: Juri Lelli &lt;juri.lelli@gmail.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/1393844961-18097-1-git-send-email-juri.lelli@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
