<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/kernel, branch v4.19.103</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>perf/core: Fix mlock accounting in perf_mmap()</title>
<updated>2020-02-11T12:34:19+00:00</updated>
<author>
<name>Song Liu</name>
<email>songliubraving@fb.com</email>
</author>
<published>2020-01-23T18:11:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a3623db43a3c06538591370db955d85b80657e17'/>
<id>a3623db43a3c06538591370db955d85b80657e17</id>
<content type='text'>
commit 003461559ef7a9bd0239bae35a22ad8924d6e9ad upstream.

Decreasing sysctl_perf_event_mlock between two consecutive perf_mmap()s of
a perf ring buffer may lead to an integer underflow in locked memory
accounting. This may lead to the undesired behaviors, such as failures in
BPF map creation.

Address this by adjusting the accounting logic to take into account the
possibility that the amount of already locked memory may exceed the
current limit.

Fixes: c4b75479741c ("perf/core: Make the mlock accounting simple again")
Suggested-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Acked-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Link: https://lkml.kernel.org/r/20200123181146.2238074-1-songliubraving@fb.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 003461559ef7a9bd0239bae35a22ad8924d6e9ad upstream.

Decreasing sysctl_perf_event_mlock between two consecutive perf_mmap()s of
a perf ring buffer may lead to an integer underflow in locked memory
accounting. This may lead to the undesired behaviors, such as failures in
BPF map creation.

Address this by adjusting the accounting logic to take into account the
possibility that the amount of already locked memory may exceed the
current limit.

Fixes: c4b75479741c ("perf/core: Make the mlock accounting simple again")
Suggested-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Acked-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Link: https://lkml.kernel.org/r/20200123181146.2238074-1-songliubraving@fb.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>clocksource: Prevent double add_timer_on() for watchdog_timer</title>
<updated>2020-02-11T12:34:18+00:00</updated>
<author>
<name>Konstantin Khlebnikov</name>
<email>khlebnikov@yandex-team.ru</email>
</author>
<published>2020-01-31T16:08:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6284d30e96ede11d9d434eebfacbe4b4625b6c87'/>
<id>6284d30e96ede11d9d434eebfacbe4b4625b6c87</id>
<content type='text'>
commit febac332a819f0e764aa4da62757ba21d18c182b upstream.

Kernel crashes inside QEMU/KVM are observed:

  kernel BUG at kernel/time/timer.c:1154!
  BUG_ON(timer_pending(timer) || !timer-&gt;function) in add_timer_on().

At the same time another cpu got:

  general protection fault: 0000 [#1] SMP PTI of poinson pointer 0xdead000000000200 in:

  __hlist_del at include/linux/list.h:681
  (inlined by) detach_timer at kernel/time/timer.c:818
  (inlined by) expire_timers at kernel/time/timer.c:1355
  (inlined by) __run_timers at kernel/time/timer.c:1686
  (inlined by) run_timer_softirq at kernel/time/timer.c:1699

Unfortunately kernel logs are badly scrambled, stacktraces are lost.

Printing the timer-&gt;function before the BUG_ON() pointed to
clocksource_watchdog().

The execution of clocksource_watchdog() can race with a sequence of
clocksource_stop_watchdog() .. clocksource_start_watchdog():

expire_timers()
 detach_timer(timer, true);
  timer-&gt;entry.pprev = NULL;
 raw_spin_unlock_irq(&amp;base-&gt;lock);
 call_timer_fn
  clocksource_watchdog()

					clocksource_watchdog_kthread() or
					clocksource_unbind()

					spin_lock_irqsave(&amp;watchdog_lock, flags);
					clocksource_stop_watchdog();
					 del_timer(&amp;watchdog_timer);
					 watchdog_running = 0;
					spin_unlock_irqrestore(&amp;watchdog_lock, flags);

					spin_lock_irqsave(&amp;watchdog_lock, flags);
					clocksource_start_watchdog();
					 add_timer_on(&amp;watchdog_timer, ...);
					 watchdog_running = 1;
					spin_unlock_irqrestore(&amp;watchdog_lock, flags);

  spin_lock(&amp;watchdog_lock);
  add_timer_on(&amp;watchdog_timer, ...);
   BUG_ON(timer_pending(timer) || !timer-&gt;function);
    timer_pending() -&gt; true
    BUG()

I.e. inside clocksource_watchdog() watchdog_timer could be already armed.

