<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/include/linux, branch v3.12.64</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>bonding: Fix bonding crash</title>
<updated>2016-09-29T09:14:10+00:00</updated>
<author>
<name>Mahesh Bandewar</name>
<email>maheshb@google.com</email>
</author>
<published>2016-09-02T05:18:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=19e352cad241ecb7c5b2b3436c9ce64002d6ff26'/>
<id>19e352cad241ecb7c5b2b3436c9ce64002d6ff26</id>
<content type='text'>
[ Upstream commit 24b27fc4cdf9e10c5e79e5923b6b7c2c5c95096c ]

Following few steps will crash kernel -

  (a) Create bonding master
      &gt; modprobe bonding miimon=50
  (b) Create macvlan bridge on eth2
      &gt; ip link add link eth2 dev mvl0 address aa:0:0:0:0:01 \
	   type macvlan
  (c) Now try adding eth2 into the bond
      &gt; echo +eth2 &gt; /sys/class/net/bond0/bonding/slaves
      &lt;crash&gt;

Bonding does lots of things before checking if the device enslaved is
busy or not.

In this case when the notifier call-chain sends notifications, the
bond_netdev_event() assumes that the rx_handler /rx_handler_data is
registered while the bond_enslave() hasn't progressed far enough to
register rx_handler for the new slave.

This patch adds a rx_handler check that can be performed right at the
beginning of the enslave code to avoid getting into this situation.

Signed-off-by: Mahesh Bandewar &lt;maheshb@google.com&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 24b27fc4cdf9e10c5e79e5923b6b7c2c5c95096c ]

Following few steps will crash kernel -

  (a) Create bonding master
      &gt; modprobe bonding miimon=50
  (b) Create macvlan bridge on eth2
      &gt; ip link add link eth2 dev mvl0 address aa:0:0:0:0:01 \
	   type macvlan
  (c) Now try adding eth2 into the bond
      &gt; echo +eth2 &gt; /sys/class/net/bond0/bonding/slaves
      &lt;crash&gt;

Bonding does lots of things before checking if the device enslaved is
busy or not.

In this case when the notifier call-chain sends notifications, the
bond_netdev_event() assumes that the rx_handler /rx_handler_data is
registered while the bond_enslave() hasn't progressed far enough to
register rx_handler for the new slave.

This patch adds a rx_handler check that can be performed right at the
beginning of the enslave code to avoid getting into this situation.

Signed-off-by: Mahesh Bandewar &lt;maheshb@google.com&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Input: i8042 - break load dependency between atkbd/psmouse and i8042</title>
<updated>2016-09-21T11:40:10+00:00</updated>
<author>
<name>Dmitry Torokhov</name>
<email>dmitry.torokhov@gmail.com</email>
</author>
<published>2016-07-25T18:36:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e5d9fc669fe391ba7bd187873051fec42d7fc7df'/>
<id>e5d9fc669fe391ba7bd187873051fec42d7fc7df</id>
<content type='text'>
commit 4097461897df91041382ff6fcd2bfa7ee6b2448c upstream.

As explained in 1407814240-4275-1-git-send-email-decui@microsoft.com we
have a hard load dependency between i8042 and atkbd which prevents
keyboard from working on Gen2 Hyper-V VMs.

&gt; hyperv_keyboard invokes serio_interrupt(), which needs a valid serio
&gt; driver like atkbd.c.  atkbd.c depends on libps2.c because it invokes
&gt; ps2_command().  libps2.c depends on i8042.c because it invokes
&gt; i8042_check_port_owner().  As a result, hyperv_keyboard actually
&gt; depends on i8042.c.
&gt;
&gt; For a Generation 2 Hyper-V VM (meaning no i8042 device emulated), if a
&gt; Linux VM (like Arch Linux) happens to configure CONFIG_SERIO_I8042=m
&gt; rather than =y, atkbd.ko can't load because i8042.ko can't load(due to
&gt; no i8042 device emulated) and finally hyperv_keyboard can't work and
&gt; the user can't input: https://bugs.archlinux.org/task/39820
&gt; (Ubuntu/RHEL/SUSE aren't affected since they use CONFIG_SERIO_I8042=y)

To break the dependency we move away from using i8042_check_port_owner()
and instead allow serio port owner specify a mutex that clients should use
to serialize PS/2 command stream.

Reported-by: Mark Laws &lt;mdl@60hz.org&gt;
Tested-by: Mark Laws &lt;mdl@60hz.org&gt;
Signed-off-by: Dmitry Torokhov &lt;dmitry.torokhov@gmail.com&gt;
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 4097461897df91041382ff6fcd2bfa7ee6b2448c upstream.

As explained in 1407814240-4275-1-git-send-email-decui@microsoft.com we
have a hard load dependency between i8042 and atkbd which prevents
keyboard from working on Gen2 Hyper-V VMs.

&gt; hyperv_keyboard invokes serio_interrupt(), which needs a valid serio
&gt; driver like atkbd.c.  atkbd.c depends on libps2.c because it invokes
&gt; ps2_command().  libps2.c depends on i8042.c because it invokes
&gt; i8042_check_port_owner().  As a result, hyperv_keyboard actually
&gt; depends on i8042.c.
&gt;
&gt; For a Generation 2 Hyper-V VM (meaning no i8042 device emulated), if a
&gt; Linux VM (like Arch Linux) happens to configure CONFIG_SERIO_I8042=m
&gt; rather than =y, atkbd.ko can't load because i8042.ko can't load(due to
&gt; no i8042 device emulated) and finally hyperv_keyboard can't work and
&gt; the user can't input: https://bugs.archlinux.org/task/39820
&gt; (Ubuntu/RHEL/SUSE aren't affected since they use CONFIG_SERIO_I8042=y)

To break the dependency we move away from using i8042_check_port_owner()
and instead allow serio port owner specify a mutex that clients should use
to serialize PS/2 command stream.

Reported-by: Mark Laws &lt;mdl@60hz.org&gt;
Tested-by: Mark Laws &lt;mdl@60hz.org&gt;
Signed-off-by: Dmitry Torokhov &lt;dmitry.torokhov@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Add Netronome NFP4000 PF device ID</title>
<updated>2016-09-21T11:40:08+00:00</updated>
<author>
<name>Simon Horman</name>
<email>simon.horman@netronome.com</email>
</author>
<published>2015-12-11T02:30:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b15280aa98e3faeb780a03ecbee8f77ac3e96080'/>
<id>b15280aa98e3faeb780a03ecbee8f77ac3e96080</id>
<content type='text'>
commit 69874ec233871a62e1bc8c89e643993af93a8630 upstream.

Add the device ID for the PF of the NFP4000.  The device ID for the VF,
0x6003, is already present as PCI_DEVICE_ID_NETRONOME_NFP6000_VF.

Signed-off-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 69874ec233871a62e1bc8c89e643993af93a8630 upstream.

Add the device ID for the PF of the NFP4000.  The device ID for the VF,
0x6003, is already present as PCI_DEVICE_ID_NETRONOME_NFP6000_VF.

Signed-off-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Add Netronome vendor and device IDs</title>
<updated>2016-09-21T11:40:07+00:00</updated>
<author>
<name>Jason S. McMullan</name>
<email>jason.mcmullan@netronome.com</email>
</author>
<published>2015-09-30T06:35:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=db5ba5779b1f8145576a2b59e6c71697a65286ac'/>
<id>db5ba5779b1f8145576a2b59e6c71697a65286ac</id>
<content type='text'>
commit a755e169031dac9ebaed03302c4921687c271d62 upstream.

Device IDs for the Netronome NFP3200, NFP3240, NFP6000, and NFP6000 SR-IOV
devices.

Signed-off-by: Jason S. McMullan &lt;jason.mcmullan@netronome.com&gt;
[simon: edited changelog]
Signed-off-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a755e169031dac9ebaed03302c4921687c271d62 upstream.