Check timer_pending() before calling add_timer_on(). This is sufficient as
all operations are synchronized by watchdog_lock.

Fixes: 75c5158f70c0 ("timekeeping: Update clocksource with stop_machine")
Signed-off-by: Konstantin Khlebnikov &lt;khlebnikov@yandex-team.ru&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/158048693917.4378.13823603769948933793.stgit@buzz
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit febac332a819f0e764aa4da62757ba21d18c182b upstream.

Kernel crashes inside QEMU/KVM are observed:

  kernel BUG at kernel/time/timer.c:1154!
  BUG_ON(timer_pending(timer) || !timer-&gt;function) in add_timer_on().

At the same time another cpu got:

  general protection fault: 0000 [#1] SMP PTI of poinson pointer 0xdead000000000200 in:

  __hlist_del at include/linux/list.h:681
  (inlined by) detach_timer at kernel/time/timer.c:818
  (inlined by) expire_timers at kernel/time/timer.c:1355
  (inlined by) __run_timers at kernel/time/timer.c:1686
  (inlined by) run_timer_softirq at kernel/time/timer.c:1699

Unfortunately kernel logs are badly scrambled, stacktraces are lost.

Printing the timer-&gt;function before the BUG_ON() pointed to
clocksource_watchdog().

The execution of clocksource_watchdog() can race with a sequence of
clocksource_stop_watchdog() .. clocksource_start_watchdog():

expire_timers()
 detach_timer(timer, true);
  timer-&gt;entry.pprev = NULL;
 raw_spin_unlock_irq(&amp;base-&gt;lock);
 call_timer_fn
  clocksource_watchdog()

					clocksource_watchdog_kthread() or
					clocksource_unbind()

					spin_lock_irqsave(&amp;watchdog_lock, flags);
					clocksource_stop_watchdog();
					 del_timer(&amp;watchdog_timer);
					 watchdog_running = 0;
					spin_unlock_irqrestore(&amp;watchdog_lock, flags);

					spin_lock_irqsave(&amp;watchdog_lock, flags);
					clocksource_start_watchdog();
					 add_timer_on(&amp;watchdog_timer, ...);
					 watchdog_running = 1;
					spin_unlock_irqrestore(&amp;watchdog_lock, flags);

  spin_lock(&amp;watchdog_lock);
  add_timer_on(&amp;watchdog_timer, ...);
   BUG_ON(timer_pending(timer) || !timer-&gt;function);
    timer_pending() -&gt; true
    BUG()

I.e. inside clocksource_watchdog() watchdog_timer could be already armed.

Check timer_pending() before calling add_timer_on(). This is sufficient as
all operations are synchronized by watchdog_lock.

Fixes: 75c5158f70c0 ("timekeeping: Update clocksource with stop_machine")
Signed-off-by: Konstantin Khlebnikov &lt;khlebnikov@yandex-team.ru&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/158048693917.4378.13823603769948933793.stgit@buzz
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86/apic/msi: Plug non-maskable MSI affinity race</title>
<updated>2020-02-11T12:34:18+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2020-01-31T14:26:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=032a2bf9787acdaef31369045ff0cb0b301eee61'/>
<id>032a2bf9787acdaef31369045ff0cb0b301eee61</id>
<content type='text'>
commit 6f1a4891a5928a5969c87fa5a584844c983ec823 upstream.

Evan tracked down a subtle race between the update of the MSI message and
the device raising an interrupt internally on PCI devices which do not
support MSI masking. The update of the MSI message is non-atomic and
consists of either 2 or 3 sequential 32bit wide writes to the PCI config
space.

   - Write address low 32bits
   - Write address high 32bits (If supported by device)
   - Write data

When an interrupt is migrated then both address and data might change, so
the kernel attempts to mask the MSI interrupt first. But for MSI masking is
optional, so there exist devices which do not provide it. That means that
if the device raises an interrupt internally between the writes then a MSI
message is sent built from half updated state.

On x86 this can lead to spurious interrupts on the wrong interrupt
vector when the affinity setting changes both address and data. As a
consequence the device interrupt can be lost causing the device to
become stuck or malfunctioning.