Device IDs for the Netronome NFP3200, NFP3240, NFP6000, and NFP6000 SR-IOV
devices.

Signed-off-by: Jason S. McMullan &lt;jason.mcmullan@netronome.com&gt;
[simon: edited changelog]
Signed-off-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>IB/mlx5: Fix post send fence logic</title>
<updated>2016-08-19T07:51:22+00:00</updated>
<author>
<name>Eli Cohen</name>
<email>eli@mellanox.com</email>
</author>
<published>2016-06-22T14:27:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=871ac53ff20207ce73ce23ee8afe1fe4bac7aaa0'/>
<id>871ac53ff20207ce73ce23ee8afe1fe4bac7aaa0</id>
<content type='text'>
commit c9b254955b9f8814966f5dabd34c39d0e0a2b437 upstream.

If the caller specified IB_SEND_FENCE in the send flags of the work
request and no previous work request stated that the successive one
should be fenced, the work request would be executed without a fence.
This could result in RDMA read or atomic operations failure due to a MR
being invalidated. Fix this by adding the mlx5 enumeration for fencing
RDMA/atomic operations and fix the logic to apply this.

Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters')
Signed-off-by: Eli Cohen &lt;eli@mellanox.com&gt;
Signed-off-by: Leon Romanovsky &lt;leon@kernel.org&gt;
Signed-off-by: Doug Ledford &lt;dledford@redhat.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c9b254955b9f8814966f5dabd34c39d0e0a2b437 upstream.

If the caller specified IB_SEND_FENCE in the send flags of the work
request and no previous work request stated that the successive one
should be fenced, the work request would be executed without a fence.
This could result in RDMA read or atomic operations failure due to a MR
being invalidated. Fix this by adding the mlx5 enumeration for fencing
RDMA/atomic operations and fix the logic to apply this.

Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters')
Signed-off-by: Eli Cohen &lt;eli@mellanox.com&gt;
Signed-off-by: Leon Romanovsky &lt;leon@kernel.org&gt;
Signed-off-by: Doug Ledford &lt;dledford@redhat.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>IB/mlx5: Fix MODIFY_QP command input structure</title>
<updated>2016-08-19T07:51:21+00:00</updated>
<author>
<name>Artemy Kovalyov</name>
<email>artemyko@mellanox.com</email>
</author>
<published>2016-06-17T12:33:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c70a6ed3121a631ed40cdce043551640b013690a'/>
<id>c70a6ed3121a631ed40cdce043551640b013690a</id>
<content type='text'>
commit e3353c268b06236d6c40fa1714c114f21f44451c upstream.

Make MODIFY_QP command input structure compliant to specification

Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters')
Signed-off-by: Artemy Kovalyov &lt;artemyko@mellanox.com&gt;
Signed-off-by: Leon Romanovsky &lt;leon@kernel.org&gt;
Signed-off-by: Doug Ledford &lt;dledford@redhat.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e3353c268b06236d6c40fa1714c114f21f44451c upstream.

Make MODIFY_QP command input structure compliant to specification

Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters')
Signed-off-by: Artemy Kovalyov &lt;artemyko@mellanox.com&gt;
Signed-off-by: Leon Romanovsky &lt;leon@kernel.org&gt;
Signed-off-by: Doug Ledford &lt;dledford@redhat.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>random32: add prandom_u32_max and convert open coded users</title>
<updated>2016-08-19T07:51:00+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>dborkman@redhat.com</email>
</author>
<published>2014-01-22T01:29:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=73596d54f314ac2cc24ab211bde7de10fbc2f2e7'/>
<id>73596d54f314ac2cc24ab211bde7de10fbc2f2e7</id>
<content type='text'>
commit f337db64af059c9a94278a8b0ab97d87259ff62f upstream.

Many functions have open coded a function that returns a random
number in range [0,N-1]. Under the assumption that we have a PRNG
such as taus113 with being well distributed in [0, ~0U] space,
we can implement such a function as uword t = (n*m')&gt;&gt;32, where
m' is a random number obtained from PRNG, n the right open interval
border and t our resulting random number, with n,m',t in u32 universe.