Evan tried to handle that by disabling MSI accross an MSI message
update. That's not feasible because disabling MSI has issues on its own:

 If MSI is disabled the PCI device is routing an interrupt to the legacy
 INTx mechanism. The INTx delivery can be disabled, but the disablement is
 not working on all devices.

 Some devices lose interrupts when both MSI and INTx delivery are disabled.

Another way to solve this would be to enforce the allocation of the same
vector on all CPUs in the system for this kind of screwed devices. That
could be done, but it would bring back the vector space exhaustion problems
which got solved a few years ago.

Fortunately the high address (if supported by the device) is only relevant
when X2APIC is enabled which implies interrupt remapping. In the interrupt
remapping case the affinity setting is happening at the interrupt remapping
unit and the PCI MSI message is programmed only once when the PCI device is
initialized.

That makes it possible to solve it with a two step update:

  1) Target the MSI msg to the new vector on the current target CPU

  2) Target the MSI msg to the new vector on the new target CPU

In both cases writing the MSI message is only changing a single 32bit word
which prevents the issue of inconsistency.

After writing the final destination it is necessary to check whether the
device issued an interrupt while the intermediate state #1 (new vector,
current CPU) was in effect.

This is possible because the affinity change is always happening on the
current target CPU. The code runs with interrupts disabled, so the
interrupt can be detected by checking the IRR of the local APIC. If the
vector is pending in the IRR then the interrupt is retriggered on the new
target CPU by sending an IPI for the associated vector on the target CPU.

This can cause spurious interrupts on both the local and the new target
CPU.

 1) If the new vector is not in use on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then interrupt entry code will
    ignore that spurious interrupt. The vector is marked so that the
    'No irq handler for vector' warning is supressed once.

 2) If the new vector is in use already on the local CPU then the IRR check
    might see an pending interrupt from the device which is using this
    vector. The IPI to the new target CPU will then invoke the handler of
    the device, which got the affinity change, even if that device did not
    issue an interrupt

 3) If the new vector is in use already on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then the handler of the device which
    uses that vector on the local CPU will be invoked.

expose issues in device driver interrupt handlers which are not prepared to
handle a spurious interrupt correctly. This not a regression, it's just
exposing something which was already broken as spurious interrupts can
happen for a lot of reasons and all driver handlers need to be able to deal
with them.

Reported-by: Evan Green &lt;evgreen@chromium.org&gt;
Debugged-by: Evan Green &lt;evgreen@chromium.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Tested-by: Evan Green &lt;evgreen@chromium.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87imkr4s7n.fsf@nanos.tec.linutronix.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6f1a4891a5928a5969c87fa5a584844c983ec823 upstream.

Evan tracked down a subtle race between the update of the MSI message and
the device raising an interrupt internally on PCI devices which do not
support MSI masking. The update of the MSI message is non-atomic and
consists of either 2 or 3 sequential 32bit wide writes to the PCI config
space.

   - Write address low 32bits
   - Write address high 32bits (If supported by device)
   - Write data

When an interrupt is migrated then both address and data might change, so
the kernel attempts to mask the MSI interrupt first. But for MSI masking is
optional, so there exist devices which do not provide it. That means that
if the device raises an interrupt internally between the writes then a MSI
message is sent built from half updated state.

On x86 this can lead to spurious interrupts on the wrong interrupt
vector when the affinity setting changes both address and data. As a
consequence the device interrupt can be lost causing the device to
become stuck or malfunctioning.

Evan tried to handle that by disabling MSI accross an MSI message
update. That's not feasible because disabling MSI has issues on its own:

 If MSI is disabled the PCI device is routing an interrupt to the legacy
 INTx mechanism. The INTx delivery can be disabled, but the disablement is
 not working on all devices.

 Some devices lose interrupts when both MSI and INTx delivery are disabled.

Another way to solve this would be to enforce the allocation of the same
vector on all CPUs in the system for this kind of screwed devices. That
could be done, but it would bring back the vector space exhaustion problems
which got solved a few years ago.

Fortunately the high address (if supported by the device) is only relevant
when X2APIC is enabled which implies interrupt remapping. In the interrupt
remapping case the affinity setting is happening at the interrupt remapping
unit and the PCI MSI message is programmed only once when the PCI device is
initialized.