Lets go with Joe and simply call it prandom_u32_max(), although
technically we have an right open interval endpoint, but that we
have documented. Other users can further be migrated to the new
prandom_u32_max() function later on; for now, we need to make sure
to migrate reciprocal_divide() users for the reciprocal_divide()
follow-up fixup since their function signatures are going to change.

Joint work with Hannes Frederic Sowa.

Cc: Jakub Zawadzki &lt;darkjames-ws@darkjames.pl&gt;
Cc: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Hannes Frederic Sowa &lt;hannes@stressinduktion.org&gt;
Signed-off-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f337db64af059c9a94278a8b0ab97d87259ff62f upstream.

Many functions have open coded a function that returns a random
number in range [0,N-1]. Under the assumption that we have a PRNG
such as taus113 with being well distributed in [0, ~0U] space,
we can implement such a function as uword t = (n*m')&gt;&gt;32, where
m' is a random number obtained from PRNG, n the right open interval
border and t our resulting random number, with n,m',t in u32 universe.

Lets go with Joe and simply call it prandom_u32_max(), although
technically we have an right open interval endpoint, but that we
have documented. Other users can further be migrated to the new
prandom_u32_max() function later on; for now, we need to make sure
to migrate reciprocal_divide() users for the reciprocal_divide()
follow-up fixup since their function signatures are going to change.

Joint work with Hannes Frederic Sowa.

Cc: Jakub Zawadzki &lt;darkjames-ws@darkjames.pl&gt;
Cc: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Hannes Frederic Sowa &lt;hannes@stressinduktion.org&gt;
Signed-off-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: x_tables: speed up jump target validation</title>
<updated>2016-08-19T07:50:44+00:00</updated>
<author>
<name>Florian Westphal</name>
<email>fw@strlen.de</email>
</author>
<published>2016-07-14T15:51:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=26bb96ed3ac0386b54507e1bfcb9a90c534affbe'/>
<id>26bb96ed3ac0386b54507e1bfcb9a90c534affbe</id>
<content type='text'>
commit f4dc77713f8016d2e8a3295e1c9c53a21f296def upstream.

The dummy ruleset I used to test the original validation change was broken,
most rules were unreachable and were not tested by mark_source_chains().

In some cases rulesets that used to load in a few seconds now require
several minutes.

sample ruleset that shows the behaviour:

echo "*filter"
for i in $(seq 0 100000);do
        printf ":chain_%06x - [0:0]\n" $i
done
for i in $(seq 0 100000);do
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
done
echo COMMIT

[ pipe result into iptables-restore ]

This ruleset will be about 74mbyte in size, with ~500k searches
though all 500k[1] rule entries. iptables-restore will take forever
(gave up after 10 minutes)

Instead of always searching the entire blob for a match, fill an
array with the start offsets of every single ipt_entry struct,
then do a binary search to check if the jump target is present or not.

After this change ruleset restore times get again close to what one
gets when reverting 36472341017529e (~3 seconds on my workstation).

[1] every user-defined rule gets an implicit RETURN, so we get
300k jumps + 100k userchains + 100k returns -&gt; 500k rule entries

Fixes: 36472341017529e ("netfilter: x_tables: validate targets of jumps")
Reported-by: Jeff Wu &lt;wujiafu@gmail.com&gt;
Tested-by: Jeff Wu &lt;wujiafu@gmail.com&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f4dc77713f8016d2e8a3295e1c9c53a21f296def upstream.

The dummy ruleset I used to test the original validation change was broken,
most rules were unreachable and were not tested by mark_source_chains().

In some cases rulesets that used to load in a few seconds now require
several minutes.

sample ruleset that shows the behaviour:

echo "*filter"
for i in $(seq 0 100000);do
        printf ":chain_%06x - [0:0]\n" $i
done
for i in $(seq 0 100000);do
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
done
echo COMMIT

[ pipe result into iptables-restore ]

This ruleset will be about 74mbyte in size, with ~500k searches
though all 500k[1] rule entries. iptables-restore will take forever
(gave up after 10 minutes)

Instead of always searching the entire blob for a match, fill an
array with the start offsets of every single ipt_entry struct,
then do a binary search to check if the jump target is present or not.