That makes it possible to solve it with a two step update:

  1) Target the MSI msg to the new vector on the current target CPU

  2) Target the MSI msg to the new vector on the new target CPU

In both cases writing the MSI message is only changing a single 32bit word
which prevents the issue of inconsistency.

After writing the final destination it is necessary to check whether the
device issued an interrupt while the intermediate state #1 (new vector,
current CPU) was in effect.

This is possible because the affinity change is always happening on the
current target CPU. The code runs with interrupts disabled, so the
interrupt can be detected by checking the IRR of the local APIC. If the
vector is pending in the IRR then the interrupt is retriggered on the new
target CPU by sending an IPI for the associated vector on the target CPU.

This can cause spurious interrupts on both the local and the new target
CPU.

 1) If the new vector is not in use on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then interrupt entry code will
    ignore that spurious interrupt. The vector is marked so that the
    'No irq handler for vector' warning is supressed once.

 2) If the new vector is in use already on the local CPU then the IRR check
    might see an pending interrupt from the device which is using this
    vector. The IPI to the new target CPU will then invoke the handler of
    the device, which got the affinity change, even if that device did not
    issue an interrupt

 3) If the new vector is in use already on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then the handler of the device which
    uses that vector on the local CPU will be invoked.

expose issues in device driver interrupt handlers which are not prepared to
handle a spurious interrupt correctly. This not a regression, it's just
exposing something which was already broken as spurious interrupts can
happen for a lot of reasons and all driver handlers need to be able to deal
with them.

Reported-by: Evan Green &lt;evgreen@chromium.org&gt;
Debugged-by: Evan Green &lt;evgreen@chromium.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Tested-by: Evan Green &lt;evgreen@chromium.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87imkr4s7n.fsf@nanos.tec.linutronix.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ftrace: Protect ftrace_graph_hash with ftrace_sync</title>
<updated>2020-02-11T12:34:05+00:00</updated>
<author>
<name>Steven Rostedt (VMware)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2020-02-05T14:20:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0948d6294d7bb1957125b01adc2e8df75da52b98'/>
<id>0948d6294d7bb1957125b01adc2e8df75da52b98</id>
<content type='text'>
[ Upstream commit 54a16ff6f2e50775145b210bcd94d62c3c2af117 ]

As function_graph tracer can run when RCU is not "watching", it can not be
protected by synchronize_rcu() it requires running a task on each CPU before
it can be freed. Calling schedule_on_each_cpu(ftrace_sync) needs to be used.

Link: https://lore.kernel.org/r/20200205131110.GT2935@paulmck-ThinkPad-P72

Cc: stable@vger.kernel.org
Fixes: b9b0c831bed26 ("ftrace: Convert graph filter to use hash tables")
Reported-by: "Paul E. McKenney" &lt;paulmck@kernel.org&gt;
Reviewed-by: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 54a16ff6f2e50775145b210bcd94d62c3c2af117 ]

As function_graph tracer can run when RCU is not "watching", it can not be
protected by synchronize_rcu() it requires running a task on each CPU before
it can be freed. Calling schedule_on_each_cpu(ftrace_sync) needs to be used.

Link: https://lore.kernel.org/r/20200205131110.GT2935@paulmck-ThinkPad-P72

Cc: stable@vger.kernel.org
Fixes: b9b0c831bed26 ("ftrace: Convert graph filter to use hash tables")
Reported-by: "Paul E. McKenney" &lt;paulmck@kernel.org&gt;
Reviewed-by: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ftrace: Add comment to why rcu_dereference_sched() is open coded</title>
<updated>2020-02-11T12:34:04+00:00</updated>
<author>
<name>Steven Rostedt (VMware)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2020-02-05T07:17:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c03d23598062175c450a646763c2c0045a7aa35e'/>
<id>c03d23598062175c450a646763c2c0045a7aa35e</id>
<content type='text'>
[ Upstream commit 16052dd5bdfa16dbe18d8c1d4cde2ddab9d23177 ]

Because the function graph tracer can execute in sections where RCU is not
"watching", the rcu_dereference_sched() for the has needs to be open coded.
This is fine because the RCU "flavor" of the ftrace hash is protected by
its own RCU handling (it does its own little synchronization on every CPU
and does not rely on RCU sched).

Acked-by: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 16052dd5bdfa16dbe18d8c1d4cde2ddab9d23177 ]

Because the function graph tracer can execute in sections where RCU is not
"watching", the rcu_dereference_sched() for the has needs to be open coded.
This is fine because the RCU "flavor" of the ftrace hash is protected by
its own RCU handling (it does its own little synchronization on every CPU
and does not rely on RCU sched).

Acked-by: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing: Annotate ftrace_graph_notrace_hash pointer with __rcu</title>
<updated>2020-02-11T12:34:04+00:00</updated>
<author>
<name>Amol Grover</name>
<email>frextrite@gmail.com</email>
</author>
<published>2020-02-05T05:57:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=30afa80b0f6e03134d8e7d66a1111d066403ad3f'/>
<id>30afa80b0f6e03134d8e7d66a1111d066403ad3f</id>
<content type='text'>
[ Upstream commit fd0e6852c407dd9aefc594f54ddcc21d84803d3b ]

Fix following instances of sparse error
kernel/trace/ftrace.c:5667:29: error: incompatible types in comparison
kernel/trace/ftrace.c:5813:21: error: incompatible types in comparison
kernel/trace/ftrace.c:5868:36: error: incompatible types in comparison
kernel/trace/ftrace.c:5870:25: error: incompatible types in comparison

Use rcu_dereference_protected to dereference the newly annotated pointer.

Link: http://lkml.kernel.org/r/20200205055701.30195-1-frextrite@gmail.com

Signed-off-by: Amol Grover &lt;frextrite@gmail.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit fd0e6852c407dd9aefc594f54ddcc21d84803d3b ]

Fix following instances of sparse error
kernel/trace/ftrace.c:5667:29: error: incompatible types in comparison
kernel/trace/ftrace.c:5813:21: error: incompatible types in comparison
kernel/trace/ftrace.c:5868:36: error: incompatible types in comparison
kernel/trace/ftrace.c:5870:25: error: incompatible types in comparison

Use rcu_dereference_protected to dereference the newly annotated pointer.

Link: http://lkml.kernel.org/r/20200205055701.30195-1-frextrite@gmail.com

Signed-off-by: Amol Grover &lt;frextrite@gmail.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing: Annotate ftrace_graph_hash pointer with __rcu</title>
<updated>2020-02-11T12:34:04+00:00</updated>
<author>
<name>Amol Grover</name>
<email>frextrite@gmail.com</email>
</author>
<published>2020-02-01T07:27:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f144ad2e843435fed0c2945544594e223a9410cc'/>
<id>f144ad2e843435fed0c2945544594e223a9410cc</id>
<content type='text'>
[ Upstream commit 24a9729f831462b1d9d61dc85ecc91c59037243f ]

Fix following instances of sparse error
kernel/trace/ftrace.c:5664:29: error: incompatible types in comparison
kernel/trace/ftrace.c:5785:21: error: incompatible types in comparison
kernel/trace/ftrace.c:5864:36: error: incompatible types in comparison
kernel/trace/ftrace.c:5866:25: error: incompatible types in comparison

Use rcu_dereference_protected to access the __rcu annotated pointer.

Link: http://lkml.kernel.org/r/20200201072703.17330-1-frextrite@gmail.com

Reviewed-by: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Signed-off-by: Amol Grover &lt;frextrite@gmail.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 24a9729f831462b1d9d61dc85ecc91c59037243f ]

Fix following instances of sparse error
kernel/trace/ftrace.c:5664:29: error: incompatible types in comparison
kernel/trace/ftrace.c:5785:21: error: incompatible types in comparison
kernel/trace/ftrace.c:5864:36: error: incompatible types in comparison
kernel/trace/ftrace.c:5866:25: error: incompatible types in comparison

Use rcu_dereference_protected to access the __rcu annotated pointer.