After this change ruleset restore times get again close to what one
gets when reverting 36472341017529e (~3 seconds on my workstation).

[1] every user-defined rule gets an implicit RETURN, so we get
300k jumps + 100k userchains + 100k returns -&gt; 500k rule entries

Fixes: 36472341017529e ("netfilter: x_tables: validate targets of jumps")
Reported-by: Jeff Wu &lt;wujiafu@gmail.com&gt;
Tested-by: Jeff Wu &lt;wujiafu@gmail.com&gt;
Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>printk: do cond_resched() between lines while outputting to consoles</title>
<updated>2016-07-21T06:36:15+00:00</updated>
<author>
<name>Tejun Heo</name>
<email>tj@kernel.org</email>
</author>
<published>2016-01-16T00:58:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d47e078ecfce21eb3acae12d7c342a51e30169c8'/>
<id>d47e078ecfce21eb3acae12d7c342a51e30169c8</id>
<content type='text'>
commit 8d91f8b15361dfb438ab6eb3b319e2ded43458ff upstream.

@console_may_schedule tracks whether console_sem was acquired through
lock or trylock.  If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched().  This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.

However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines.  Also, only a few drivers call
console_conditional_schedule() to begin with.  This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.

If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.

Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Reported-by: Calvin Owens &lt;calvinowens@fb.com&gt;
Acked-by: Jan Kara &lt;jack@suse.com&gt;
Cc: Dave Jones &lt;davej@codemonkey.org.uk&gt;
Cc: Kyle McMartin &lt;kyle@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Charles (Chas) Williams &lt;ciwillia@brocade.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8d91f8b15361dfb438ab6eb3b319e2ded43458ff upstream.

@console_may_schedule tracks whether console_sem was acquired through
lock or trylock.  If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched().  This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.

However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines.  Also, only a few drivers call
console_conditional_schedule() to begin with.  This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.

If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.

Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.

Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Reported-by: Calvin Owens &lt;calvinowens@fb.com&gt;
Acked-by: Jan Kara &lt;jack@suse.com&gt;
Cc: Dave Jones &lt;davej@codemonkey.org.uk&gt;
Cc: Kyle McMartin &lt;kyle@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Charles (Chas) Williams &lt;ciwillia@brocade.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: EHCI: declare hostpc register as zero-length array</title>
<updated>2016-07-21T06:35:59+00:00</updated>
<author>
<name>Alan Stern</name>
<email>stern@rowland.harvard.edu</email>
</author>
<published>2016-06-23T18:54:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6fcbf62da1b054958dffbf039fe42c0743072ceb'/>
<id>6fcbf62da1b054958dffbf039fe42c0743072ceb</id>
<content type='text'>
commit 7e8b3dfef16375dbfeb1f36a83eb9f27117c51fd upstream.

The HOSTPC extension registers found in some EHCI implementations form
a variable-length array, with one element for each port.  Therefore
the hostpc field in struct ehci_regs should be declared as a
zero-length array, not a single-element array.

This fixes a problem reported by UBSAN.

Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Reported-by: Wilfried Klaebe &lt;linux-kernel@lebenslange-mailadresse.de&gt;
Tested-by: Wilfried Klaebe &lt;linux-kernel@lebenslange-mailadresse.de&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 7e8b3dfef16375dbfeb1f36a83eb9f27117c51fd upstream.

The HOSTPC extension registers found in some EHCI implementations form
a variable-length array, with one element for each port.  Therefore
the hostpc field in struct ehci_regs should be declared as a
zero-length array, not a single-element array.

This fixes a problem reported by UBSAN.

Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Reported-by: Wilfried Klaebe &lt;linux-kernel@lebenslange-mailadresse.de&gt;
Tested-by: Wilfried Klaebe &lt;linux-kernel@lebenslange-mailadresse.de&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

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