Link: http://lkml.kernel.org/r/20200201072703.17330-1-frextrite@gmail.com

Reviewed-by: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Signed-off-by: Amol Grover &lt;frextrite@gmail.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>padata: Remove broken queue flushing</title>
<updated>2020-02-11T12:34:04+00:00</updated>
<author>
<name>Herbert Xu</name>
<email>herbert@gondor.apana.org.au</email>
</author>
<published>2019-11-19T05:17:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dc34710a7aba5207e7cb99d11588c04535b3c53d'/>
<id>dc34710a7aba5207e7cb99d11588c04535b3c53d</id>
<content type='text'>
[ Upstream commit 07928d9bfc81640bab36f5190e8725894d93b659 ]

The function padata_flush_queues is fundamentally broken because
it cannot force padata users to complete the request that is
underway.  IOW padata has to passively wait for the completion
of any outstanding work.

As it stands flushing is used in two places.  Its use in padata_stop
is simply unnecessary because nothing depends on the queues to
be flushed afterwards.

The other use in padata_replace is more substantial as we depend
on it to free the old pd structure.  This patch instead uses the
pd-&gt;refcnt to dynamically free the pd structure once all requests
are complete.

Fixes: 2b73b07ab8a4 ("padata: Flush the padata queues actively")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Reviewed-by: Daniel Jordan &lt;daniel.m.jordan@oracle.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 07928d9bfc81640bab36f5190e8725894d93b659 ]

The function padata_flush_queues is fundamentally broken because
it cannot force padata users to complete the request that is
underway.  IOW padata has to passively wait for the completion
of any outstanding work.

As it stands flushing is used in two places.  Its use in padata_stop
is simply unnecessary because nothing depends on the queues to
be flushed afterwards.

The other use in padata_replace is more substantial as we depend
on it to free the old pd structure.  This patch instead uses the
pd-&gt;refcnt to dynamically free the pd structure once all requests
are complete.

Fixes: 2b73b07ab8a4 ("padata: Flush the padata queues actively")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Reviewed-by: Daniel Jordan &lt;daniel.m.jordan@oracle.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>alarmtimer: Unregister wakeup source when module get fails</title>
<updated>2020-02-11T12:33:59+00:00</updated>
<author>
<name>Stephen Boyd</name>
<email>swboyd@chromium.org</email>
</author>
<published>2020-01-09T15:59:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b522ff023e2daf109de25c94695b400bd217b3aa'/>
<id>b522ff023e2daf109de25c94695b400bd217b3aa</id>
<content type='text'>
commit 6b6d188aae79a630957aefd88ff5c42af6553ee3 upstream.

The alarmtimer_rtc_add_device() function creates a wakeup source and then
tries to grab a module reference. If that fails the function returns early
with an error code, but fails to remove the wakeup source.

Cleanup this exit path so there is no dangling wakeup source, which is
named 'alarmtime' left allocated which will conflict with another RTC
device that may be registered later.

Fixes: 51218298a25e ("alarmtimer: Ensure RTC module is not unloaded")
Signed-off-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200109155910.907-2-swboyd@chromium.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

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<pre>
commit 6b6d188aae79a630957aefd88ff5c42af6553ee3 upstream.

The alarmtimer_rtc_add_device() function creates a wakeup source and then
tries to grab a module reference. If that fails the function returns early
with an error code, but fails to remove the wakeup source.

Cleanup this exit path so there is no dangling wakeup source, which is
named 'alarmtime' left allocated which will conflict with another RTC
device that may be registered later.

Fixes: 51218298a25e ("alarmtimer: Ensure RTC module is not unloaded")
Signed-off-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200109155910.907-2-swboyd@chromium.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>irqdomain: Fix a memory leak in irq_domain_push_irq()</title>
<updated>2020-02-11T12:33:57+00:00</updated>
<author>
<name>Kevin Hao</name>
<email>haokexin@gmail.com</email>
</author>
<published>2020-01-20T04:35:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4f7d834cece26b4544f2eb4e6f46e70ec3caf7b2'/>
<id>4f7d834cece26b4544f2eb4e6f46e70ec3caf7b2</id>
<content type='text'>
commit 0f394daef89b38d58c91118a2b08b8a1b316703b upstream.

Fix a memory leak reported by kmemleak:
unreferenced object 0xffff000bc6f50e80 (size 128):
  comm "kworker/23:2", pid 201, jiffies 4294894947 (age 942.132s)
  hex dump (first 32 bytes):
    00 00 00 00 41 00 00 00 86 c0 03 00 00 00 00 00  ....A...........
    00 a0 b2 c6 0b 00 ff ff 40 51 fd 10 00 80 ff ff  ........@Q......
  backtrace:
    [&lt;00000000e62d2240&gt;] kmem_cache_alloc_trace+0x1a4/0x320
    [&lt;00000000279143c9&gt;] irq_domain_push_irq+0x7c/0x188
    [&lt;00000000d9f4c154&gt;] thunderx_gpio_probe+0x3ac/0x438
    [&lt;00000000fd09ec22&gt;] pci_device_probe+0xe4/0x198
    [&lt;00000000d43eca75&gt;] really_probe+0xdc/0x320
    [&lt;00000000d3ebab09&gt;] driver_probe_device+0x5c/0xf0
    [&lt;000000005b3ecaa0&gt;] __device_attach_driver+0x88/0xc0
    [&lt;000000004e5915f5&gt;] bus_for_each_drv+0x7c/0xc8
    [&lt;0000000079d4db41&gt;] __device_attach+0xe4/0x140
    [&lt;00000000883bbda9&gt;] device_initial_probe+0x18/0x20
    [&lt;000000003be59ef6&gt;] bus_probe_device+0x98/0xa0
    [&lt;0000000039b03d3f&gt;] deferred_probe_work_func+0x74/0xa8
    [&lt;00000000870934ce&gt;] process_one_work+0x1c8/0x470
    [&lt;00000000e3cce570&gt;] worker_thread+0x1f8/0x428
    [&lt;000000005d64975e&gt;] kthread+0xfc/0x128
    [&lt;00000000f0eaa764&gt;] ret_from_fork+0x10/0x18

Fixes: 495c38d3001f ("irqdomain: Add irq_domain_{push,pop}_irq() functions")
Signed-off-by: Kevin Hao &lt;haokexin@gmail.com&gt;
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200120043547.22271-1-haokexin@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0f394daef89b38d58c91118a2b08b8a1b316703b upstream.

Fix a memory leak reported by kmemleak:
unreferenced object 0xffff000bc6f50e80 (size 128):
  comm "kworker/23:2", pid 201, jiffies 4294894947 (age 942.132s)
  hex dump (first 32 bytes):
    00 00 00 00 41 00 00 00 86 c0 03 00 00 00 00 00  ....A...........
    00 a0 b2 c6 0b 00 ff ff 40 51 fd 10 00 80 ff ff  ........@Q......
  backtrace:
    [&lt;00000000e62d2240&gt;] kmem_cache_alloc_trace+0x1a4/0x320
    [&lt;00000000279143c9&gt;] irq_domain_push_irq+0x7c/0x188
    [&lt;00000000d9f4c154&gt;] thunderx_gpio_probe+0x3ac/0x438
    [&lt;00000000fd09ec22&gt;] pci_device_probe+0xe4/0x198
    [&lt;00000000d43eca75&gt;] really_probe+0xdc/0x320
    [&lt;00000000d3ebab09&gt;] driver_probe_device+0x5c/0xf0
    [&lt;000000005b3ecaa0&gt;] __device_attach_driver+0x88/0xc0
    [&lt;000000004e5915f5&gt;] bus_for_each_drv+0x7c/0xc8
    [&lt;0000000079d4db41&gt;] __device_attach+0xe4/0x140
    [&lt;00000000883bbda9&gt;] device_initial_probe+0x18/0x20
    [&lt;000000003be59ef6&gt;] bus_probe_device+0x98/0xa0
    [&lt;0000000039b03d3f&gt;] deferred_probe_work_func+0x74/0xa8
    [&lt;00000000870934ce&gt;] process_one_work+0x1c8/0x470
    [&lt;00000000e3cce570&gt;] worker_thread+0x1f8/0x428
    [&lt;000000005d64975e&gt;] kthread+0xfc/0x128
    [&lt;00000000f0eaa764&gt;] ret_from_fork+0x10/0x18

Fixes: 495c38d3001f ("irqdomain: Add irq_domain_{push,pop}_irq() functions")
Signed-off-by: Kevin Hao &lt;haokexin@gmail.com&gt;
Signed-off-by: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200120043547.22271-1-haokexin@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
